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Calcium (Ca) is a critical plant nutrient typically applied at the time of planting in intensive Eucalyptus plantations in South America. At two sites in Colombia, we examined (1) calcium source by comparing growth after application of 100 kg ha−1 elemental Ca as lime or as pelletized highly reactive calcium fertilizer (HRCF) compared to a no application control, and (2) Ca rate by applying 0, 100, 200, and 400 kg ha−1 elemental Ca as HRCF with the addition of nitrogen, phosphorus, potassium, sulfur, and boron (NPKSB). We assessed height, diameter, and volume after 12 and 24 months. There were no growth differences from Ca source at the 100 kg ha−1 rate. We found increased volume after 24 months at the “Popayan” site with 200 and 400 kg ha−1 Ca HRCF+NPKSB treatments (112 and 113 m3 ha−1, respectively) compared to control (92 m3 ha−1), a 22% increase. In contrast, volume did not differ after 24 months at the “Darien” site, ranging from 114 m3 ha−1 in the 0 kg ha−1 Ca HRCF+NPKSB treatment to 98 m3 ha−1 in the control. Differences in response are likely due to soil characteristics, such as organic matter, emphasizing the importance of identifying site-specific nutrient deficiencies.

The addition of inorganic filler material in medium density fiberboard (MDF) and the effect on material properties as a function of particle size was examined. Medium density fiberboard was manufactured in a laboratory scale environment to a target raw densityof 750 kgm-3. Wood fibers were replaced by using calcium carbonate at 3 and 10 wt.% using fillers with weighted median particle sizes of d50= 2.0 μm and d50= 30 μm, respectively. Urea formaldehyde resin was used as binder in all MDF. The influence of filler addition on the modulus of elasticity, bending and tensile strength, dimensional stability and liquid permeability was investigated. The results demonstrate the effect of filler content and its dependence on particle size. The addition of filler with d50= 30 μm does not have any influence on material properties up to a filler content of 10 wt.%. Using the finer filler with d50= 2.0 μm at 10 wt.% filler, the quantity significantly increases the water adsorption and swelling behavior and reduces the strength properties of the MDF.

Addition of mineral filler in the surface layer of three-layer particle board and its influence on material properties was studied as a function of filler content. Three-layer particle board with a...

The unprecedented coronavirus disease 2019 (COVID-19) pandemic is a solemn reminder of the need to accelerate pharmaceutical innovation. The desire for fast access to vaccines triggered discussion of unrestricted access to research findings with the hope of facilitating the drug discovery process to combat COVID-19. Increasingly, abolition of the patent system is being discussed in connection with the fight against the pandemic. This may accelerate discovery of and increase access to medicines. However, society's desire for immediate disclosure of research findings conflicts with the inventor's legitimate interest to protect his or her invention as well as the need to recover investments made to develop the drug. The call for immediate disclosure of research results contradicts the interest of the inventor, whose primary goal is to secure his intellectual property rights, usually by applying for patent protection. In Europe, where patent law is based on the principle of absolute novelty, disclosure of the results reduces novelty and prevents subsequent patenting. Consequently, patenting remains the top priority for pharmaceutical companies in Europe, while disclosure of the results is secondary. The following article looks critically at the idea of using the grace period in European patent law to reconcile the conflicting interests of society and inventors in times of pandemic. In this paper, we investigate whether the implementation of a grace period in European patent law like that known in the USA, Japan, or Korea benefits the disclosure of results and increases the flow of information, ultimately leading to the promotion of innovation and rapid drug discovery. This article questions whether the use of a grace period provides a sufficient incentive to the inventor for rapid disclosure.

Calcium hydrogen phosphate dihydrate (DCPD) was evaluated for its potential as a mineral fire retardant (FR) for application in melamine-urea-formaldehyde (MUF)-bonded wood composites. The efficacy as FR was studied in melamine-urea-formaldehyde (MUF)-bonded three-layer particleboard as a function of addition quantities of 10-, 20- and 30¿wt%. Resistance to fire and mechanical properties were determined by measuring the self-extinguishing time after flame exposure and internal bond strength, respectively. Combustion behavior was examined on samples with 20¿wt% DCPD addition by performing cone calorimetry experiments. The efficacy of DCPD was evaluated by determining the heat release, total heat release rate, smoke production, and smoke production rate and compared to another promising mineral-based fire-retardant composition (FRC) based on hydroxyapatite (HA) with deliquescent salt and HA alone. The effect of FR on the curing behavior of MUF in relation to mechanical properties was determined through viscosity measurements of MUF with 10 wt% addition of FR. The results confirmed the fire-retardant characteristics of DCPD in wood composites, albeit at higher application rates when compared to the FRC, however with no negative impact on resin curing time or mechanical strength. Based on the demonstrated compatibility in MUF, DCPD is considered a promising mineral extender of other FRs for application in UF-based wood composites.

The influence of inorganic mineral filler addition on the material properties of medium density fiberboard (MDF) was inves- tigated at varying densities. Fibreboards with 10, 20 and 30% fibers replaced by calcium carbonate weight basis (dry/dry) and with target densities of 550, 700 and 850 kgm−3, respectively, were manufactured in a laboratory scale environment. The fiberboards were prepared by adding the mineral filler in dry powder form to the wood fibers to which urea formaldehyde UF resin in liquid state had previously been added. The obtained fiber-filler furnish, with the filler distributed uniformly by sticking to the UF resin on the fibers, was then pressed into panel forms. The effect of inorganic filler on elastic and strength properties, thickness swelling, permeability, as well as formaldehyde and volatile organic compound (VOC) emissions was quantified. The results demonstrate that the addition of mineral filler to MDF up to levels of 10 wt.% only have a small effect, if at all, on the material properties. The addition of calcium carbonate, and the associated increase in pH, does not have any effect on the strength development in the cured MDF, even though the results clearly demonstrate the negative effect on the curing kinetics of urea formaldehyde (UF) resin. Likewise, thickness swelling and formaldehyde and volatile organic com- pounds (VOC’s) emissions are not affected by filler addition levels of up to 10 wt.%. However, exceeding this level leads to a significant decline in strength, which is believed to be caused mainly by a reduction in the number of fiber-to-fiber stress transfer points. Further, increased emissions in VOC’s are expected due to a combination of the catalytic effect of the calcium carbonate that causes a breakdown of fatty acids to VOC’s and also increased emission rates due to a higher permeability of the MDF with filler addition levels above 10 wt.%.

The cultivation of Populus spp. on acid soils is difficult mainly due to low nutrient availability, limiting the distribution and use of this marketable tree species. In this paper we report the results of two experiments, in which a granulated highly reactive micronized calcium carbonate (CaCO) was tested at increasing levels to improve the effect of NPKS fertilization on poplar growth. Twin field and pot experiments were carried out in 2017 using two different poplar clones, both of which are often used in Italy. In addition to analysing the data from the two experiments separately, common patterns were evaluated using a mixed-effect model with CaCO level and fertilization as fixed effects, and the experiment type as random effect. Growth was assessed in terms of total height, diameter and biomass. Taken together, the results from the two experiments showed that fertilization led to enhanced growth of poplar, but this effect was stronger when soil conditions in terms of pH and exchangeable Ca were at a sufficiently high level. Available nutrient concentrations in the soil and foliar nutrient concentrations in the plant suggested co-limitation of poplar growth by N and Ca. In conclusion, the results of this study on one hand emphasize the importance of adapting the level of CaCO to the given soil conditions, and on the other hand ask for further studies addressing the relative importance of elevated pH and improved Ca nutrition.