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1.
J Alzheimers Dis ; 98(3): 1079-1094, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38489186

RESUMO

Background: A theoretical endpoint staging framework was previously developed and published, aligning outcomes (i.e., memory) to the stage of Alzheimer's disease (AD) in which a given outcome is most relevant (i.e., has the greatest risk of degradation). The framework guides the selection of endpoints measuring outcomes relevant within a target AD population. Here, a proof of concept is presented via post-hoc analyses of the Alzheimer Management by Albumin Replacement (AMBAR) Phase 2b clinical trial in patients with AD (NCT01561053, 2012). Objective: To evaluate whether aligning endpoints measuring cognition, function, and quality of life to hypothesized 'target' stages of AD yields magnitudes of treatment efficacy greater than those reported in the AMBAR full analysis set (FAS). Methods: Three endpoints were tested: ADAS-Cog 12, ADCS-ADL, and QoL-AD. The magnitude of treatment efficacy was hypothesized to be maximized in the target stages of mild, mild-to-moderate, and very mild AD, respectively, compared to the full analysis set (FAS) and non-target stages. Results: For ADAS-Cog 12, the magnitude of treatment efficacy was largest in the non-target stage (-4.0, p = 0.0760) compared to target stage and FAS. For ADCS-ADL and QoL-AD, the magnitude of treatment efficacy was largest in the target stage (14.2, p = 0.0003; 2.4, p < 0.0001, respectively) compared to non-target stage and FAS. Conclusions: Findings indicated that evaluating endpoints in the most relevant AD stage can increase the magnitude of the observed treatment efficacy. Evidence provides preliminary proof of concept for the endpoint staging framework.


Assuntos
Doença de Alzheimer , Qualidade de Vida , Humanos , Cognição
2.
Neurol Ther ; 13(1): 69-83, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37910303

RESUMO

INTRODUCTION: Although acute and preventive treatments for migraine are commonly given in combination, data on the real-world effectiveness of ubrogepant as an acute treatment when used with an anti-calcitonin gene-related peptide (CGRP) monoclonal antibody (with or without onabotulinumtoxinA) are limited. This analysis sought to evaluate the real-world effectiveness, treatment satisfaction, and optimization of ubrogepant for the acute treatment of migraine when used in combination with an anti-CGRP monoclonal antibody, with or without concomitant onabotulinumtoxinA. METHODS: This prospective, multiple-attack, open-label, observational study (COURAGE) assessed meaningful pain relief (MPR), return to normal function (RNF), treatment satisfaction, and acute treatment optimization of ubrogepant (50 or 100 mg) when combined with an anti-CGRP monoclonal antibody, onabotulinumtoxinA, or both in adult users of Migraine Buddy, a migraine tracking application. RESULTS: In the ubrogepant and anti-CGRP monoclonal antibody arm (n = 245), following the first ubrogepant-treated attack, 61.6% (151/245) and 80.4% (197/245) of ubrogepant-treated participants achieved MPR at 2 and 4 h post-dose, respectively, and 34.7% (85/245) and 55.5% (136/245) achieved RNF at 2 and 4 h post-dose, respectively. Across up to 10 ubrogepant-treated attacks (N = 1153), MPR was achieved in 51.3% (592/1153) and 73.5% (847/1153) at 2 and 4 h post-dose, respectively. RNF was achieved by 32.2% (371/1153) and 53.2% (613/1153) at 2 and 4 h post-dose. After 30 days, 72.7% (168/231) of participants reported satisfaction (using a 7-point scale) with ubrogepant when used in combination with an anti-CGRP monoclonal antibody, and 79.7% (184/231) of participants achieved acute treatment optimization (defined as moderate-maximum treatment efficacy using the Migraine Treatment Optimization Questionnaire-4). CONCLUSION: Real-world ubrogepant use with an anti-CGRP monoclonal antibody was associated with MPR, RNF, satisfaction, and acute treatment optimization.

4.
Polymers (Basel) ; 15(21)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37959983

RESUMO

A detailed structural investigation of a promising bio-based polymer, polyglycerol citrate polyester, obtained by the bulk polycondensation of glycerol (Gly) against citric acid (Cit) under mild reaction was performed. The reaction in conditions with and without catalyst use (sulfuric acid, H2SO4) was investigated, showing evidence that it is possible to modify the polymer solubility according to the ratio and catalyst utilization. 13C and 1H NMR indicated that synthesis catalyzed with Cit excess leads to higher esterification degrees of citrate groups. In contrast, the Gly moieties are more prominent in catalyzed polymers regardless of the excess monomers. Overall, a successful conversion of Gly and Cit into polyesters was attained even without catalysis, enabling a simple route for the large-scale production of this green material to be used as a coating material. This polymer has been shown to be well-suited for coating seeds and might be a promising material for similar agricultural applications. Tests on soybean seed coating with a PGCit solution of 75% indicated that the seed quality and germination rate were not affected by the PGCit coating, concluding that this polymer is suitable for this application.

5.
J Headache Pain ; 24(1): 102, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537578

RESUMO

BACKGROUND: Individuals using onabotulinumtoxinA as a preventive migraine treatment often use acute treatments for breakthrough attacks. Data on real-world effectiveness of the small-molecule calcitonin gene-related peptide (CGRP) receptor antagonist ubrogepant in combination with onabotulinumtoxinA are limited. METHODS: COURAGE, a prospective, multiple attack, observational study, evaluated the real-world effectiveness of ubrogepant (50 or 100 mg) for acute treatment of migraine in people receiving onabotulinumtoxinA, an anti-CGRP monoclonal antibody (mAb), or both. This analysis focused only on onabotulinumtoxinA users. The Migraine Buddy app was used to identify eligible participants and track response to treated attacks. For each ubrogepant-treated attack, meaningful pain relief (MPR) and return to normal function (RNF) at 2 and 4 h post-dose over 30 days was assessed. MPR was defined as a level of relief that is meaningful to the participant, usually occurring before the pain is all gone. After 30 days, satisfaction was reported on a 7-point scale and overall acute treatment optimization was evaluated using the migraine Treatment Optimization Questionnaire-4 (mTOQ-4). RESULTS: This analysis included 122 participants who received ubrogepant and onabotulinumtoxinA and reported on 599 ubrogepant-treated attacks. Following the first ubrogepant-treated attack, MPR was achieved in 53.3% of participants 2 h post-dose and in 76.2% of participants 4 h post-dose. RNF was achieved in 25.4% of participants 2 h post-dose and in 45.9% of participants 4 h post-dose. MPR and RNF results were similar across up to 10 ubrogepant-treated attacks. After 30 days, satisfaction with ubrogepant in combination with onabotulinumtoxinA was reported by 69.8% of participants and acute treatment optimization (defined as mTOQ-4 score ≥ 4) was achieved in 77.6%. CONCLUSIONS: In this prospective real-world effectiveness study, ubrogepant treatment in onabotulinumtoxinA users with self-identified migraine was associated with high rates of MPR and RNF at 2 and 4 h as well as satisfaction and acute treatment optimization. Although the lack of a contemporaneous control group limits causal inference, these findings demonstrate the feasibility of using a novel, app-based design to evaluate the real-world effectiveness and satisfaction of treatments.


Assuntos
Toxinas Botulínicas Tipo A , Coragem , Transtornos de Enxaqueca , Humanos , Toxinas Botulínicas Tipo A/uso terapêutico , Estudos Prospectivos , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/prevenção & controle , Dor/tratamento farmacológico , Satisfação Pessoal , Resultado do Tratamento
6.
Nature ; 620(7972): 92-96, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532814

RESUMO

Cyclic nanometre-scale sandwich complexes assembled from individual building blocks were synthesized. Sandwich complexes, in which a metal ion is π-coordinated by two planar aromatic organic rings belong to the foundations of organometallic chemistry. They have been successfully used in a wide variety of applications ranging from catalysis, synthesis and electrochemistry to nanotechnology, materials science and medicine1,2. Extending the sandwich structural motif leads to linear multidecker compounds, in which aromatic organic rings and metal atoms are arranged in an alternating fashion. However, the extension to a cyclic multidecker scaffold is unprecedented. Here we show the design, synthesis and characterization of an isomorphous series of circular sandwich compounds, for which the term 'cyclocenes' is suggested. These cyclocenes consist of 18 repeating units, forming almost ideally circular, closed rings in the solid state, that can be described by the general formula [cyclo-MII(µ-η8:η8-CotTIPS)]18 (M = Sr, Sm, Eu; CotTIPS = 1,4-(iPr3Si)2C8H62-). Quantum chemical calculations lead to the conclusion that a unique interplay between the ionic metal-to-ligand bonds, the bulkiness of the ligand system and the energy gain on ring closure, which is crucially influenced by dispersion interactions, facilitate the formation of these cyclic systems. Up to now, only linear one-dimensional multidecker sandwich compounds have been investigated for possible applications such as nanowires3-10. This textbook example of cyclic sandwich compounds is expected to open the door for further innovations towards new functional organometallic materials.

7.
Front Plant Sci ; 14: 1191249, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457355

RESUMO

Due to its ample production of lignocellulosic biomass, Sida hermaphrodita (Sida), a perennial forb, is considered a valuable raw material for biorefinery processes. The recalcitrant nature of Sida lignocellulosic biomass towards pretreatment and fractionation processes has previously been studied. However, Sida is a non-domesticated species and here we aimed at expanding the potential of such plants in terms of their processability for downstream processes by making use of the natural variety of Sida. To achieve this goal, we established a collection comprising 16 different Sida accessions obtained from North America and Europe. First, we asked whether their cell wall characteristics are reflected in genetic distance or geographical distribution, respectively. A genotyping-by-sequencing (GBS) analysis resulting in a phylogenic tree based on 751 Single Nucleotide Polymorphisms (SNPs), revealed a high genetic diversity and a clear separation between accessions collected in North America and Europe. Further, all three North American accessions were separated from each other. Of the eleven European accessions, five form individual groups and six others belong to a single group. Clonal plants of seven selected accessions of American and European origin were produced and cultivated under greenhouse conditions and the resulting plant material was used for in-depth wet-chemical and spectroscopic cell wall characterization. Two accessions with contrasting cell wall characteristics were then selected and processed using the OrganoCat technology. Results of the different product yields and chemical compositions are reported. Overall, cell wall analyses revealed contrasting clusters regarding these main components between the accessions that can be related to genetic and, partly, geographical distance. Phenotypically, the accessions clustered into two groups that are not entirely overlapping with geographical origin. These results can be the basis for a targeted selection or cultivation of Sida accessions for biorefinery approaches.

8.
Front Plant Sci ; 13: 1041924, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36570952

RESUMO

Sugarcane bagasse is commonly combusted to generate energy. Unfortunately, recycling strategies rarely consider the resulting ash as a potential fertilizer. To evaluate this recycling strategy for a sustainable circular economy, we characterized bagasse ash as a fertilizer and measured the effects of co-gasification and co-combustion of bagasse with either chicken manure or sewage sludge: on the phosphorus (P) mass fraction, P-extractability, and mineral P phases. Furthermore, we investigated the ashes as fertilizer for soybeans under greenhouse conditions. All methods in combination are reliable indicators helping to assess and predict P availability from ashes to soybeans. The fertilizer efficiency of pure bagasse ash increased with the ash amount supplied to the substrate. Nevertheless, it was not as effective as fertilization with triple-superphosphate and K2SO4, which we attributed to lower P availability. Co-gasification and co-combustion increased the P mass fraction in all bagasse-based ashes, but its extractability and availability to soybeans increased only when co-processed with chicken manure, because it enabled the formation of readily available Ca-alkali phosphates. Therefore, we recommend co-combusting biomass with alkali-rich residues to increase the availability of P from the ash to plants.

9.
PLoS One ; 17(11): e0277365, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36395095

RESUMO

The knowledge of the structural and chemical properties of biochars is decisive for their application as technical products. For this reason, methods for the characterization of biochars that are generally applicable and allow quality control are highly desired. Several methods that have shown potential in other studies were used to investigate two activated carbons and seven biochars from different processes and feedstock. The chars were chosen to cover a wide range of chemical composition and structural properties as a hardness test for the analytical methods used in this study. Specific problems connected with the pretreatment of samples and drawbacks of some methods for some types of chars could be identified in an integrated consideration of the results from different methods. None of the spectroscopic methods was found to be suitable for the quality control of all types of chars. The most valuable results were obtained by chemical analysis that, however, required the complete determination of the main elements, including that of oxygen, and of inorganic components for adequate results. The combination of X-ray photoelectron spectroscopy (XPS) and FT-IR spectroscopy allows a rough characterization of surface functional groups, but cannot discriminate aliphatic and aromatic OH groups. FT-IR might be a suitable method for the quality control of biochars made at lower temperature. The results of Raman spectroscopy did not well correlate with the amount of sp2 hybridized carbon determined by XPS. A better correlation of XPS data was found with the electrical polarization determined by the method of spectral induced polarization that was used for the first time in conjunction with extensive analytical characterization.


Assuntos
Carvão Vegetal , Espectroscopia de Infravermelho com Transformada de Fourier , Carvão Vegetal/química , Espectroscopia Fotoeletrônica , Temperatura
10.
Sci Rep ; 12(1): 14176, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35986201

RESUMO

Struvite (St) recovered from wastewaters is a sustainable option for phosphorus (P) recovery and fertilization, whose solubility is low in water and high in environments characterized by a low pH, such as acidic soils. To broaden the use of struvite in the field, its application as granules is recommended, and thus the way of application should be optimized to control the solubility. In this study struvite slow-release fertilizers were designed by dispersing St particles (25, 50, and 75 wt%) in a biodegradable and hydrophilic matrix of thermoplastic starch (TPS). It was shown that, in citric acid solution (pH = 2), TPS promoted a steadier P-release from St compared to the pure St pattern. In a pH neutral sand, P-diffusion from St-TPS fertilizers was slower than from the positive control of triple superphosphate (TSP). Nevertheless, St-TPS featured comparable maize growth (i.e. plant height, leaf area, and biomass) and similar available P as TSP in sand after 42 days of cultivation. These results indicated that St-TPS slow P release could provide enough P for maize in sand, achieving a desirable agronomic efficiency while also reducing P runoff losses in highly permeable soils.


Assuntos
Fertilizantes , Areia , Fertilização , Fertilizantes/análise , Fosfatos/química , Fósforo/química , Solo/química , Estruvita/química , Zea mays
11.
Sci Total Environ ; 841: 156688, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35716738

RESUMO

Agricultural output needs significant increases to feed the growing population. Fertilizers are essential for plant production systems, with nitrogen (N) being the most limiting nutrient for plant growth. It is commonly supplied to crops as urea. Still, due to volatilization, up to 50 % of the total N application is lost. Slow or controlled release fertilizers are being developed to reduce these losses. The co-application of zinc (Zn) as a micronutrient can increase N absorption. Thus, we hypothesize that the controlled delivery of both nutrients (N and Zn) in an integrated system can improve uptake efficiency. Here we demonstrate an optimized fertilizer nanocomposite based on urea:urea-formaldehyde matrix loaded with ZnSO4 or ZnO. This nanocomposite effectively stimulates maize development, with consequent adequate N uptake, in an extreme condition - a very nutrient-poor sand substrate. Our results indicate that the Zn co-application is beneficial for plant development. However, there were advantages for ZnO due to its high Zn content. We discuss that the dispersion favors the Zn delivery as the nanoparticulated oxide in the matrix. Concerning maize development, we found that root morphology is altered in the presence of the fertilizer nanocomposite. Increased root length and surface area may improve soil nutrient uptake, potentially accompanied by increased root exudation of essential compounds for N release from the composite structure.


Assuntos
Nanocompostos , Oligoelementos , Óxido de Zinco , Fertilização , Fertilizantes/análise , Formaldeído , Micronutrientes , Nitrogênio/química , Areia , Solo/química , Ureia/química , Zea mays , Zinco/química , Óxido de Zinco/química
12.
Front Plant Sci ; 13: 861574, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35620702

RESUMO

In face of the alarming world population growth predictions and its threat to food security, the development of sustainable fertilizer alternatives is urgent. Moreover, fertilizer performance should be assessed not only in terms of yield but also in root system development, as it impacts soil fertility and crop productivity. Fertilizers containing a polysulfide matrix (PS) with dispersed struvite (St) were studied for S and P nutrition due to their controlled-release behavior. Soybean cultivation in a closed system with St/PS composites provided superior biomass compared to a reference of triple superphosphate (TSP) with ammonium sulfate (AS), with up to 3 and 10 times higher mass of shoots and roots, respectively. Root system architectural changes may explain these results, with a higher proliferation of second order lateral roots in response to struvite ongoing P delivery. The total root length was between 1,942 and 4,291 cm for plants under St/PS composites and only 982 cm with TSP/AS. While phosphorus uptake efficiency was similar in all fertilized treatments (11-14%), St/PS achieved a 22% sulfur uptake efficiency against only 8% from TSP/AS. Overall, the composites showed great potential as efficient slow-release fertilizers for enhanced soybean productivity.

13.
Chemistry ; 27(61): 15119-15126, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34427374

RESUMO

A novel bis(diphenylphosphino)methane (DPPM) functionalized amidine ligand (DPPM-C(N-Dipp)2 H) (Dipp=2,6-diisopropylphenyl) was synthesized. Subsequent deprotonation with suitable alkali metal bases resulted in the corresponding complexes [M{DPPM-C(N-Dipp)2 }(Ln )] (M=Li, Na, K, Rb, Cs; L=thf, Et2 O). The alkali metal complexes form monomeric species in the solid state, exhibiting intramolecular metal-π-interactions. In addition, a caesium derivative [Cs{PPh2 CH2 -C(N-Dipp)2 }]6 was obtained by cleavage of a diphenylphosphino moiety, forming an unusual six-membered ring structure in the solid state. All complexes were fully characterized by single crystal X-ray diffraction, NMR spectroscopy, IR spectroscopy as well as elemental analysis. Furthermore, the photoluminescent properties of the complexes were thoroughly investigated, revealing differences in emission with regards to the respective alkali metal. Interestingly, the hexanuclear [Cs{PPh2 CH2 -C(N-Dipp)2 }]6 metallocycle exhibits a blue emission in the solid state, which is significantly red-shifted at low temperatures. The bifunctional design of the ligand, featuring orthogonal donor atoms (N vs. P) and a high steric demand, is highly promising for the construction of advanced metal and main group complexes.

14.
Front Psychol ; 12: 629464, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33796047

RESUMO

There is considerable evidence that listeners' understanding of a spoken sentence need not always follow from a full analysis of the words and syntax of the utterance. Rather, listeners may instead conduct a superficial analysis, sampling some words and using presumed plausibility to arrive at an understanding of the sentence meaning. Because this latter strategy occurs more often for sentences with complex syntax that place a heavier processing burden on the listener than sentences with simpler syntax, shallow processing may represent a resource conserving strategy reflected in reduced processing effort. This factor may be even more important for older adults who as a group are known to have more limited working memory resources. In the present experiment, 40 older adults (M age = 75.5 years) and 20 younger adults (M age = 20.7) were tested for comprehension of plausible and implausible sentences with a simpler subject-relative embedded clause structure or a more complex object-relative embedded clause structure. Dilation of the pupil of the eye was recorded as an index of processing effort. Results confirmed greater comprehension accuracy for plausible than implausible sentences, and for sentences with simpler than more complex syntax, with both effects amplified for the older adults. Analysis of peak pupil dilations for implausible sentences revealed a complex three-way interaction between age, syntactic complexity, and plausibility. Results are discussed in terms of models of sentence comprehension, and pupillometry as an index of intentional task engagement.

15.
Sci Rep ; 11(1): 7621, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33828167

RESUMO

Nitrogen fertilization has been a critical factor for high crop productivity, where urea is currently the most used N source due to its high concentration and affordability. Nevertheless, urea fast solubilization leads to frequent losses and lower agronomic efficiency. The modification of urea structure by condensation with formaldehyde has been proposed to improve nutrient uptake by plants and to reduce environmental losses. Herein we show that the co-formulation with Zn strongly modifies the N release (in lab conditions) and, more important, the Zn source-ZnSO4 or ZnO-has a critical role. Urea-formaldehyde (UF) served as a matrix for the zinc sources, and chemical characterizations revealed that Zn particles influenced the length of the polymeric chain formation. Release tests in an aqueous medium showed that the UF matrix favors ZnO release and, on the other hand, delays ZnSO4 delivery. Soil incubation with the fertilizer composites proved the slow-release of N from UF, is ideal for optimizing nutritional efficiency. Our results indicated that the ZnO-UF system has beneficial effects for both nutrients, i.e., reduces N volatilization and increases Zn release.

16.
Rev Sci Instrum ; 92(2): 023506, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33648119

RESUMO

The Toroidal Magnetized System device has been significantly upgraded to enable development of various wall conditioning techniques, including methods based on ion and electron cyclotron (IC/EC) range of frequency plasmas, and to complement plasma-wall interaction research in tokamaks and stellarators. The toroidal magnetic field generated by 16 coils can reach its maximum of 125 mT on the toroidal axis. The EC system is operated at 2.45 GHz with up to 6 kW forward power. The IC system can couple up to 6 kW in the frequency range of 10 MHz-50 MHz. The direct current glow discharge system is based on a graphite anode with a maximum voltage of 1.5 kV and a current of 6 A. A load-lock system with a vertical manipulator allows exposure of material samples. A number of diagnostics have been installed: single- and triple-pin Langmuir probes for radial plasma profiles, a time-of-flight neutral particle analyzer capable of detecting neutrals in the energy range of 10 eV-1000 eV, and a quadrupole mass spectrometer and video systems for plasma imaging. The majority of systems and diagnostics are controlled by the Siemens SIMATIC S7 system, which also provides safety interlocks.

17.
Front Plant Sci ; 12: 767254, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35058946

RESUMO

Biomass from perennial plants can be considered a carbon-neutral renewable resource. The tall wheatgrass hybrid Szarvasi-1 (Agropyron elongatum, hereafter referred to as "Szarvasi") belongs to the perennial Poaceae representing a species, which can grow on marginal soils and produce large amounts of biomass. Several conventional and advanced pretreatment methods have been developed to enhance the saccharification efficiency of plant biomass. Advanced pretreatment methods, such as microwave-assisted pretreatment methods are faster and use less energy compared to conventional pretreatment methods. In this study, we investigated the potential of Szarvasi biomass as a biorefinery feedstock. For this purpose, the lignocellulosic structure of Szarvasi biomass was investigated in detail. In addition, microwave-assisted pretreatments were applied to Szarvasi biomass using different reagents including weak acids and alkali. The produced pulp, hydrolysates, and extracted lignin were quantitatively characterized. In particular, the alkali pretreatment significantly enhanced the saccharification efficiency of the pulp 16-fold compared to untreated biomass of Szarvasi. The acid pretreatment directly converted 25% of the cellulose into glucose without the need of enzymatic digestion. In addition, based on lignin compositional and lignin linkage analysis a lignin chemical model structure present in Szarvasi biomass could be established.

18.
Front Plant Sci ; 11: 572741, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329631

RESUMO

Intensive agriculture and horticulture heavily rely on the input of fertilizers to sustain food (and feed) production. However, high carbon footprint and pollution are associated with the mining processes of P and K, and the artificial nitrogen fixation for the production of synthetic fertilizers. Organic fertilizers or recovered nutrients from different waste sources can be used to reduce the environmental impact of fertilizers. We tested two recovered nutrients with slow-release patterns as promising alternatives for synthetic fertilizers: struvite and a commercially available organic fertilizer. Using these fertilizers as a nitrogen source, we conducted a rhizotron experiment to test their effect on plant performance and nutrient recovery in lupine plants. Plant performance was not affected by the fertilizer applied; however, N recovery was higher from the organic fertilizer than from struvite. As root architecture is fundamental for plant productivity, variations in root structure and length as a result of soil nutrient availability driven by plant-bacteria interactions were compared showing also no differences between fertilizers. However, fertilized plants were considerably different in the root length and morphology compared with the no fertilized plants. Since the microbial community influences plant nitrogen availability, we characterized the root-associated microbial community structure and functionality. Analyses revealed that the fertilizer applied had a significant impact on the associations and functionality of the bacteria inhabiting the growing medium used. The type of fertilizer significantly influenced the interindividual dissimilarities in the most abundant genera between treatments. This means that different plant species have a distinct effect on modulating the associated microbial community, but in the case of lupine, the fertilizer had a bigger effect than the plant itself. These novel insights on interactions between recovered fertilizers, plant, and associated microbes can contribute to developing sustainable crop production systems.

19.
Nanoscale ; 12(39): 20065-20088, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33001101

RESUMO

This review covers the compound class of one-dimensional gold strings. These compounds feature a formally infinite repetition of gold complexes as monomers/repeating units that are held together by aurophilic interactions, i.e. direct gold-gold contacts. Their molecular structures are primarily determined in the solid state using single crystal X-ray diffraction. The chemical composition of the employed gold complexes is diverse and furthermore plays a key role in terms of structure characteristics and the resulting properties. One of the most common features of gold strings is their photoluminescence upon UV excitation. The emission energy is often dependent on the distance of adjacent gold ions and the electronic structure of the whole string. In terms of gold strings, these parameters can be fine-tuned by external stimuli such as solvent, pH value, pressure or mechanical stress. This leads to direct structure-property correlations, not only with regard to the photophysical properties, but also electric conductivity for potential application in nanoelectronics. Concerning these correlations, gold strings, consisting of self-assembled individual complexes as building blocks, are the ideal compound class to look at, as perturbations by an inhomogeneity in the ligand sphere (such as the end of a molecule) can be neglected. Therefore, the aim of this review is to shed light on the past achievements and current developments in this area.

20.
Rev Sci Instrum ; 91(7): 073506, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752844

RESUMO

Equilibrium analysis in fusion devices usually relies on plasma pressure profiles and magnetic measurements outside the plasma. The kinetic profiles can give indirect information about the equilibrium magnetic field, while the stationary magnetic diagnostics cannot resolve current distributions on a smaller scale. This work presents a reciprocating magnetic probe, designed to provide direct plasma response measurements of the magnetic field in the scrape-off layer of Wendelstein 7-X. Hardware design and frequency characteristics are discussed, and a post-processing technique for extending the lower frequency cutoff of the integration scheme is presented.

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