Chemical recycling of polymers to their constituent monomers is the foremost challenge in building a sustainable circular plastics economy. Here, we report a strategy for highly efficient ...depolymerization of various CO2‐based alicyclic polycarbonates to epoxide monomers in solvent‐free conditions by a simple CrIII‐Salen complex mediated catalytic pyrolysis process. The chemical recycling of the widely studied poly(cyclohexene carbonate) exhibits excellent reactivity (TOF up to 3000 h−1, 0.1 mol % catalyst loading) and high epoxide monomer selectivity (>99 %). Mechanistic investigation reveals that the process proceeds in a sequential fashion via a trans‐carbonate intermediate.
The catalytic pyrolysis of various CO2‐based polycarbonates in bulk recovers epoxide monomers quantitatively using a simple CrIII‐Salen catalyst. It even proceeds very efficiently for chemical recycling of poly(cyclohexene carbonate) from a plastic waste mixture and thus provides a closed‐loop approach towards a circular plastic economy in applications of CO2‐based polycarbonates.
That osteocalcin (OCN) is necessary for hippocampal-dependent memory and to prevent anxiety-like behaviors raises novel questions. One question is to determine whether OCN is also sufficient to ...improve these behaviors in wild-type mice, when circulating levels of OCN decline as they do with age. Here we show that the presence of OCN is necessary for the beneficial influence of plasma from young mice when injected into older mice on memory and that peripheral delivery of OCN is sufficient to improve memory and decrease anxiety-like behaviors in 16-mo-old mice. A second question is to identify a receptor transducing OCN signal in neurons. Genetic, electrophysiological, molecular, and behavioral assays identify
, an orphan G protein-coupled receptor expressed in neurons of the CA3 region of the hippocampus, as transducing OCN's regulation of hippocampal-dependent memory in part through inositol 1,4,5-trisphosphate and brain-derived neurotrophic factor. These results indicate that exogenous OCN can improve hippocampal-dependent memory in mice and identify molecular tools to harness this pathway for therapeutic purposes.
This paper studies a key issue of developing reconfigurable fault-tolerant control to retain a nominal feedback controller and simultaneously handles actuator faults and system uncertainty, while the ...closed-loop system is stabilized with all control objectives achieved. A theoretical architecture of a reconfigurable control design is presented for a class of uncertain mechanical systems by using an observer technique. As a stepping stone, a nonlinear observer-based estimation mechanism is designed to reconstruct uncertain dynamics and actuator faults with the estimation error converging to zero within finite time. A reconfigurable control effort is then synthesized from the reconstructed knowledge. This control power operates as a compensation control part, and it is added to the nominal control part to accommodate system uncertainties and actuator faults. It is proved that the overall system resulted from the developed control framework has the same control performance of the nominal closed-loop system, including certain system dynamics and the nominal control effort. The effectiveness of the scheme is validated on a serial robotic manipulator.
Abstract
The accurate, rapid, and sensitive identification of cancer cells in complex physiological environments is significant in biological studies, personalized medicine, and biomedical ...engineering. Inspired by the naturally confined enzymes on fluid cell membranes, a
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ed CRISPR‐based
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(FINDER) was developed on living cell membranes, which was successfully applied for rapid and sensitive cancer cell identification in clinical blood samples. Benefiting from the spatial confinement effect for improved local concentration, and membrane fluidity for higher collision efficiency, the activity of CRISPR‐Cas12a was, for the first time, found to be significantly enhanced on living cell membranes. This new phenomenon was then combined with multiple aptamer‐based DNA logic gate for cell recognition, thus a FINDER system capable of accurate, rapid and sensitive cancer cell identification was constructed. The FINDER rapidly identified target cells in only 20 min, and achieved over 80 % recognition efficiency with only 0.1 % of target cells presented in clinical blood samples, indicating its potential application in biological studies, personalized medicine, and biomedical engineering.
The hypocretin/orexin (Hcrt/Orx) system in the perifornical lateral hypothalamus has been recognized as a critical node in a complex network of neuronal systems controlling both physiology and ...behavior in vertebrates. Our understanding of the Hcrt/Orx system and its array of functions and actions have grown exponentially in merely two decades. This review will examine the latest progress in discerning the roles played by the Hcrt/Orx system in the regulation of homeostatic functions and in the execution of instinctive and learned behaviors. Furthermore, the gaps that currently exist in our knowledge of sex-related differences in this field of study are discussed.
Endometriosis is an estrogen-dependent inflammatory disorder among reproductive-aged women associated with pelvic pain, anxiety, and depression. Pain is characterized by central sensitization; ...however, it is not clear if endometriosis leads to increased pain perception or if women with the disease are more sensitive to pain, increasing the detection of endometriosis. Endometriosis was induced in mice and changes in behavior including pain perception, brain electrophysiology, and gene expression were characterized. Behavioral tests revealed that mice with endometriosis were more depressed, anxious and sensitive to pain compared to sham controls. Microarray analyses confirmed by qPCR identified differential gene expression in several regions of brain in mice with endometriosis. In these mice, genes such as Gpr88, Glra3 in insula, Chrnb4, Npas4 in the hippocampus, and Lcn2 in the amygdala were upregulated while Lct, Serpina3n (insula), and Nptx2 (amygdala) were downregulated. These genes are involved in anxiety, locomotion, and pain. Patch clamp recordings in the amygdala were altered in endometriosis mice demonstrating an effect of endometriosis on brain electrophysiology. Endometriosis induced pain sensitization, anxiety, and depression by modulating brain gene expression and electrophysiology; the effect of endometriosis on the brain may underlie pain sensitization and mood disorders reported in women with the disease. Summary Sentence Endometriosis disrupts brain gene expression and electrophysiology, inducing anxiety, depression, and pain sensitization in mice.
Steroid‐refractory (SR) acute graft‐versus‐host disease (aGVHD) is one of the leading causes of early mortality after allogeneic hematopoietic stem cell transplantation (allo‐HSCT). We investigated ...the efficacy, safety, prognostic factors, and optimal therapeutic protocol for SR‐aGVHD patients treated with basiliximab in a real‐world setting. Nine hundred and forty SR‐aGVHD patients were recruited from 36 hospitals in China, and 3683 doses of basiliximab were administered. Basiliximab was used as monotherapy (n = 642) or in combination with other second‐line treatments (n = 298). The cumulative incidence of overall response rate (ORR) at day 28 after basiliximab treatment was 79.4% (95% confidence interval CI 76.5%–82.3%). The probabilities of nonrelapse mortality and overall survival at 3 years after basiliximab treatment were 26.8% (95% CI 24.0%–29.6%) and 64.3% (95% CI 61.2%–67.4%), respectively. A 1:1 propensity score matching was performed to compare the efficacy and safety between the monotherapy and combined therapy groups. Combined therapy did not increase the ORR; conversely, it increased the infection rates compared with monotherapy. The multivariate analysis showed that combined therapy, grade III–IV aGVHD, and high‐risk refined Minnesota aGVHD risk score before basiliximab treatment were independently associated with the therapeutic response. Hence, we created a prognostic scoring system that could predict the risk of having a decreased likelihood of response after basiliximab treatment. Machine learning was used to develop a protocol that maximized the efficacy of basiliximab while maintaining acceptable levels of infection risk. Thus, real‐world data suggest that basiliximab is safe and effective for treating SR‐aGVHD.
Smoking decreases appetite, and smokers often report that they smoke to control their weight. Understanding the neurobiological mechanisms underlying the anorexic effects of smoking would facilitate ...the development of novel treatments to help with smoking cessation and to prevent or treat obesity. By using a combination of pharmacological, molecular genetic, electrophysiological, and feeding studies, we found that activation of hypothalamic α3β4 nicotinic acetylcholine receptors leads to activation of pro-opiomelanocortin (POMC) neurons. POMC neurons and subsequent activation of melanocortin 4 receptors were critical for nicotinic-induced decreases in food intake in mice. This study demonstrates that nicotine decreases food intake and body weight by influencing the hypothalamic melanocortin system and identifies critical molecular and synaptic mechanisms involved in nicotine-induced decreases in appetite.
Transition‐metal phosphides have stimulated great interest as catalysts to drive the hydrogen evolution reaction (HER), but their use as bifunctional catalytic electrodes that enable efficient ...neutral‐pH water splitting has rarely been achieved. Herein, we report the synthesis of ternary Ni0.1Co0.9P porous nanosheets onto conductive carbon fiber paper that can efficiently and robustly catalyze both the HER and water oxidation in 1 m phosphate buffer (PBS; pH 7) electrolyte under ambient conditions. A water electrolysis cell comprising the Ni0.1Co0.9P electrodes demonstrates remarkable activity and stability for the electrochemical splitting of neutral‐pH water. We attribute this performance to the new ternary Ni0.1Co0.9P structure with porous surfaces and favorable electronic states resulting from the synergistic interplay between nickel and cobalt. Ternary metal phosphides hold promise as efficient and low‐cost catalysts for neutral‐pH water splitting devices.
Sheets and paper: Ternary Ni0.1Co0.9P porous nanosheets anchored onto conductive carbon fiber paper, can be used as a bifunctional catalytic material for driving both water reduction and oxidation reactions efficiently in neutral‐pH electrolyte under ambient conditions.
Anorexia nervosa (AN) is a psychiatric illness with the highest mortality. Current treatment options have been limited to psychotherapy and nutritional support, with low efficacy and high relapse ...rates. Hypothalamic AgRP (agouti-related peptide) neurons that coexpress AGRP and neuropeptide Y (NPY) play a critical role in driving feeding while also modulating other complex behaviors. We have previously reported that genetic ablation of
, which encodes a member of the TET family dioxygenases, specifically in AgRP neurons in mice, activates these neurons and increases the expression of AGRP, NPY, and the vesicular GABA transporter (VGAT), leading to hyperphagia and anxiolytic effects. Bobcat339 is a synthetic small molecule predicted to bind to the catalytic pockets of TET proteins. Here, we report that Bobcat339 is effective in mitigating AN and anxiety/depressive-like behaviors using a well-established mouse model of activity-based anorexia (ABA). We show that treating mice with Bobcat339 decreases TET3 expression in AgRP neurons and activates these neurons leading to increased feeding, decreased compulsive running, and diminished lethality in the ABA model. Mechanistically, Bobcat339 induces TET3 protein degradation while simultaneously stimulating the expression of AGRP, NPY, and VGAT in a TET3-dependent manner both in mouse and human neuronal cells, demonstrating a conserved, previously unsuspected mode of action of Bobcat339. Our findings suggest that Bobcat339 may potentially be a therapeutic for anorexia nervosa and stress-related disorders.
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