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The absolute dating of documents is still one of the most important challenges for forensic document examiners (FDE). The potential difference between the date on a questioned document and the actual year of production of the used paper can be only 1 to 5 years. Until now, there was no analytical method with this accuracy available. This study demonstrates a method for an absolute dating of paper by using the 14 C bomb peak and dating the starch in the paper. Accelerator mass spectroscopy (AMS) radiocarbon measurements were performed on starch extracts and cellulose fibers from 50 paper samples with known production year from 1950 to 2018. For most of the paper samples, the measured 14 C concentration values in the starch extracts were highly correlated with the data of the 14 C bomb peak calibration curve. The differences between the calibrated ages and the actual harvest years of the starch-containing plants were only up to 3 years. The 14 C concentration in the paper fibers showed a lower but significant correlation with the production year of the papers and can be used to support the dating results of the starch extracts. In order to secure the accuracy of the dating, aside from the radiocarbon measurements of the extracted starch other analytical methods or data are used, like a detailed chemical analysis of the paper composition including fiber composition and the spectroscopic analysis of the purity of the starch extracts. In practice, only starch extracts without contaminations are used for the paper dating., (© 2022 American Academy of Forensic Sciences.)

Peat-based growing media are not ecologically sustainable and peat extraction threatens sensitive peatland ecosystem. In this study, olive-stone waste (OSW) and paper waste (PW) were used in different ratios-as growing media-for ornamental crop production, as peat (P) substitutes. Marigold (Calendula officinalis L.), petunia (Petunia x hybrita L.) and matthiola (Matthiola incana L.) plants were grown in (1) P (100%), (2) P:OSW (90%:10%), (3) P:OSW (70%:30%), and (4) P:OSW:PW (60%:20%:20%). The physicochemical properties of these substrates and the effects on plant growth were determined. The addition of 10-30% OSW into the substrate increased marigold height compared to plants grown in 100% peat. No differences in plant size, plant biomass (leaves and flowers), and dry matter content were found. Adding PW, in combination with OSW, maintained marigold height and total number of flowers produced to similar levels as in plants grown in 100% peat. In matthiola, adding 30% OSW into the substrate reduced plant size and fresh weight, but not plant height. No differences were observed when plants grew in lower OSW (i.e., 10%) content. Petunia's height, its total number of flowers and flower earliness (flower opening) were increased in the presence of OSW compared to the plants grown in 100% peat. The addition of OSW did not affect petunia's size and fresh weight among treatments. The addition of PW suppressed several plant growth-related parameters for both matthiola and petunia. The insertion of OSW did not change leaf chlorophyll content whereas the presence of PW decreased chlorophylls for marigold, petunia, and matthiola. Both OSW and PW altered the content of total phenolics and antioxidant capacity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) in leaves and flowers for marigold and petunia. Both 30% OSW and PW increased antioxidative enzyme metabolism due to the increased damage index and lipid peroxidation observed in plants. Leaf N and P content decreased in PW-based media, while matthiola displayed visual phytotoxicity symptoms when PW was added into the substrate. The present work indicates that up to 30% of OSW can replace peat for marigold and petunia growing and only up to 10% of OSW for matthiola, while the addition of PW on top of OSW is not recommended, so further research is needed.

A surface-enhanced Raman scattering (SERS)-functionalized, gold nanoparticle (AuNPs)-immobilized paper strip was developed to realize label-free rapid detection of brassinosteroids (BRs) in plant tissues. The AuNPs paper strip was fabricated through utilizing poly(γ-glutamic acid) (γ-PGA) as the linker and concentrator for the directly immobilized AuNPs on paper, which can circumvent many drawbacks of the existing SERS substrates. An enhancement factor of 1.13×10 8 , high reproducibility (relative standard deviation of 4.78%), highly sensitive detection limit with a correlation coefficient of 0.99 (1×10 -11 M 4-mercaptophenylboronic acid), and long-term stability for the responses of the SERS-functionalized AuNPs paper strip to Raman intensities were achieved by optimizing reaction conditions including the concentrations of γ-PGA and HAuCl 4 /NaBH 4 . Ultimately, this developed paper strip was applied to the determination of BRs in plant tissues, obtaining precisions with RSD values in a range of 3.0-13.8%. The SERS-functionalized AuNPs paper strip featuring label-free rapid analysis, and high sensitivity could serve as an excellent alternative for on-site rapid detections., (Copyright © 2016. Published by Elsevier B.V.)

In 1910, the Russian biologist Konstantin Sergejewitch Mereschkowsky (Константин Сергеевич Мережковский, in standard transliterations also written as Konstantin Sergeevič Merežkovskij and Konstantin Sergeevich Merezhkovsky) published a notable synthesis of observations and inferences concerning the origin of life and the origin of nucleated cells. His theory was based on physiology and leaned heavily upon the premise that thermophilic autotrophs were ancient. The ancestors of plants and animals were inferred as ancestrally mesophilic anucleate heterotrophs (Monera) that became complex and diverse through endosymbiosis. He placed a phylogenetic root in the tree of life among anaerobic autotrophic bacteria that lack chlorophyll. His higher level classification of all microbes and macrobes in the living world was based upon the presence or absence of past endosymbiotic events. The paper's primary aim was to demonstrate that all life forms descend from two fundamentally distinct organismal lineages, called mykoplasma and amoeboplasma, whose very nature was so different that, in his view, they could only have arisen independently of one another and at different times during Earth history. The mykoplasma arose at a time when the young Earth was still hot, it later gave rise to cyanobacteria, which in turn gave rise to plastids. The product of the second origin of life, the amoeboplasma, arose after the Earth had cooled and autotrophs had generated substrates for heterotrophic growth. Lineage diversification of that second plasma brought forth, via serial endosymbioses, animals (one symbiosis) and then plants (two symbioses, the second being the plastid). The paper was published in German, rendering it inaccessible to many interested scholars. Here we translate the 1910 paper in full and briefly provide some context., (Copyright © 2020 The Author(s). Published by Elsevier B.V. All rights reserved.)

The use of reference solutions dispersed on filter paper discs is proposed for the first time as an external calibration strategy for matrix matching and determination of As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, V and Zn in plants by laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS). The procedure is based on the use of filter paper discs as support for aqueous reference solutions, which are further evaporated, resulting in solid standards with concentrations up to 250 μg g(-1) of each element. The use of filter paper for calibration is proposed as matrix matched standards due to the similarities of this material with botanical samples, regarding to carbon concentration and its distribution through both matrices. These characteristics allowed the use of (13)C as internal standard (IS) during the analysis by LA-ICP-MS. In this way, parameters as analyte signal normalization with (13)C, carrier gas flow rate, laser energy, spot size, and calibration range were monitored. The calibration procedure using solution deposition on filter paper discs resulted in precision improvement when (13)C was used as IS. The method precision was calculated by the analysis of a certified reference material (CRM) of botanical matrix, considering the RSD obtained for 5 line scans and was lower than 20%. Accuracy of LA-ICP-MS determinations were evaluated by analysis of four CRM pellets of botanical composition, as well as by comparison with results obtained by ICP-MS using solution nebulization after microwave assisted digestion. Plant samples of unknown elemental composition were analyzed by the proposed LA method and good agreement were obtained with results of solution analysis. Limits of detection (LOD) established for LA-ICP-MS were obtained by the ablation of 10 lines on the filter paper disc containing 40 μL of 5% HNO3 (v v(-1)) as calibration blank. Values ranged from 0.05 to 0.81  μg g(-1). Overall, the use of filter paper as support for dried aqueous standards showed to be a useful strategy for calibration and plant analysis by LA-ICP-MS., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Non-wood is one of the most important raw materials for pulp and paper production in several countries due to its abundance and cost-effectiveness. However, the pulping and papermaking characteristics of canola straw have rarely been investigated. The objective of this work was to determine the potential application of canola straw in the chemimechanical pulping (CMP) process. At first, the chemical composition and characteristics of canola straw were assessed and compared with those of other non-woods. Then, the CMP pulping of canola straw was conducted using different dosages of sodium sulfite and sodium hydroxide. The results showed that, by applying a mild chemical pretreatment, i.e., 4-12% (wt.) NaOH and 8-12% (wt.) Na(2)SO(3), in the CMP pulping of canola straw, the pulp brightness reached almost 40%ISO, and the strength properties were comparable to those of bagasse CMP and of wheat straw CMP. The impact of post-refining on the properties of canola straw CMP was also discussed in this work., (Copyright 2010 Elsevier Ltd. All rights reserved.)

In order to assess the potential of wetland plants to remediate metals from a paper mill effluent contaminated wetland site in Northeast India, 25 abundant plant species belonging to 15 different families, soil, and water samples from the sites were tested for Pb, Zn, Mg, and Fe by atomic absorption spectrophotometer. The results showed that metal accumulation by wetland plants differed among species and tissues. Plants thrived in high Pb, Zn, Mg, and Fe which indicated their tolerance. According to the criteria used for selecting plants for phytoremediation such as high metal tolerance, short life cycle, wide distribution, large shoot biomass and translocation factor (TF) >1; five species each were Mg and Fe accumulators, nine species were Pb accumulators and, eight species were Zn accumulators and the rest were excluders. Alternanthera sessilis was the only plant species that had TF > 1 for all the four metals. The study indicated great promise for phytoremediation, as these accumulators could be used in future for practical phytoremediation approaches and reduction of the risk from harmful metals to human health.

Pulping of blue agave waste, from the production of tequila, was evaluated by both chemical and biomechanical pulping processes. Two conventional and two organosolv systems were used to pulp the agave waste under a standard set of conditions. The soda-ethanol process was superior in terms of delignification and pulp properties in comparison to the soda and ethanol organosolv processes for pulping of agave waste; however, the kraft process gave the best strength properties. In general, the strength of the agave waste pulps was rather poor in comparison to wood and other agro-based pulps; however, the tear strength was relatively high. This result is typical of poorly bonded sheets and may be due to the coarseness of the agave fibers and/or loss of hemicelluloses in the steaming process for the tequila production. Fungal treatment of the agave waste with Ceriporiopsis subvermispora reduced the energy consumption for mechanical refining but gave biomechanical pulps with inferior strength properties. The blue agave chemical pulps should be suitable for blending with softwood kraft pulps for publication grade paper.

Within communities, species are wrapped in a set of feedbacks with each other and with their environment. When such feedbacks are strong enough they can generate alternative stable states. So far, research on alternative stable states has mostly focused on systems with a small number of species and a limited diversity of interaction types. Here, we analyze a spatial model of plant community dynamics in stressed ecosystems such as drylands, where each species is characterized by a strategy, and the different species interact through facilitation and competition for space and resources, such as water. We identify three different types of multistability emerging from the interplay of competition and facilitation. Under low-stress levels, plant communities organize in small groups of coexisting species, maintained by space, competition and facilitation ("cliques"). Under higher stress levels, positive feedback from facilitation lead to the dominance of a single facilitating species ("mutual exclusion states"). At the highest stress levels, the single facilitating species left in the system coexists with the desert state. By linking community ecology and alternative stable states theory using a spatial plant community model for stressed ecosystems, our study contributes to highlight the importance of positive feedback loops for the stability of ecological communities., (© 2024 The Author(s). Ecology published by Wiley Periodicals LLC on behalf of The Ecological Society of America.)

HVPE is an excellent and often overlooked method for obtaining objective and meaningful information about cell-wall "building blocks" and their metabolic precursors. It provides not only a means of analysis of known compounds but also an insight into the charge and/or mass of any unfamiliar compounds that may be encountered. It can be used preparatively or analytically. It can achieve either "class separations" (e.g. delivering all hexose monophosphates into a single pool) or the resolution of different compounds within a given class (e.g. ADP-Glc from UDP-Glc; or GlcA from GalA). All information from HVPE about charge and mass can be obtained on minute traces of analytes, especially those that have been radiolabelled, e.g. by in-vivo feeding of a (3)H- or (14)C-labelled precursor. HVPE does not usually damage the substance under investigation (unless staining is used), so samples of interest can be eluted intact from the paper ready for further analysis. Although HVPE is a technique that has been available for several decades, recently it has tended to be sidelined, possibly because the apparatus is not widely available. Interested scientists are invited to contact the author about the possibility of accessing the Edinburgh apparatus.

Rare earth elements (REEs) are widely distributed in low concentrations in all parts of the biosphere. REEs are not at all rare, their concentration in the earth’s crust is close to 0.015%. REEs include the elements scandium, yttrium and the lanthanides from lanthanum to lutetium. REEs show similar physical and chemical properties. Today REEs are applied in industries and technologies, in agriculture as microfertilizers and feed additives and they are also used in medicine. REEs are dispersed especially as accessory minerals in pegmatites, granites and associated metamorphic volcanic rocks. Out of more than 250 kinds of minerals containing REEs, only bastnaesite and monazite are of economic importance. Their concentration in the soil varies widely and depends on their presence in parental materials, soil texture, organic matter content, pedogenetic processes and anthropogenic activities. REEs are found in small concentrations in surface stagnant and flowing waters as well as in underground waters. They are found in water in both suspended and dissolved form. REEs enter the atmosphere from various sources, largely owing to human activities. The majority of REEs in the atmosphere are carried by microscopic particles. The uptake and consequently accumulation of REEs in plants are affected by numerous biotic factors, such as plant species and genotype, and abiotic factors such as their concentration in the soil and some chemical and physical soil characteristics. They can enter plants via both root and foliage tissues. There are plant species called hyperaccumulators that are able to accumulate significant amounts of REEs without adverse consequences. RREs are not biogenic for higher plants or for other living organisms, but can influence their life processes. Experi­ments show that REEs can be beneficial for growth, yield and biochemical composition of cultivated plants. They can also alleviate some ecological stress in plants. It is not clear enough how they affect human and animal health. The wide-spread application of REEs in different industries as well as in agriculture lead to a constant increase of the concentrations of these elements in the environment. Therefore, studies on the uptake, accumulation, dis­tribution of REEs in cultivated plant species and their entrance into the food chain as well as their stimulating or toxic effect on living organisms, can be very significant in the future.

The colorimetric determination of the concentration of phytochemicals in plant extract samples using a spotting automatic system, mobile phone camera and a computer with developed software for quantification is described. Method automation was achieved by using a robotic system for spotting. The instrument was set to disperse the appropriate aliquots of the reagents and sample on a Whatman paper sheet. Spots were photographed and analysed by ImageJ software or by applying the developed MatLab based algorithm. The developed assay was found to be effective, with a linear response at the concentration range of 0.03-0.25g/L for polyphenols. The detection limit of the proposed method is sub 0.03g/L. The paper microzone-based assays for flavonoids and amino acids/peptides were also developed and evaluated as applicable. Comparing the results with conventional PμZP methods demonstrates that both methods yield similar results. At the same time, the proposed method has an attractive advantage in analysis time and repeatability/reproducibility., (Copyright © 2013 Elsevier Ltd. All rights reserved.)