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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.

Observations with imaging atmospheric Cherenkov telescopes (IACTs) have enhanced our knowledge of nearby supernova (SN) remnants with ages younger than 500 yr by establishing Cassiopeia A and the remnant of Tycho’s SN as very-high-energy (VHE) γ-ray sources. The remnant of Kepler’s SN, which is the product of the most recent naked-eye SN in our Galaxy, is comparable in age to the other two, but is significantly more distant. If the γ-ray luminosities of the remnants of Tycho’s and Kepler’s SNe are similar, then the latter is expected to be one of the faintest γ-ray sources within reach of the current generation IACT arrays. Here we report evidence at a statistical level of 4.6σ for a VHE signal from the remnant of Kepler’s SN based on deep observations by the High Energy Stereoscopic System (H.E.S.S.) with an exposure of 152 h. The measured integral flux above an energy of 226 GeV is ∼0.3% of the flux of the Crab Nebula. The spectral energy distribution (SED) reveals a γ-ray emitting component connecting the VHE emission observed with H.E.S.S. to the emission observed at GeV energies with Fermi-LAT. The overall SED is similar to that of the remnant of Tycho’s SN, possibly indicating the same nonthermal emission processes acting in both these young remnants of thermonuclear SNe. Astronomy and astrophysics 662, A65 (2022). doi:10.1051/0004-6361/202243096 Published by EDP Sciences, Les Ulis

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

Contract-based nature protection schemes are a voluntary mechanism, with a limited contract duration, that aim to raise the acceptance of biodiversity conservation practices in agriculture among farmers and other land users. The purpose of this paper is to analyse the institutional settings of contract-based nature protection based on the��� ���Institutions of Sustainability��� (IoS) framework in the German Rhine-Sieg district, and to outline the way in which policy measures should be designed to encourage farmers to participate in contract-based nature protection programmes. This was achieved by answering research questions to identify the challenges, potentials and obstacles of a contract-based nature protection scheme in different ���sub-arenas��� as defined in the IoS framework. Qualitative research methods were used as the methodology. The analysis shows that main constraints for sufficient implementation of contract-based nature protection schemes are the limited consideration of the impact of climate change during the contract period, the limited consideration of regional conditions as regards the measures taken on the ground and an inflexible contract duration. International Journal on Food System Dynamics, Vol 13, No 1 (2022)

This paper examines how double exposure to both socio-economic and environmental stressors and the interaction between the two affect the population of the Northern coast of the São Paulo State, Brazil based on the conceptual and analytical framework developed by R. Leichenko and K.L. O’Brien. It provides a useful way to examine the multiple and overlapping processes of global change and, in particular, the places and the ways in which the economic and the non-economic interact. Interactions between economic and environmental change shape local landscapes of vulnerability and a major challenge for understanding vulnerability involves identifying how economic and environmental processes interact in particular places and how these interactions shape the effects of some global change processes and drive others. Pathways to increased vulnerability are multidimensional, so that socio-economic conditions may mediate the impacts of environmental change, but changing environmental conditions may also alter socio-economic capacities to maintain particular livelihood strategies. By analysing case studies of four municipalities that compound the region we found that people’s resilience, in general, are largely determined by the socio-economic context and the social vulnerability. Our finding indicate that socio-economic change brought about in the last three decades due to intense urbanization, tourism exploitation and increasingly economic activities have altered people’s livelihood and deepened social problems. We argue that the cross-scale nature of the problem and the cross-level interactions of these processes pose significant challenges for governance structures and institutions in place in the region that fail to address the roots of vulnerability and consequences of a changing environment.

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.