10,000 publications from this institution
Carbon dioxide flux and meteorological data for the Harvard Forest, MA (1992-95) and BOREAS Northern Study Area, Old Black Spruce (Alberta, Canada; 1994-95) FLUXNET sites are provided as examples of the larger FLUXNET data archive available at the ORNL Distributed Active Archive Center [ http://daac.ornl.gov/FLUXNET/fluxnet.html]. FLUXNET is a global network of micrometeorological tower sites that use eddy covariance methods to measure the exchanges of carbon dioxide (CO2), water vapor, and energy between terrestrial ecosystem and atmosphere. Gap-filled flux data and meteorological data for half-hourly, daily, weekly, monthly, and annual time intervals are presented for each site and year. There are 6 *.zip files with this data set.
Video analytics applications use edge compute servers for the analytics of the videos (for bandwidth and privacy). Compressed models that are deployed on the edge servers for inference suffer from data drift, where the live video data diverges from the training data. Continuous learning handles data drift by periodically retraining the models on new data. Our work addresses the challenge of jointly supporting inference and retraining tasks on edge servers, which requires navigating the fundamental tradeoff between the retrained model's accuracy and the inference accuracy. Our solution Ekya balances this tradeoff across multiple models and uses a micro-profiler to identify the models that will benefit the most by retraining. Ekya's accuracy gain compared to a baseline scheduler is 29% higher, and the baseline requires 4x more GPU resources to achieve the same accuracy as Ekya.
The word “predator” may conjure images of leopards killing and eating impala on the African savannah or of great white sharks attacking elephant seals off the coast of California. But microorganisms are also predators, including bacteria that kill and eat other bacteria.
Cellulose synthase (CESA) complexes can be observed by live-cell imaging to move with trajectories that parallel the underlying cortical microtubules. Here we report that CESA interactive protein 1 (CSI1) is a microtubule-associated protein that bridges CESA complexes and cortical microtubules. Simultaneous in vivo imaging of CSI1, CESA complexes, and microtubules demonstrates that the association of CESA complexes and cortical microtubules is dependent on CSI1. CSI1 directly binds to microtubules as demonstrated by in vitro microtubule-binding assay.
It is shown that the tert-butyloxycarbonylation of phenols, alcohols, enols, and thiols can be accomplished by reaction of these functionalities with di-tert-butyl dicarbonate under phase transfer conditions. The reactions proceed in high yield and can also be used for the introduction of t-BOC groups onto functionalized polymer backbones such as novolac or poly(p-hydroxystyrene). In addition, a study is made of the selectivity towards tert-butyloxycarbonylation of various polyfunctional compounds.
Cyclic fatigue stress/life ( S / N ) and crack‐growth properties are investigated in magnesia‐partially‐stabilized zirconia (Mg‐PSZ), with particular reference to the role of crack size. The material studied is subeutectoid aged to vary the steady‐state fracture toughness, K c , from ∼3 to 16 MPa · m 1/2 · S / N data from unnotched specimens show markedly lower lives under tension—compression compared with tension—tension loading; “fatigue limits”(at 10 8 cycles) for the former case approach 50% of the tensile strength. Under tension—tension loading, cyclic crack‐growth rates of “long”(> 3 mm) cracks are found to be power‐law dependent on the stress‐intensity range, Δ K , with a fatigue threshold, Δ K TH , of order 50% of K c . Conversely, naturally occurring “small”(1 to 100 μm) surface cracks are observed to grow at Δ K levels 2 to 3 times smaller than Δ K TH , similar to behavior widely reported for metallic materials. The observed small‐crack behavior is rationalized in terms of the restricted role of crack‐tip shielding (in PSZ from transformation toughening) with cracks of limited wake, analogous to the reduced role of crack closure with small fatigue cracks in metals. The implications of such data for structural design with ceramics are briefly discussed.
Plant natural products have been used for centuries to treat human illnesses, as recreational substances, and as flavoring and coloring agents in our food. Nowadays, commercial-scale manufacturing of plant natural products using extraction from natural resources or chemical synthesis poses challenges for environmental sustainability, such as species overexploitation. Bio-based synthesis of plant natural products in microbial cell factories can offer an attractive alternative as these processes reduce the use of natural plant resources and instead rely on renewable feedstocks as raw materials. Here, we review the most recent developments on the sustainable supply of plant natural products by the bio-based synthesis in yeast, with a special focus on newly discovered and implemented plant natural product biosynthetic pathways, approaches for chemical diversification of natural products, and optimization of platform yeast cell factories. From this, we discuss environmental considerations and the main challenges toward sustainable and robust microbial production of plant natural products based on fermentation.
In article number 1400478, Gerbrand Ceder and co-workers demonstrate that the practical specific capacity of battery electrodes depends on ionic percolation properties. The central part of the image depicts the reversible capacity of lithium-transition-metal oxides with spinel-like structure as a function of the total lithium content and the structural disorder. Typical local atomic arrangements and lithium diffusion channels are shown in the satellite images. The background is a percolating network of fast lithium diffusion channels.
