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Earth system models (ESMs) typically simplify the representation of land surface spectral albedo to two values, which correspond to the photosynthetically active radiation (PAR, 400–700 nm) and the near infrared (NIR, 700–2,500 nm) spectral bands. However, the availability of hyperspectral observations now allows for a more direct retrieval of ecological parameters and reduction of uncertainty in surface reflectance. To investigate sensitivity and quantify biases of incorporating hyperspectral albedo information into ESMs, we examine how shortwave soil albedo affects surface radiative forcing and simulations of the carbon and water cycles. Results reveal that the use of two broadband values to represent soil albedo can introduce systematic radiative-forcing differences compared to a hyperspectral representation. Specifically, we estimate soil albedo biases of ±0.2 over desert areas, which can result in spectrally integrated radiative forcing divergences of up to 30 W m−2, primarily due to discrepancies in the blue (404–504 nm) and far-red (702–747 nm) regions. Furthermore, coupled land-atmosphere simulations indicate a significant difference in net solar flux at the top of the atmosphere (>3.3 W m−2), which can impact global energy fluxes, rainfall, temperature, and photosynthesis. Finally, simulations show that considering the hyperspectrally resolved soil reflectance leads to increased maximum daily temperatures under current and future CO2 concentrations.

Hypertension is the primary cause of cardiovascular disease, which is a leading killer worldwide. Despite the prevalence of this non-communicable disease, still between 90% and 95% of cases are of unknown or multivariate cause ("essential hypertension"). Current therapeutic options focus primarily on lowering blood pressure through decreasing peripheral resistance or reducing fluid volume, but fewer than half of hypertensive patients can reach blood pressure control. Hence, identifying unknown mechanisms causing essential hypertension and designing new treatment accordingly are critically needed for improving public health. In recent years, the immune system has been increasingly implicated in contributing to a plethora of cardiovascular diseases. Many studies have demonstrated the critical role of the immune system in the pathogenesis of hypertension, particularly through pro-inflammatory mechanisms within the kidney and heart, which, eventually, drive a myriad of renal and cardiovascular diseases. However, the precise mechanisms and potential therapeutic targets remain largely unknown. Therefore, identifying which immune players are contributing to local inflammation and characterizing pro-inflammatory molecules and mechanisms involved will provide promising new therapeutic targets that could lower blood pressure and prevent progression from hypertension into renal or cardiac dysfunction., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Benson, Guo, Deck, Mora, Liu and Mu.)

Hypertension is the leading cause of cardiovascular disease and the primary risk factor for mortality worldwide. For more than half a century, researchers have demonstrated that immunity plays an important role in the development of hypertension; however, the precise mechanisms are still under investigation. The current body of knowledge indicates that proinflammatory cytokines may play an important role in contributing to immune-related pathogenesis of hypertension. Interferon gamma (IFN- γ ), in particular, as an important cytokine that modulates immune responses, has been recently identified as a critical regulator of blood pressure by several groups, including us. In this review, we focus on exploring the role of IFN- γ in contributing to the pathogenesis of hypertension, outlining the various immune producers of this cytokine and described signaling mechanisms involved. We demonstrate a key role for IFN- γ in hypertension through global knockout studies and related downstream signaling pathways that IFN- γ production from CD8 + T cell (CD8T) in the kidney promoting CD8T-stimulated salt retention via renal tubule cells, thereby exacerbating hypertension. We discuss potential activators of these T cells described by the current literature and relay a novel hypothesis for activation., Competing Interests: All authors have nothing to disclose., (Copyright © 2022 by the American Society of Nephrology.)

Crystallization of supercooled liquid water in most natural environments starts with heterogeneous nucleation of ice induced by a nucleation site. Mineral surfaces, which form the majority of aqueous interfaces in Earth's ecosystem, possess a plethora of surface morphological and chemical features that can serve as ice nucleation sites. The nature of surface sites responsible for ice nucleation from supersaturated water vapor have been recently identified for alkali feldspar, a family of rock-building minerals constituting 60% of the Earth's crust. It was demonstrated that ice preferentially forms upon the patches of crystalline surface with (100) orientation, exposed in the surface defects such as cracks, pores, and pits arising due to chemically induced stress and further enhanced by hydrothermal alterations of natural feldspars. However, whether the same sites were responsible for nucleation from liquid water, remained to be shown. Here, we investigate the mechanism of heterogeneous ice nucleation in a layer of aqueous sucrose solution on top of thin sections of feldspar prepared along the (010) crystalline plane. We observe a preferential orientation of ice crystals defined by an epitaxial relationship between feldspar and ice, with ice crystals growing on the crystalline surfaces of feldspar with (100) orientation. We thus conclude that the ice nucleating sites active in deposition freezing mode are also active in the immersion freezing regime. This conclusion is further supported by the enhancement of ice nucleation active site density observed for the thin sections of feldspar prepared sub-parallel to the (100) plane as compared to sections prepared along (010) and (001) crystallographic orientations.