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1. MiddleNet: A High-Performance, Lightweight, Unified NFV and Middlebox Framework

   https://doi.org/10.1109/NetSoft54395.2022.9844083  

   Zeng, Ziteng; Monis, Leslie; Qi, Shixiong; Ramakrishnan, K. K. (June 2022, 2022 IEEE 8th International Conference on Network Softwarization (NetSoft))

   Traditional network resident functions (e.g., firewalls, network address translation) and middleboxes (caches, load balancers) have moved from purpose-built appliances to software-based components. However, L2/L3 network functions (NFs) are being implemented on Network Function Virtualization (NFV) platforms that extensively exploit kernel-bypass technology. They often use DPDK for zero-copy delivery and high performance. On the other hand, L4/L7 middleboxes, which usually require full network protocol stack support, take advantage of a full-fledged kernel-based system with a greater emphasis on functionality. Thus, L2/L3 NFs and middleboxes continue to be handled by distinct platforms on different nodes.This paper proposes MiddleNet that seeks to overcome this dichotomy by developing a unified network resident function framework that supports L2/L3 NFs and L4/L7 middleboxes. MiddleNet supports function chains that are essential in both NFV and middlebox environments. MiddleNet uses DPDK for zero-copy packet delivery without interrupt-based processing, to enable the ‘bump-in-the-wire’ L2/L3 processing performance required of NFV. To support L4/L7 middlebox functionality, MiddleNet utilizes a consolidated, kernel-based protocol stack processing, avoiding a dedicated protocol stack for each function. MiddleNet fully exploits the event-driven capabilities provided by the extended Berkeley Packet Filter (eBPF) and seamlessly integrates it with shared memory for high-performance communication in L4/L7 middlebox function chains. The overheads for MiddleNet are strictly load-proportional, without needing the dedicated CPU cores of DPDK-based approaches. MiddleNet supports flow-dependent packet processing by leveraging Single Root I/O Virtualization (SR-IOV) to dynamically select packet processing needed (Layer 2 to Layer 7). Our experimental results show that MiddleNet can achieve high performance in such a unified environment. 

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2. Holobiont Traits Shape Climate Change Responses in Cryptic Coral Lineages

   https://doi.org/10.1111/gcb.17578  

   Grupstra, Carsten_G B; Meyer‐Kaiser, Kirstin S; Bennett, Matthew‐James; Andres, Maikani O; Juszkiewicz, David J; Fifer, James E; Da‐Anoy, Jeric P; Gomez‐Campo, Kelly; Martinez‐Rugerio, Isabel; Aichelman, Hannah E; et al (November 2024, Global Change Biology)

   ABSTRACT As ocean warming threatens reefs worldwide, identifying corals with adaptations to higher temperatures is critical for conservation. Genetically distinct but morphologically similar (i.e. cryptic) coral populations can be specialized to extreme habitats and thrive under stressful conditions. These corals often associate with locally beneficial microbiota (Symbiodiniaceae photobionts and bacteria), obscuring the main drivers of thermal tolerance. Here, we leverage a holobiont (massivePorites) with high fidelity for C15 photobionts to investigate adaptive variation across classic (“typical” conditions) and extreme reefs characterized by higher temperatures and light attenuation. We uncovered three cryptic lineages that exhibit limited micro‐morphological variation; one lineage dominated classic reefs (L1), one had more even distributions (L2), and a third was restricted to extreme reefs (L3). L1 and L2 were more closely related to populations ~4300 km away, suggesting that some lineages are widespread. All corals harboredCladocopiumC15 photobionts; L1 and L2 shared a photobiont pool that differed in composition between reef types, yet L3 mostly harbored unique photobiont strains not found in the other lineages. Assemblages of bacterial partners differed among reef types in lineage‐specific ways, suggesting that lineages employ distinct microbiome regulation strategies. Analysis of light‐harvesting capacity and thermal tolerance revealed adaptive variation underpinning survival in distinct habitats: L1 had the highest light absorption efficiency and lowest thermal tolerance, suggesting that it is a classic reef specialist. L3 had the lowest light absorption efficiency and the highest thermal tolerance, showing that it is an extreme reef specialist. L2 had intermediate light absorption efficiency and thermal tolerance, suggesting that is a generalist lineage. These findings reveal diverging holobiont strategies to cope with extreme conditions. Resolving coral lineages is key to understanding variation in thermal tolerance among coral populations, can strengthen our understanding of coral evolution and symbiosis, and support global conservation and restoration efforts. 

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3. Vanadium Electronic Configuration Determination From L2,3 Transition in V-oxide Compounds and Roscoelite

   https://doi.org/10.1093/micmic/ozac057  

   Zanetta, Pierre-Marie; Drexler, Maxwell S; Barton, Isabel F; Zega, Thomas J (January 2023, Microscopy and Microanalysis)

   Abstract We report on the electronic structure of vanadium in synthetic V-oxides and in natural roscoelite (V-rich phyllosilicate). This study applied electron energy-loss spectroscopy (EELS) in the scanning transmission electron microscope (STEM), combined with first-principle calculations, to (1) establish relationships between the V oxidation state and EELS L2,3 features and (2) better constrain the oxidation state and crystallographic siting of V in roscoelite, with implications for other V-bearing phyllosilicates. Both EELS measurements and band structure calculations show that the EELS L2/L3 ratio increases as the oxidation state of V increases. We establish a quantitative relationship between the V L2,3 near-edge structure and the V oxidation state by normalizing the L2 maximum peak intensity to the L3 peak intensity. By applying this method to roscoelite, we find that it hosts a mix of trivalent and tetravalent V distributed between the octahedral and tetrahedral sites with a V4+/ΣV = 0.6 ± 0.1. This relationship is applicable to measurements of V oxidation states in oxide and phyllosilicate minerals, which is useful for constraining the conditions of rock and mineral formation and has potential implications for metal extraction from phyllosilicate ores. 

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4. Selective binding of anions by rigidified nanojars: sulfate vs. carbonate

   https://doi.org/10.1039/d1ob01318a  

   Al Isawi, Wisam A.; Salome, Austin Z.; Ahmed, Basil M.; Zeller, Matthias; Mezei, Gellert (September 2021, Organic & Biomolecular Chemistry)

   Selective binding and transport of highly hydrophilic anions is ubiquitous in nature, as anion binding proteins can differentiate between similar anions with over a million-fold efficiency. While comparable selectivity has occasionally been achieved for certain anions using small, artificial receptors, the selective binding of certain anions, such as sulfate in the presence of carbonate, remains a very challenging task. Nanojars of the formula [anion⊂{Cu(OH)(pz)} n ] 2− (pz = pyrazolate; n = 27–33) are totally selective for either CO 3 2− or SO 4 2− over anions such as NO 3 − , ClO 4 − , BF 4 − , Cl − , Br − and I − , but cannot differentiate between the two. We hypothesized that rigidification of the nanojar outer shell by tethering pairs of pyrazole moieties together will restrict the possible orientations of the OH hydrogen-bond donor groups in the anion-binding cavity of nanojars, similarly to anion-binding proteins, and will lead to selectivity. Indeed, by using either homoleptic or heteroleptic nanojars of the general formula [anion⊂Cu n (OH) n (L2–L6) y (pz) n −2 y ] 2− ( n = 26–31) based on a series of homologous ligands HpzCH 2 (CH 2 ) x CH 2 pzH ( x = 0–4; H 2 L2–H 2 L6), selectivity for carbonate (with L2 and with L4–L6/pz mixtures) or for sulfate (with L3) has been achieved. The synthesis of new ligands H 2 L3, H 2 L4 and H 2 L5, X-ray crystal structures of H 2 L4 and the tetrahydropyranyl-protected derivatives (THP) 2 L4 and (THP) 2 L5, synthesis and characterization by electrospray-ionization mass spectrometry (ESI-MS) of carbonate- and sulfate-nanojars derived from ligands H 2 L2–H 2 L6, as well as detailed selectivity studies for CO 3 2− vs. SO 4 2− using these novel nanojars are presented. 

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5. Efficient and Flexible Aggregation and Distribution of MODIS Atmospheric Products Based on Climate Analytics as a Service Framework

   https://doi.org/10.3390/rs13173541  

   Zheng, Jianyu; Huang, Xin; Sangondimath, Supriya; Wang, Jianwu; Zhang, Zhibo (September 2021, Remote Sensing)

   null (Ed.)

   MODIS (Moderate Resolution Imaging Spectroradiometer) is a key instrument onboard NASA’s Terra (launched in 1999) and Aqua (launched in 2002) satellite missions as part of the more extensive Earth Observation System (EOS). By measuring the reflection and emission by the Earth-Atmosphere system in 36 spectral bands from the visible to thermal infrared with near-daily global coverage and high-spatial-resolution (250 m ~ 1 km at nadir), MODIS is playing a vital role in developing validated, global, interactive Earth system models. MODIS products are processed into three levels, i.e., Level-1 (L1), Level-2 (L2) and Level-3 (L3). To shift the current static and “one-size-fits-all” data provision method of MODIS products, in this paper, we propose a service-oriented flexible and efficient MODIS aggregation framework. Using this framework, users only need to get aggregated MODIS L3 data based on their unique requirements and the aggregation can run in parallel to achieve a speedup. The experiments show that our aggregation results are almost identical to the current MODIS L3 products and our parallel execution with 8 computing nodes can work 88.63 times faster than a serial code execution on a single node. 

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