1,023 research outputs found

    N,N′-Bis(2-cyano­ethyl)-4,4′-dimethyl-N,N′-(butane-1,4-di­yl)dibenzene­sulfonamide

    Get PDF
    The complete mol­ecule of the title compound, C24H30N4O4S2, is generated by a crystallographic inversion centre. In the crystal, weak C—H⋯O inter­actions link the mol­ecules, forming infinite sheets

    2,2′,4,4′,6,6′-Hexamethyl-N-(3-phthalimidoprop­yl)-N,N′-(propane-1,3-di­yl)dibenzene­sulfonamide

    Get PDF
    In the title compound, C32H38N3O6S2, an inter­mediate in the synthesis of polyamine drugs, the dihedral angle between the phenyl rings of the two 2,4,6-trimethyl­benzene­sulfonyl groups is 27.1 (3)°. In the crystal structure, mol­ecules are linked by inter­molecular N—H⋯O hydrogen bonds, thereby forming an infinite one-dimensional chain propagating along [010]

    2-(3-Bromo­prop­yl)isoindoline-1,3-dione

    Get PDF
    In the title compound, C11H10BrNO2, the dihedral angle between the five- and six-membered rings of the phthalamide system is 1.00 (16)°. There are no significant inter­molecular inter­ations except for van der Waals contacts

    Code as Policies: Language Model Programs for Embodied Control

    Full text link
    Large language models (LLMs) trained on code completion have been shown to be capable of synthesizing simple Python programs from docstrings [1]. We find that these code-writing LLMs can be re-purposed to write robot policy code, given natural language commands. Specifically, policy code can express functions or feedback loops that process perception outputs (e.g.,from object detectors [2], [3]) and parameterize control primitive APIs. When provided as input several example language commands (formatted as comments) followed by corresponding policy code (via few-shot prompting), LLMs can take in new commands and autonomously re-compose API calls to generate new policy code respectively. By chaining classic logic structures and referencing third-party libraries (e.g., NumPy, Shapely) to perform arithmetic, LLMs used in this way can write robot policies that (i) exhibit spatial-geometric reasoning, (ii) generalize to new instructions, and (iii) prescribe precise values (e.g., velocities) to ambiguous descriptions ("faster") depending on context (i.e., behavioral commonsense). This paper presents code as policies: a robot-centric formalization of language model generated programs (LMPs) that can represent reactive policies (e.g., impedance controllers), as well as waypoint-based policies (vision-based pick and place, trajectory-based control), demonstrated across multiple real robot platforms. Central to our approach is prompting hierarchical code-gen (recursively defining undefined functions), which can write more complex code and also improves state-of-the-art to solve 39.8% of problems on the HumanEval [1] benchmark. Code and videos are available at https://code-as-policies.github.i

    Characterization of a newly isolated green microalga Scenedesmus sp. as a potential source of biodiesel

    Get PDF
    An oil-producing microalga SP-01 belonging to the genus Scenedesmus was shown to be able to grow on a media containing 5 to 30 g L-1 NaCl. Under mixotrophic condition, the maximum cell dry weight of 3.1 g L-1 and specific growth rate of 0.034 h-1 were obtained at 0.5 g L-1 NaNO3 and 6 g L-1 acetate. The effects of salinity on the biomass, lipid, and carotenoid productions of the alga SP-01 in mixotrophic mode were investigated. The biomass productivity increased with increasing NaNO3 concentrations, and addition of NaCl resulted in a higher biomass while NaNO3 was present. The maximum lipid content was obtained while no NaNO3 and NaCl was added, and the lipid content decreased with increasing NaNO3 concentrations or addition of NaCl. The maximum lipid productivities of 67.44 to 68.44 mg L-1day-1 were obtained while NaNO3 and NaCl were not added or while 20 g L-1 NaCl and 0.13 g L-1 NaNO3 were added. The algal lipid was mainly composed of C16 and C18 fatty acids accounting for more than 90% of total fatty acids. Furthermore, lutein and astaxanthin were the main carotenoids.Key words: Halotolerant, microalga, Scenedesmus sp., mixotrophic culture, lipid, carotenoid

    Lignans from the Roots and Rhizomes of Clematis manshurica

    Get PDF
    Two new lignans, clemomanshurinane A and B, along with ten known compounds have been isolated from the roots and rhizomes of Clematis manshurica. The structures were elucidated on the basis of their physicochemical and spectroscopic evidence. Clemomanshurinane A and B, (+)-dihydrodehydrodiconiferyl alcohol and (+)-lariciresinol 4,4'-O-bis-β -D-glucopyranoside indicated inhibitory effects on COX-2 at final concentration of 10 −5 mol/l, with the inhibition rates 65.8%, 71.8%, 53.3%, and 60.3%, respectively

    Mitigation of chronic unpredictable stress–induced cognitive deficits in mice by Lycium barbarum L (Solanaceae) polysaccharides

    Get PDF
    Purpose: To investigate the neuroprotective effects of Lycium barbarum polysaccharide (LBP) against concomitant cognitive dysfunction and changes in hippocampal CREB-BDNF signaling pathway in chronically unpredictable stressed mice.Methods: The mice were subjected to different unpredictable stressors for a period of 4 weeks. Behavioral tests, including open field (OFT) and Morris water maze (MWMT) tests were used to evaluate pharmacological effects. Serum corticosterone levels, protein expression level of BDNF and pCREB/CREB in hippocampus were assessed by ELISA, Western blot and immunohistochemistry methods, respectively. Morphological changes in pyramidal neurons in the hippocampus were studied by Nissl staining.Results: LBP improved mice performance in MWMT, indicating that it reversed chronic unpredictable stress (CUS)-induced cognitive deficits. LBP treatment reduced serum corticosterone levels and prevented neuron loss in the hippocampus. It maintained expression levels of BDNF and phosphorylation of CREB in hippocampus during CUS procedure.Conclusion: Lycium barbarum polysaccharide protects CREB-BDNF signaling pathway in hippocampus and relieves CUS-induced cognitive deficits. These results suggest that Lycium barbarum polysaccharides is potentially an alternative neuro-protective agent against stress-induced psychopathological dysfunction.Keywords: Lycium barbarum, Polysaccharide, Chronic unpredictable stress, Cognitive deficits, Brainderived neurotrophic factor, Calcium/cyclic-AMP responsive binding protei
    corecore