Optogenetics has revolutionized the experimental interrogation of neural circuits and holds promise for the treatment of neurological disorders. It is limited, however, because visible light cannot penetrate deep inside brain tissue. Upconversion nanoparticles (UCNPs) absorb tissue-penetrating near-infrared (NIR) light and emit wavelength-specific visible light. Here, we demonstrate that molecularly tailored UCNPs can serve as optogenetic actuators of transcranial NIR light to stimulate deep brain neurons. Transcranial NIR UCNP-mediated optogenetics evoked dopamine release from genetically tagged neurons in the ventral tegmental area, induced brain oscillations through activation of inhibitory neurons in the medial septum, silenced seizure by inhibition of hippocampal excitatory cells, and triggered memory recall. UCNP technology will enable less-invasive optical neuronal activity manipulation with the potential for remote therapy.
The ability to recognize information incongruous with previous experience is critical for survival, thus novelty signals in the mammalian brain have evolved to enhance attention, perception and memory 1-3 . Although the importance of regions such as the ventral tegmental area 4-6 and locus coeruleus 6,7 in broadly signaling novelty has been well established, these diffuse monoaminergic transmitters have yet to be shown to convey specific information regarding the type of stimuli that drive them 6 . Whether distinct types of novelty, such as contextual and social novelty, are differently processed and routed in the brain remain unclear. Here we identify a novelty hub in the hypothalamus -the supramammillary nucleus (SuM) 8 . Unique about this region is that it not only responds broadly to novel stimuli, but segregates and selectively routes different types of information to discrete cortical targets, the dentate gyrus (DG) and CA2 fields of the hippocampus, for the modulation of mnemonic processing. Taking advantage of a novel SuM-Cre transgenic mouse, we found that DG-projecting SuM neurons are activated by contextual novelty while the SuM-CA2 circuit is preferentially activated by novel social encounters. Circuitbased manipulation demonstrated that divergent novelty channeling in these projections significantly modifies hippocampal-based contextual or social memory. This content-
Since 2020, the COVID-19 pandemic has urged event holders to shift conferences online. Virtual and hybrid conferences are greener alternatives to in-person conferences, yet their environmental sustainability has not been fully assessed. Considering food, accommodation, preparation, execution, information and communication technology, and transportation, here we report comparative life cycle assessment results of in-person, virtual, and hybrid conferences and consider carbon footprint trade-offs between in-person participation and hybrid conferences. We find that transitioning from in-person to virtual conferencing can substantially reduce the carbon footprint by 94% and energy use by 90%. For the sake of maintaining more than 50% of in-person participation, carefully selected hubs for hybrid conferences have the potential to slash carbon footprint and energy use by two-thirds. Furthermore, switching the dietary type of future conferences to plant-based diets and improving energy efficiencies of the information and communication technology sector can further reduce the carbon footprint of virtual conferences.
Sustainability of reusing Li-ion batteries is hindered by high nickel content and is susceptible to use and recycling choices.
This study examines prominent thermochemical conversion technologies, such as slow pyrolysis, fast pyrolysis, gasification, and hydrothermal liquefaction, for treating poultry litter in New York State (NYS). Nine cases involving combinations of the four technologies and different downstream processing options such as bio-oil upgrading and Fischer–Tropsch conversion are chosen based on the product distribution. High-fidelity process simulations are performed to derive the mass and energy balance. Economic performance for the nine cases varied widely with largely overlapping net present values, ranging from $10MM to $170MM (slow pyrolysis), $89MM to $314.5MM (fast pyrolysis), $28MM to $196MM (hydrothermal liquefaction), and $25MM to $234MM (gasification). Both pyrolysis technologies had 18% to 56% lower greenhouse gas (GHG) emissions than the other technologies. GHG balances showed trade-offs with economic performance. Sensitivity analysis identified carbon credits, products’ market price, and plant capacity as the most influential factors. Building one centralized biorefinery in NYS especially for fast pyrolysis was more economically feasible than building multiple smaller biorefineries (biochar breakeven price of −$128 to −$91/ton vs $74 to $93/ton). The trend for slow pyrolysis was similar but with comparatively little difference (biochar breakeven price of $59 to $96/ton for one biorefinery vs $76 to $91/ton for multiple biorefineries).
Sustained demands for pharmaceutical commodities are continuously created due to economic development and the rapidly aging world population. However, the climate and environmental implications of globalized pharmaceutical manufacturing have not been sufficiently understood to inform the integration of key learnings into sustainability practices. Here, we systematically study the environmental impacts of the pharmaceutical supply chain and identify hotspots through a novel analysis framework. Using the case of an HIV drug, tenofovir disoproxil fumarate, we demonstrate that improving the solvent recovery rate, innovating the adenine synthesis route, optimizing the adenine yield, and substituting non-renewable heating fuels with renewables can help mitigate the carbon footprint and cumulative energy demand by up to 45%. Carefully optimized pharmaceutical supply chain networks can result in a reduction of up to 9.3% in the life cycle carbon footprint. The majority of carbon emission reductions could be attributed to manufacturing and formulating in regions with deeply decarbonized power grids, rather than reducing the transportation distances between production or formulation sites and raw material or demand zones. Pharmaceutical manufacturers could be incentivized to purchase renewable electricity and source climate pledge friendly raw materials to reduce their carbon footprint.
The widespread COVID-19 pandemic led to a shortage in the supply of N95 respirators in the United States until May 2021. In this study, we address the energy, environmental, and economic benefits of the decontamination-and-reuse of the N95 masks. Two popular decontamination methods, including dry heat and vapor hydrogen peroxide (VHP), are investigated in this study for their effective pathogen inactivation and favorable performance in preserving filtration efficiency and structural integrity of respirators. Two multiple reuse cases, under which the N95 masks are disinfected and used five times with the dry heat method and 20 times using the VHP method, are considered and compared with a single-use case. Compared to the single-use case, the dry heat-based multiple-use case reduces carbon footprint by 50% and cumulative energy demand (CED) by 17%, while the VHP-based case decreases carbon footprint by 67% and CED by 58%. The dry-heat-based and VHP-based multiple reuse cases also present environmental benefits in most of the other impact categories, primarily due to substituting new N95 respirators with decontaminated ones. Decontaminating and reusing respirators costs 77% and 89% less than the case of single-use and disposal. The sensitivity analysis results show that the geographical variation in the power grid and the times of respirator use are the most influential factors for carbon footprint and CED, respectively. The result also reaffirms the energy, environmental, and economic favorability of the decontamination and reuse of N95 respirators.
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