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Development of environmentally sustainable and economically viable technologies for plant cell wall deconstruction to fermentable sugars has been impeded due to native plant cell wall recalcitrance to thermochemical and biological based processing. Lower severity alkaline-based pretreatment processes like Ammonia Fiber Expansion (AFEX™) can overcome several limitations of traditional pretreatment approaches (e.g., acidic pretreatments) to producing cellulosic biofuels and biochemicals. Here, we give an overview of chemical reactions taking place during alkaline pretreatments including reactions between ammonia and polysaccharides/lignin (e.g., ammonolysis, hydrolysis and Maillard-type reactions). AFEX™ based pretreatments enhance enzymatic digestibility and fermentability of lignocellulosic biomass through various chemical and ultra-structural modifications within the cell wall. An improved mechanistic understanding of the AFEX™ process has led to the development of novel alkaline pretreatments that are briefly discussed in this review.

SARS-COV-2, the etiologic agent of COVID-19 is able to infect cells through its Spike protein (SPp) which must first bind to its receptor ACE2. Most currently developed vaccines target the SARS-COV-2 encoded Spike protein. Many SARS-COV-2 variants have been identified that exhibit several mutations in their Spike protein. SARS-COV-2 variant, B.1.526 was identified in New York, U.S.A. [Annavajhala, M.K. (2021) medRxiv, DOI: 10.1101/2020.02.23.21) and shown to contain the mutations, L5F, T95I, D253G, E484K, S477N, D614G and A701V. T95 and S477 of SPp are phosphorylation sites for a number of Protein kinases, including Cdk1 and GSK-3. Here, through Computerized Structure Model Analysis and Thermodynamic Calculations, it is shown that phosphorylations of T95 and S477 increases the stabilities of SARS-COV-2 encoded SPp-ACE2 and SPp-DC-SIGN complexes with very marginal effects on the binding efficiencies between the components of the complexes, and mutations T95I and S477N antagonize the effects of the phosphorylations of T95 and S477. Thus, it appears that SARS-COV-2 variant, B.1.526 has adapted to exploit the protein phosphorylation apparatus of its host cells to its advantage, and the effects of phosphorylation of of T95 and S477 are blunted through random mutation. Whether Neutralizing Antibodies that target SPp can recognize the phosphorylated forms of SPp is currently unknown.

In this paper we present an optical characterization for quantum dot intermediate band solar cells (QDIBSCs). The cells were developed by growing a stack of ten InAs/GaAs QDs layers between p and n doped GaAs conventional emitters. Electroluminescence, EL, photoreflectance, PR, and transmission electron microscopy, TEM, were applied to the samples in order to test and characterize them optically. The results, derived from the application of the different techniques, showed a good correlation. TEM images revealed a very good structural quality of the QDs, which seem to evolve in shape-strain from the bottom to the top of the stack. Corresponding to the quality observed by TEM, strong signals from EL and PR resolved unambiguously the energy band diagram of the QDIBSCs. By fitting PR data we were able to indentify the coexistence of bands and discrete energy levels coming from the IB material. The PR data evidenced also a strong electric field over the dots, attributed to the space charge region created between the p-n emitters sandwiching the IB material. From EL results, we identified the predominantly radiative nature of the IB material related energy transitions. 23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 298-301

In 1971, Garrett Hardin published an editorial entitled _Nobody Ever Dies of Overpopulation based on the cyclone that struck East Bengal and killed an estimated 500,000 people. Overcrowding forced people to live in a dangerous place like the Gangetic Delta which is barely above sea level. Now, 37 years later, a similar situation is unfolding in the Ganges River Delta in Bangladesh. This delta is also barely above sea level, and the water keeps rising due to global warming. If a large storm were to create hurricanes in this area housing and agricultural areas would be destroyed as well as power lines and water supply which would interfere with food deliveries and medical assistance. In a worst case scenario environmental refugees could reach 25 million and the death toll could be in the millions. If global climate change was one of the antecedent causes to this worst case scenario, would seal level rise and sever weather truly be the cause of deaths?

The current paradigm of global economics with exponential and continuous economic growth is unsustainable as far as Earth system ecology is concerned. To support the Earth system and boost sustainable development, a functional and operational linkage between global ecology and economics should be established – which we term ‘carbonomics’. The simple basis of ‘carbonomics’ is that the more fossil and non-fossil carbon one has as stocks, and not flows, of carbon, the richer one is. This opinion piece makes some suggestions about how we might establish such a balanced relationship. Consilience, No 17 (2017): Issue Seventeen: 2017

The United States, which has been the poster child for car culture, has been warned of the unparalleled prospect of trillion-dollar deficits for years to come. Most state governments face severe reduction in tax monies, which will mean fewer funds for road and bridge repair, as well as reductions in other services. Personal debt is very high and home values have declined sharply, reducing the _nest egg of many families for retirement. In addition, the stock market decline has had deleterious effects on retirement funds. The car culture was built on cheap fuel, financing of car purchases, and a convenient national system of mostly free roads connecting nearly all parts of the United States. Personal transportation with cars has been the norm. Petroleum prices are down dramatically at the end of 2008, but people are driving less to pay off personal debt or because they have lost their jobs. Electric cars seemed promising until problems with coal-generated electricity became more generally known. In short, the car culture has passed a tipping point and alternative public transportation is not adequate for probable future needs. One characteristic of passing a tipping point is that return to the pre-tipping point conditions is very unlikely.

Some claim that humans are too numerous to become extinct. However, passenger pigeon, once the most numerous birds on the planet, are now extinct. For years, humankind has been damaging its habitat, discharging toxic chemicals into the environment, and having harmful effects on agricultural productivity due to climate change. Humankind s extinction depends on the continuation of various human activities including economic growth, addiction to fossil fuel, over consumption, overpopulation, ocean acidification, and use of toxicants. If humankind wants to remain on this planet, it must start preparing for a vastly different environment on Earth.

The establishment of new oil palm plantations in Papua-Indonesia has greatly increased in the last years. The process of new plantation establishment involves land use change, which in many cases is directly related with the loss of primary climax forest. Papua has good climate conditions for oil palm cultivation due to high precipitation and rich in nutrients soils, as well as a large amount of available land; but its remoteness and political situation involve higher risks and costs for investors. The palm oil industry generates employment opportunities, potential for development of rural areas, as well as revenue redistribution to society in the form of taxes. On the other hand, land use change can be responsible for the loss of ecosystem services, loss of natural habitats and carbon emissions. Papua-Indonesia holds very deep and ancient tribal traditions, and its population in general opposes change. This study presents the issues related to the establishment of new oil palm plantations in Papua, Indonesia. The local and global consequences are reviewed. Factors that influence the decision-making process are identified in a strengths-weakness-opportunities-threats analysis. Proceedings of the 27th European Biomass Conference and Exhibition, 27-30 May 2019, Lisbon, Portugal, pp. 1611-1621

Scientists and inventors have proposed a variety of technologies to avoid further increases in the Earth s temperature by greenhouse gases. The two most popular technological approaches are: reflecting solar energy back into space and sequestering and storing carbon to prevent it from reentering the atmosphere. These last ditch efforts are now being referred to as _Hail Mary technologies, or efforts made in desperation with only a small chance of success. However, humankind due to the severity of the situation, has given these _Hail Mary technologies a serious consideration, even though these approaches have not be adequately researched to address one component of a much larger problem.