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Water transfer in wood plays a major role during the life time of timber structures but the physics of the various processes involved, such as wetting and imbibition, is not fully understood. Here we show that the angle of contact of a water drop placed in contact with an air dry wood surface is initially larger than 90°, then the drop slowly spreads over the surface, while the apparent (macroscopic) contact angle decreases down to a few tens of degrees. We show that similar results are obtained with a model material, i.e. hydrogel, as soon as a perturbation is induced onto the line of contact. We demonstrate that for the gel the initial large apparent contact angle results from a strong deformation of the gel in a thin softened region below the line of contact resulting from the fast diffusion of water and swelling of this region. This phenomenon ensures a real (local) contact angle close to zero. The spreading then results from the progressive diffusion of water at farther distance and successive perturbations of the line of contact when the drop enters in contact with small liquid droplets dispersed along the surface (residues of the chemical reaction during gel preparation). It is suggested that a similar effect occurs for the water drop over a wood surface and explains the large initial contact angle and slow spreading: the line of contact is initially pinned thanks to a wood surface deformation resulting from the wood surface swelling due to water absorption, thus leading to a large contact angle; it will then unpin when the local conditions have changed as a result of water diffusion at further distance, allowing for a small displacement up to the next pinning point and so on.

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Europe's roadmap to a low-carbon economy aims to cut greenhouse gas (GHG) emissions 80% below 1990 levels by 2050. Beef production is an important source of GHG emissions and is expected to increase as the world population grows. LIFE BEEF CARBON is a voluntary European initiative that aims to reduce GHG emissions per unit of beef (carbon footprint) by 15% over a 10-year period on 2172 farms in four large beef-producing countries. Changes in farms beef carbon footprint are normally estimated via simulation modelling, but the methods current models apply differ. Thus, our initial goal was to develop a common modelling framework to estimate beef farms carbon footprint. The framework was developed for a diverse set of Western Europe farms located in Ireland, Spain, Italy and France. Whole farm and life cycle assessment (LCA) models were selected to quantify emissions for the different production contexts and harmonized. Carbon Audit was chosen for Ireland, Bovid-CO2 for Spain and CAP'2ER for France and Italy. All models were tested using 20 case study farms, that is, 5 per country and quantified GHG emissions associated with on-farm live weight gain. The comparison showed the ranking of beef systems gross carbon footprint was consistent across the three models. Suckler to weaning or store systems generally had the highest carbon footprint followed by suckler to beef systems and fattening beef systems. When applied to the same farm, Carbon Audit's footprint estimates were slightly lower than CAP'2ER, but marginally higher than Bovid-CO2. These differences occurred because the models were adapted to a specific region's production circumstances, which meant their emission factors for key sources; that is, methane from enteric fermentation and GHG emissions from concentrates were less accurate when used outside their target region. Thus, for the common modelling framework, region-specific LCA models were chosen to estimate beef carbon footprints instead of a single generic model. Additionally, the Carbon Audit and Bovid-CO2 models were updated to include carbon removal by soil and other environmental metrics included in CAP'2ER, for example, acidification. This allows all models to assess the effect carbon mitigation strategies have on other potential pollutants. Several options were identified to reduce beef farms carbon footprint, for example, improving genetic merit. These options were assessed for beef systems, and a mitigation plan was created by each nation. The cumulative mitigation effect of the LIFE BEEF CARBON plan was estimated to exceed the projects reduction target (-15%).

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Four breeding piggeries and eight growing-fattening piggeries were analyzed to estimate potential environmental impacts of heavy pig production (>160kg of live height at slaughtering). Life Cycle Assessment methodology was adopted in the study, considering a system from breeding phase to growing fattening phase. Environmental impacts of breeding phase and growing-fattening phase were accounted separately and then combined to obtain the impacts of heavy pig production. The functional unit was 1kg of live weight gain. Impact categories investigated were global warming (GW), acidification (AC), eutrophication (EU), abiotic depletion (AD), and photochemical ozone formation (PO). The total environmental impact of 1kg of live weight gain was 3.3kg CO2eq, 4.9E-2kg SO2eq, 3.1E-2kg PO4(3-)eq, 3.7E-3kg Sbeq, 1.7E-3kg C2H4eq for GW, AC, EU, AD, and PO respectively. Feed production was the main hotspot in all impact categories. Greenhouse gases responsible for GW were mainly CH4, N2O, and CO2. Ammonia was the most important source of AC, sharing about 90%. Nitrate and NH3 were the main emissions responsible for EU, whereas P and NOx showed minor contributions. Crude oil and natural gas consumption was the main source of AD. A large spectrum of pollutants had a significant impact on PO: they comprised CH4 from manure fermentation, CO2 caused by fossil fuel combustion in agricultural operations and industrial processes, ethane and propene emitted during oil extraction and refining, and hexane used in soybean oil extraction. The farm characteristics that best explained the results were fundamentally connected with performance indicators Farms showed a wide variability of results, meaning that there was wide margin for improving the environmental performance of either breeding or growing-fattening farms. The effectiveness of some mitigation measures was evaluated and the results that could be obtained by their introduction have been presented.

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Available water filtration systems containing metallic iron (Fe(0) filters) are pragmatically designed. There is a lack of sound design criteria to exploit the full potential of Fe(0) filters. A science-based design relies on valuable information on processes within a Fe(0) filter, including chemical reactions, hydrodynamics and their relation to the performance of the filter. The aim of this study was to establish a simple method to evaluate the initial performance of Fe(0) filters. The differential adsorptive affinity of methylene blue (MB) onto sand and iron oxide is exploited to characterize the evolution of a Fe(0)/sand system using the pure sand system as operational reference. Five systems were investigated for more than 70 days: pure sand, pure Fe(0), Fe(0)/sand, Fe(0)/pumice and Fe(0)/sand/pumice. Individual systems were characterized by the extent of changes in pH value, iron breakthrough, MB breakthrough and hydraulic conductivity. Results showed that for MB discoloration (i) pure sand was the most efficient system, (ii) hybrid systems were more sustainable than the pure Fe(0) system, and (iii) the pores of used pumice are poorly interconnected. Characterizing the initial reactivity of Fe(0) filters using MB discoloration has introduced a powerful tool for the exploration of various aspects of filter design.

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This study quantifies the environmental impact of milk production of Italian Mediterranean buffaloes and points out the farm characteristics that mainly affect their environmental performance. Life cycle assessment was applied in a sample of 6 farms. The functional unit was 1 kg of normalized buffalo milk (LBN), with a reference milk fat and protein content of 8.3 and 4.73%, respectively. The system boundaries included the agricultural phase of the buffalo milk chain from cradle to farm gate. An economic criterion was adopted to allocate the impacts on milk production. Impact categories investigated were global warming (GW), abiotic depletion (AD), photochemical ozone formation (PO), acidification (AC), and eutrophication (EU). The contribution to the total results of the following farm activities were investigated: (1) on-farm energy consumption, (2) manure management, (3) manure application, (4) on-farm feed production (comprising production and application of chemical fertilizers and pesticides), (5) purchased feed production, (6) enteric fermentation, and (7) transport of purchased feeds, chemical fertilizers, and pesticides from producers to farms. Global warming associated with 1 kg of LBN resulted in 5.07 kg of CO2 Eq [coefficient of variation (CV)=21.9%], AD was 3.5 × 10(-3) kg of Sb Eq (CV=51.7%), PO was 6.8 × 10(-4) kg of C2H4 Eq (CV=28.8%), AC was 6.5 × 10(-2) kg of SO2 Eq (CV=30.3%), and EU was 3.3 × 10(-2) kg of PO4(3-) Eq (CV=36.5%). The contribution of enteric fermentation and manure application to GW is 37 and 20%, respectively; on-farm consumption, on-farm feed production, and purchased feed production are the main contributors to AD; about 70% of PO is due to enteric fermentation; manure management and manure application are responsible for 55 and 25% of AC and 25 and 55% of EU, respectively. Methane and N2O are responsible for 44 and 43% of GW, respectively. Crude oil consumption is responsible for about 72% of AD; contribution of CH4 to PO is 77%; NH3 is the main contributor to AC (92%); NO3(-) and NH3 are responsible for 55 and 41% of EU, respectively; contribution of P to EU is only 3.2%. The main characteristics explaining the significant variability of life cycle assessment are milk productivity and amount of purchased feed per kilogram of LBN. Improvement of LBN production per buffalo cow is the main strategy for reducing GW and PO; improvement of the efficiency of feed use is the strategy proposed for mitigating AD, PO, AC, and EU.

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Despite the amount of data available on investigating the process of aqueous contaminant removal by metallic iron (Fe(0)), there is still a significant amount of uncertainty surrounding the design of Fe(0) beds for laboratory testing to determine the suitability of Fe(0) materials for field applications. Available data were obtained under various operating conditions (e.g., column characteristics, Fe(0) characteristics, contaminant characteristics, oxygen availability, solution pH) and are hardly comparable to each other. The volumetric expansive nature of iron corrosion has been univocally reported as major drawback for Fe(0) beds. Mixing Fe(0) with inert materials has been discussed as an efficient tool to improve sustainability of Fe(0) beds. This paper discusses some problems associated with the design of Fe(0) beds and proposes a general approach for the characterization of Fe(0) beds. Each Fe(0) column should be characterized by its initial porosity, the composition of the steady phase and the volumetric proportion of individual materials. Used materials should be characterized by their density, porosity, and particle size. This work has introduced simple and reliable mathematical equations for column design, which include the normalisation of raw experimental data prior to any data treatment.

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This communication challenges the concept that nanoscale metallic iron (nano-Fe(0)) is a strong reducing agents for contaminant reductive transformation. It is shown that the inherent relationship between contaminant removal and Fe(0) oxidative dissolution which is conventionally attributed to contaminant reduction by nano-Fe(0) (direct reduction) could equally be attributed to contaminant removal by adsorption and co-precipitation. For reducible contaminants, indirect reduction by adsorbed Fe(II) or adsorbed H produced by corroding iron (indirect reduction) is even a more probable reaction path. As a result, the contaminant removal efficiency is strongly dependent on the extent of iron corrosion which is larger for nano-Fe(0) than for micro-Fe(0) in the short term. However, because of the increased reactivity, nano-Fe(0) will deplete in the short term. No more source of reducing agents (Fe(II), H and H(2)) will be available in the system. Therefore, the efficiency of nano-Fe(0) as a reducing agent for environmental remediation is yet to be demonstrated.

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Recombinant protein translation in Escherichia coli may be limited by stable (i.e. low free energy) secondary structures in the mRNA translation initiation region. To circumvent this issue, we have set-up a computer tool called 'ExEnSo' (Expression Enhancer Software) that generates a random library of 8192 sequences, calculates the free energy of secondary structures of each sequence in the -70/+96 region (base 1 is the translation initiation codon), and then selects the sequence having the highest free energy. The software uses this 'optimized' sequence to create a 5' primer that can be used in PCR experiments to amplify the coding sequence of interest prior to sub-cloning into a prokaryotic expression vector. In this article, we report how ExEnSo was set-up and the results obtained with nine coding sequences with low expression levels in E. coli. The free energy of the -70/+96 region of all these coding sequences was increased compared to the non-optimized sequences. Moreover, the protein expression of eight out of nine of these coding sequences was increased in E. coli, indicating a good correlation between in silico and in vivo results. ExEnSo is available as a free online tool.

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Histoplasmosis of the extremities is rare. A case of recurrent histoplasmosis with a 10-year latency between initial presentation and clinical recurrence is reported. Prolonged antibiotic treatment and debridement of bony involvement led to clinical resolution of this fungal infection after a follow-up period of 20 months.

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A common side effect of radiotherapy is the development of fibrosis in the irradiated tissue. To study the mechanisms of this fibrogenic response, we developed a model system of whole-lung radiation in the rat and studied the evolution of injury by assessment of the cells and protein recovered by lavage. Once the pattern of injury was known, we attempted to modulate this reaction by administering the cytokine interferon-gamma (IFN-gamma). Rats received 15 Gy radiation to the whole thorax and were studied by lung lavage at intervals of 1 to 35 days after radiation. The effect of radiation was an initial (24 h) leak of protein, unaccompanied by cellular alterations, that resolved by 48 h. This was followed 2 wk later by a phase of inflammatory cell recruitment and more significant protein leak. A third phase of increase in inflammatory cells and further increase in protein flux was noted at Day 35. A significant cellular infiltrate was seen in lung sections obtained from animals treated in parallel experiments. IFN-gamma was given by osmotic pump from Day 0 to Day 35. This treatment significantly attenuated the PMN recruitment and protein leak (p < 0.002 and 0.01, respectively) at Days 25 and 35. Histologic sections demonstrated reduced alveolar cellularity and exudate at Day 25 (p < 0.05); however, significant numbers of inflammatory cells and exudate were present in irradiated and IFN-gamma-treated animals at Day 35. These data indicate that inflammatory cell recruitment may play a role in the lung injury following radiation. Furthermore, these preliminary data indicate that a cytokine blocks this reaction.

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Human alveolar macrophages release in vitro a factor that inhibits both random migration and chemotaxis of human polymorphonuclear neutrophils (PMN). This factor is not cytotoxic and is recovered in culture supernatants of alveolar cells from most nonsmoking normal subjects. The inhibitor can be detected 30 min after cell cultures are established and is still produced after 24 h in culture. Its release was inhibited by cycloheximide. When supernatants are separated by molecular sieving (I-60 Waters HPLC column), most of the inhibitory activity is recovered in the low-molecular-weight fractions of the chromatogram (less than 1,000 D). The inhibitor has a broad spectrum of activity against known chemoattractants in that it reduces significantly the chemotaxis of PMN induced by the formyl peptide FMLP, by the complement fragment C5a, and by leukotriene B4; it also decreases the chemotactic activity associated with a monocyte-derived interleukin 1 preparation and the chemotactic activity derived from alveolar macrophage culture supernatants. The inhibitory factor is partially heat labile, is sensitive to aminopeptidase M, and is nonpolar. Both phorbol myristate acetate (PMA) and FMLP-induced superoxide release by PMN are diminished significantly in the presence of this inhibitory factor (p less than 0.01 for PMA and p less than 0.05 for FMLP). The inhibitor also reduces monocyte chemotaxis but has no effect on monocyte random migration. Finally, studies with [3H]FMLP indicate that this inhibitor does not act at the site of receptor binding on PMN. Thus, human alveolar macrophages can release in vitro both neutrophil chemotactic factors and an apparent neutrophil-inhibiting factor that may modulate positively and negatively the movement and the respiratory burst of neutrophils in the alveolar space.

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Activated macrophages can secrete a number of mediators that can attract inflammatory cells and enhance secretion of phlogistic substances from these cells. The ultimate effect of activated bronchoalveolar lavage (BAL) cells may be fibrotic lung injury. Inasmuch as pulmonary sarcoidosis is a disease associated with spontaneous activation of macrophages and lymphocytes among BAL cells, cells obtained from patients with sarcoidosis were compared with normal cells. We report that adherent BAL cells in culture from patients with sarcoidosis (n = 21) release during a resting period in vitro more chemotactic activity for neutrophils (PMNs) than do BAL cells from normal individuals (n = 14). After density fractionation of the respiratory cells by albumin gradient, cells from high-density fractions in the group with sarcoidosis secrete more chemotactic activity for neutrophils than cells from less dense fractions. The PMN chemotactic activity spontaneously released in vitro by BAL cells from patients with sarcoidosis correlates with the percentage of PMNs recovered by BAL. Immunochemical bioassay and high-performance liquid chromatographic (HPLC) analysis of BAL cell supernatants revealed a complex pattern of chemotactic factors to be present. Generally, three peaks of chemotactic activity were noted on HPLC 1-60 separations at greater than 20 kd, 8 to 10 kd, and less than 1 kd apparent molecular weights. Significantly, interleukin-1 was present in these supernatants, whereas complement components and leukotriene B4 were absent. Sarcoid BAL cells, principally alveolar macrophages, are activated in vivo as manifested by spontaneous secretion of chemotactic factors for PMNs in vitro. Interleukin-1 and other less well characterized molecules were detected. The presence of PMNs among the lavage cells of some patients with sarcoidosis appears to be an in vivo biologic correlate of this activation. These data provide additional criteria of BAL cell activation in patients with pulmonary sarcoidosis and provide further evidence concerning factors that attract inflammatory cells into the lung.

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