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Carbon stored in harvested wood products (HWPs) can affect national greenhouse gas (GHG) inventories, in which the production and end use of HWPs play a key role. The Intergovernmental Panel on Climate Change (IPCC) provides guidance on HWP carbon accounting, which is sensitive to future developments of socioeconomic factors including population, income, and trade. We estimated the carbon stored within HWPs from 1961 to 2065 for 180 countries following IPCC carbon-accounting guidelines, consistent with Food and Agriculture Organization of the United Nations (FAOSTAT) historical data and plausible futures outlined by the shared socioeconomic pathways. We found that the global HWP pool was a net annual sink of 335 Mt of CO₂ equivalent (CO₂e)·y−1 in 2015, offsetting substantial amounts of industrial processes within some countries, and as much as 441 Mt of CO₂e·y−1 by 2030 under certain socioeconomic developments. Furthermore, there is a considerable sequestration gap (71 Mt of CO₂e·y−1 of unaccounted carbon storage in 2015 and 120 Mt of CO₂e·y−1 by 2065) under current IPCC Good Practice Guidance, as traded feedstock is ineligible for national GHG inventories. However, even under favorable socioeconomic conditions, and when accounting for the sequestration gap, carbon stored annually in HWPs is <1% of global emissions. Furthermore, economic shocks can turn the HWP pool into a carbon source either long-term—e.g., the collapse of the USSR—or short-term—e.g., the US economic recession of 2008/09. In conclusion, carbon stored within end-use HWPs varies widely across countries and depends on evolving market forces.

This study evaluated the effects on forest resources and forest product markets of three contrasting mass timber demand scenarios (Conservative, Optimistic, and Extreme), up to 2060, in twelve selected countries in Asia, Europe, North America, and South America. Analyses were carried out by utilizing the FOrest Resource Outlook Model, a partial market equilibrium model of the global forest sector. The findings suggest increases in global softwood lumber production of 8, 23, and 53 million m3 per year by 2060, under the Conservative, Optimistic, and Extreme scenarios, respectively, leading to world price increases of 2%, 7%, and 23%, respectively. This projected price increase is relative to the projected price in the reference scenario, altering prices, production, consumption, trade of forest products, timber harvest, forest growth, and forest stock in individual countries. An increase in softwood lumber prices due to increased mass timber demand would lead to the reduced consumption of softwood lumber for traditional end-use (e.g., light-frame construction), suggesting a likely strong market competition for softwood lumber between the mass timber and traditional construction industries. In contrast, the projected effect on global forest stock was relatively small based on the relatively fast projected biomass growth in stands assumed to be regenerated after harvest.

In the past 50 years, cross-coupling reactions mediated by transition metals have changed the way in which complex organic molecules are synthesized. The predictable and chemoselective nature of these transformations has led to their widespread adoption across many areas of chemical research. However, the construction of a bond between two sp(3)-hybridized carbon atoms, a fundamental unit of organic chemistry, remains an important yet elusive objective for engineering cross-coupling reactions. In comparison to related procedures with sp(2)-hybridized species, the development of methods for sp(3)-sp(3) bond formation via transition metal catalysis has been hampered historically by deleterious side-reactions, such as β-hydride elimination with palladium catalysis or the reluctance of alkyl halides to undergo oxidative addition. To address this issue, nickel-catalysed cross-coupling processes can be used to form sp(3)-sp(3) bonds that utilize organometallic nucleophiles and alkyl electrophiles. In particular, the coupling of alkyl halides with pre-generated organozinc, Grignard and organoborane species has been used to furnish diverse molecular structures. However, the manipulations required to produce these activated structures is inefficient, leading to poor step- and atom-economies. Moreover, the operational difficulties associated with making and using these reactive coupling partners, and preserving them through a synthetic sequence, has hindered their widespread adoption. A generically useful sp(3)-sp(3) coupling technology that uses bench-stable, native organic functional groups, without the need for pre-functionalization or substrate derivatization, would therefore be valuable. Here we demonstrate that the synergistic merger of photoredox and nickel catalysis enables the direct formation of sp(3)-sp(3) bonds using only simple carboxylic acids and alkyl halides as the nucleophilic and electrophilic coupling partners, respectively. This metallaphotoredox protocol is suitable for many primary and secondary carboxylic acids. The merit of this coupling strategy is illustrated by the synthesis of the pharmaceutical tirofiban in four steps from commercially available starting materials.

The long-sought direct formation of a bond between two sp 3 -hybridized carbon atoms is achieved by the merger of photoredox and nickel catalysis using only simple carboxylic acids and alkyl halides as starting materials. Dual catalyst for sp 3 – sp 3 bond formation There is a demand in drug discovery and other fields for the molecular complexity associated with compounds featuring sp 3 – sp 3 carbon–carbon bonds, but the direct formation of a bond between two sp 3 -hybridized carbons has been a greater synthetic challenge than the formation of sp 2 – sp 2 bonds. This paper describes the development of a dual catalytic platform for coupling sp 3 – sp 3 centres that merges photoredox and nickel catalysis and is achieved using only simple carboxylic acids and alkyl halides as starting materials. The new protocol is suitable for many primary and secondary carboxylic acids and has been used to synthesize the pharmaceutical tirofiban in four steps from commercially available building blocks. In the past 50 years, cross-coupling reactions mediated by transition metals have changed the way in which complex organic molecules are synthesized. The predictable and chemoselective nature of these transformations has led to their widespread adoption across many areas of chemical research 1 . However, the construction of a bond between two sp 3 -hybridized carbon atoms, a fundamental unit of organic chemistry, remains an important yet elusive objective for engineering cross-coupling reactions 2 . In comparison to related procedures with sp 2 -hybridized species, the development of methods for sp 3 – sp 3 bond formation via transition metal catalysis has been hampered historically by deleterious side-reactions, such as β-hydride elimination with palladium catalysis or the reluctance of alkyl halides to undergo oxidative addition 3 , 4 . To address this issue, nickel-catalysed cross-coupling processes can be used to form sp 3 – sp 3 bonds that utilize organometallic nucleophiles and alkyl electrophiles 5 , 6 , 7 . In particular, the coupling of alkyl halides with pre-generated organozinc 8 , 9 , Grignard 10 and organoborane 11 species has been used to furnish diverse molecular structures. However, the manipulations required to produce these activated structures is inefficient, leading to poor step- and atom-economies. Moreover, the operational difficulties associated with making and using these reactive coupling partners, and preserving them through a synthetic sequence, has hindered their widespread adoption. A generically useful sp 3 – sp 3 coupling technology that uses bench-stable, native organic functional groups, without the need for pre-functionalization or substrate derivatization, would therefore be valuable. Here we demonstrate that the synergistic merger of photoredox and nickel catalysis enables the direct formation of sp 3 – sp 3 bonds using only simple carboxylic acids and alkyl halides as the nucleophilic and electrophilic coupling partners, respectively. This metallaphotoredox protocol is suitable for many primary and secondary carboxylic acids. The merit of this coupling strategy is illustrated by the synthesis of the pharmaceutical tirofiban in four steps from commercially available starting materials.

Two recent back-to-back meetings conveyed a common set of ongoing challenges for the fields of organocatalysis, photoredox catalysis and photochemistry.

While extreme weather events are often localized, the potential effects on global forests can be far reaching due to the interconnected nature of forest product markets. To better understand these dynamics, this study leverages historical forest‐based wind damage data in the United States and applies this information as shocks within a global forest sector outlook model. A large, localized wind event modeled as a shock to the US South creates a one‐time increase of 18.7 million m3 from salvage harvest operations, equal to over 4% of national harvest. This crowds out traditional harvest activities, leading to downward pressure on prices in the short run, followed by a persistent effect that could take approximately 25 years to dissipate from markets. Average annual wind damage contributes downward pressure on roundwood prices between 1% and 4% in the United States, and this effect is distributed to other countries. The findings suggest that large, localized shocks reverberate across regions and wood product markets due to their interconnected supply chains and trade patterns, and these impacts have important temporal dynamics. Another key result is that the magnitude of these effects are offset by endogenous market reactions in other markets. In other words, unaffected regions change their harvesting patterns in order to compensate for changes in the availability of fiber, shedding light on the importance of capturing global channels as large shocks materialize in changes in market dynamics internationally. Monte Carlo simulations suggest a wide confidence band on salvage harvest rates and prices. Plain Language Summary Extreme weather events can have significant impacts on global forests despite being localized, thanks to the interconnected nature of forest product markets. This study investigates this relationship by analyzing historical wind damage data from US forests. It finds that a major wind event in the US South led to a substantial increase in salvage harvest, equivalent to over 4% of the national harvest. This surge in harvest disrupted traditional activities, causing short‐term price drops and long‐lasting effects over about 25 years due to tree loss. Wind damage annually contributes to 1%–4% price decreases in US roundwood, affecting other countries too. The study emphasizes how such shocks ripple across regions and markets due to intertwined supply chains and trade patterns. It also highlights how unaffected regions adapt their harvesting to balance fiber availability, underscoring the importance of understanding global dynamics. Monte Carlo simulations reveal wide confidence bands on salvage harvest rates and prices, underlining the uncertainty surrounding these estimates. Key Points Extreme weather events, while localized, but can have far reaching consequences on forests due to the interconnected wood product markets The effect of extreme weather events on wood product markets is mitigated through endogenous market reactions in other regions

There has been a significant increase in the use of wood pellets for energy in the past decade due in large part to their climate mitigation potential. Because of this, the demand for wood pellets is largely driven by policy, as well as socioeconomic development, making projections of future wood energy markets highly uncertain. The aim of this study is to provide projections of future wood energy market trends under five distinct socioeconomic scenarios based on the assumed future evolution of gross domestic product, population, technological change, trade openness, and bioenergy preferences using the FOrest Resource Outlook Model. In four out of the five scenarios considered, it is projected that the use of roundwood and mill chips, particles, and residuals will rise in order to produce a growing output of wood pellets in the United States and globally. In terms of international markets, the global dominance of Europe’s demand for wood, to help that continent achieve its own climate goals, further explains the sustained and growing supply position of the U.S. South regions to meet that demand. Taken together, the projections suggest emerging bioenergy markets will drive increased competition for inputs with other manufacturers, particularly in the U.S. South regions.

5- Endo - trig cyclizations are generally considered to be kinetically unfavourable, as described by Baldwin's rules. Consequently, observation of this mode of reaction under kinetic control is rare. This is usually ascribed to challenges in achieving appropriate approach trajectories for orbital overlap in the transition state. Here, we describe a highly enantio- and diastereoselective route to complex indanes bearing all-carbon quaternary stereogenic centres via a 5- endo - trig cyclization catalysed by a chiral ammonium salt. Through computation, the preference for the formally disfavoured 5- endo - trig Michael reaction over the formally favoured 5- exo - trig Dieckmann reaction is shown to result from thermodynamic contributions to the innate selectivity of the nucleophilic group, which outweigh the importance of the approach trajectory as embodied by Baldwin's rules. Our experimental and theoretical findings demonstrate that geometric and stereoelectronic constraints may not be decisive in the observed outcome of irreversible ring-closing reactions. A highly enantio- and diastereoselective route to complex indanes via a 5- endo-trig Michael reaction catalysed by a chiral ammonium salt is described. The preference for this formally disfavoured cyclization over a formally favoured alternative shows that geometric and stereoelectronic constraints may not be decisive in the observed outcome of irreversible ring closing reactions.

To examine how the associations between meal consumption and BMI over 8 years differ by weight status in a sample of adolescents. Longitudinal, population-based study. Breakfast, lunch and dinner consumption and BMI were self-reported. Linear regressions were used to examine how the associations between meal consumption and BMI differed by weight status. Adolescents in the Minneapolis/St. Paul metropolitan area. Adolescents ( 1,471) were surveyed as part of the EAT 2010-2018 in 2009-2010 (M = 14·3 years) and 2017-2018 (M = 22·0 years). The prevalence of regular breakfast, lunch and dinner consumption (≥ 5 times/week) ranged from 45 to 65 %, 75 to 89 % and 76 to 94 %, respectively, depending on weight status category. Among adolescents with a sex- and age-specific BMI < 15th percentile, regular consumptions of breakfast, lunch and dinner during adolescence were positively associated with BMI in emerging adulthood compared with irregular consumption of breakfast, lunch and dinner (<5 times/week) after adjustment for socio-demographic characteristics ( = 5·43, = 5·39 and = 6·46, respectively; all -values <0·01). Among adolescents in the BMI 15-85th and 85-95th percentiles, regular consumptions of breakfast, lunch and dinner were positively associated with BMI but to a lesser extent ( -values <0·01). For participants with a BMI ≥ 95th percentile, regular consumptions of breakfast, lunch and dinner were positively associated with BMI, but the associations were not statistically significant ( -values > 0·05). The relationship between meal consumption during adolescence and BMI in emerging adulthood differs by adolescent weight status. Future studies should investigate underlying factors related to meal consumption routines and BMI.

Coronal loops form the basic building blocks of the magnetically closed solar corona yet much is still to be determined concerning their possible fine-scale structuring and the rate of heat deposition within them. Using an improved multi-stranded loop model to better approximate the numerically challenging transition region, this article examines synthetic NASA Solar Dynamics Observatory ’s (SDO) Atmospheric Imaging Assembly (AIA) emission simulated in response to a series of prescribed spatially and temporally random, impulsive and localised heating events across numerous sub-loop elements with a strong weighting towards the base of the structure: the nanoflare heating scenario. The total number of strands and nanoflare repetition times is varied systematically in such a way that the total energy content remains approximately constant across all the cases analysed. Repeated time-lag detection during an emission time series provides a good approximation for the nanoflare repetition time for low-frequency heating. Furthermore, using a combination of AIA 171/193 and 193/211 channel ratios in combination with spectroscopic determination of the standard deviation of the loop-apex temperature over several hours alongside simulations from the outlined multi-stranded loop model, it is demonstrated that both the imposed heating rate and number of strands can be realised.