Zinc is an essential element that facilitates coordination of immune activation during the host response to infection. We recently reported that zinc deficiency increases systemic inflammation, vital organ damage, and mortality in a small animal model of sepsis. To investigate potential mechanisms that cause these phenomena, we used the same animal model and observed that zinc deficiency increases bacterial burden and enhances NF-kappaB activity in vital organs including the lung. We conducted further studies in the lung to determine the overall impact of zinc deficiency. At the molecular level, NF-kappaB p65 DNA-binding activity was enhanced by zinc deficiency in response to polymicrobial sepsis. Furthermore, expression of the NF-kappaB-targeted genes IL-1beta, TNFalpha, ICAM-1, and the acute phase response gene SAA1/2 were elevated by zinc deficiency. Unexpectedly, the amount of NF-kappaB p65 mRNA and protein was increased in the lung including alveolar epithelia of zinc-deficient mice. These events occurred with a significant and concomitant increase in caspase-3 activity within 24 h of sepsis onset in zinc-deficient mice relative to control group. Short-term zinc supplementation reversed these effects. Reconstitution of zinc deficiency in lung epithelial cultures resulted in similar findings in response to TNFalpha. Taken together, zinc deficiency systemically enhances the spread of infection and NF-kappaB activation in vivo in response to polymicrobial sepsis, leading to enhanced inflammation, lung injury, and, as reported previously, mortality. Zinc supplementation immediately before initiation of sepsis reversed these effects thereby supporting the plausibility of future studies that explore zinc supplementation strategies to prevent sepsis-mediated morbidity and mortality.

Organic electrosynthesis can transform the chemical industry by introducing electricity-driven processes that are more energy efficient and that can be easily integrated with renewable energy sources. However, their deployment is severely hindered by the difficulties of controlling selectivity and achieving a large energy conversion efficiency at high current density due to the low solubility of organic reactants in practical electrolytes. This control can be improved by carefully balancing the mass transport processes and electrocatalytic reaction rates at the electrode diffusion layer through pulsed electrochemical methods. In this study, we explore these methods in the context of the electrosynthesis of adiponitrile (ADN), the largest organic electrochemical process in industry. Systematically exploring voltage pulses in the timescale between 5 and 150 ms led to a 20% increase in production of ADN and a 250% increase in relative selectivity with respect to the state-of-the-art constant voltage process. Moreover, combining this systematic experimental investigation with artificial intelligence (AI) tools allowed us to rapidly discover drastically improved electrosynthetic conditions, reaching improvements of 30 and 325% in ADN production rates and selectivity, respectively. This powerful AI-enhanced experimental approach represents a paradigm shift in the design of electrified chemical transformations, which can accelerate the deployment of more sustainable electrochemical manufacturing processes.

Healthcare acquired infections are a major human health problem, and are becoming increasingly troublesome with the emergence of drug resistant bacteria. Engineered surfaces that reduce the adhesion, proliferation, and spread of bacteria have promise as a mean of preventing infections and reducing the use of antibiotics. To address this need, we created a flexible plastic wrap that combines a hierarchical wrinkled structure with chemical functionalization to reduce bacterial adhesion, biofilm formation, and the transfer of bacteria through an intermediate surface. These hierarchical wraps were effective for reducing biofilm formation of World Health Organization-designated priority pathogens Gram positive methicillin-resistant Staphylococcus aureus (MRSA) and Gram negative Pseudomonas aeruginosa by 87 and 84%, respectively. In addition, these surfaces remain free of bacteria after being touched by a contaminated surface with Gram negative E. coli. We showed that these properties are the result of broad liquid repellency of the engineered surfaces and the presence of reduced anchor points for bacterial adhesion on the hierarchical structure. Such wraps are fabricated using scalable bottom-up techniques and form an effective cover on a variety of complex objects, making them superior to top-down and substrate-specific surface modification methods.

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Osteocytes are contained within spaces called lacunae and play a central role in bone remodelling. Administered frequently to prevent osteoporotic fractures, antiresorptive agents such as bisphosphonates suppress osteocyte apoptosis and may be localized within osteocyte lacunae. Bisphosphonates also reduce osteoclast viability and thereby hinder the repair of damaged tissue. Osteocyte lacunae contribute to toughening mechanisms. Following osteocyte apoptosis, the lacunar space undergoes mineralization, termed "micropetrosis". Hypermineralized lacunae are believed to increase bone fragility. Using nanoanalytical electron microscopy with complementary spectroscopic and crystallographic experiments, postapoptotic mineralization of osteocyte lacunae in bisphosphonate-exposed human bone was investigated. We report an unprecedented presence of ∼80 nm to ∼3 μm wide, distinctly faceted, magnesium whitlockite [CaMg(HPO)(PO)] crystals and consequently altered local nanomechanical properties. These findings have broad implications on the role of therapeutic agents in driving biomineralization and shed new insights into a possible relationship between bisphosphonate exposure, availability of intracellular magnesium, and pathological calcification inside lacunae.

Abstract. Forest fire is a major disturbance to the boreal ecosystem and may interact with climate change. Unfortunately, we have relatively little knowledge regarding fire activities in the boreal ecosystem. This study investigates the extent and dynamics of the forest fires occurred in and around the Boreal Ecosystem-Atmosphere Study (BOREAS) region during summer 1994, an active fire season on record. The statistics of fire activities were obtained from advanced very high resolution radiometer (AVHRR) (aboard NOAA 11) data employing two satellite-based remote sensing techniques that were designed particularly for monitoring boreal forest fires. Active fires and burned area are estimated using single-day images and 10-day clear composites. Such basic fire attributes as the area and period of burning extracted from the satellite data are compared against the ground reports made by the fire management agencies in Saskatchewan and Manitoba, Canada. Overall, there were 99 fires of a total burning area of approximately 2 million ha found over an area of 800 x 700 km 2 around the BOREAS study region in summer 1994.Agreement in the area of burning is good between the surface observations and satellitebased estimation using single-day images but poor using the composite data that suffer from various uncertainties. The majority (87%) of the ground-reported fires were detected by satellite; the satellite also identified some fires missed by the ground observers. Most fires in 1994 occurred in the transitional forest to the north and northwest of the BOREAS region. Regarding to the monitoring of fire evolution, the daily satellite detection approach can be as effective as or even more effective than ground observations, provided that cloud cover does not occur persistently. The smoke of the fires had an impact on some BOREAS flux measurements.