Synaptic Neurotransmission Depression in Ventral Tegmental Dopamine Neurons and Cannabinoid-Associated Addictive Learning

Drug addiction is an association of compulsive drug use with long-term associative learning/memory. Multiple forms of learning/memory are primarily subserved by activity- or experience-dependent synaptic long-term potentiation (LTP) and long-term depression (LTD). Recent studies suggest LTP expression in locally activated glutamate synapses onto dopamine neurons (local Glu-DA synapses) of the midbrain ventral tegmental area (VTA) following a single or chronic exposure to many drugs of abuse, whereas a single exposure to cannabinoid did not significantly affect synaptic plasticity at these synapses. It is unknown whether chronic exposure of cannabis (marijuana or cannabinoids), the most commonly used illicit drug worldwide, induce LTP or LTD at these synapses. More importantly, whether such alterations in VTA synaptic plasticity causatively contribute to drug addictive behavior has not previously been addressed. Here we show in rats that chronic cannabinoid exposure activates VTA cannabinoid CB1 receptors to induce transient neurotransmission depression at VTA local Glu-DA synapses through activation of NMDA receptors and subsequent endocytosis of AMPA receptor GluR2 subunits. A GluR2-derived peptide blocks cannabinoid-induced VTA synaptic depression and conditioned place preference, i.e., learning to associate drug exposure with environmental cues. These data not only provide the first evidence, to our knowledge, that NMDA receptor-dependent synaptic depression at VTA dopamine circuitry requires GluR2 endocytosis, but also suggest an essential contribution of such synaptic depression to cannabinoid-associated addictive learning, in addition to pointing to novel pharmacological strategies for the treatment of cannabis addiction

Synthesis of Nickel Cobaltite/Multiwalled Carbon Nanotubes Composites and Their Application for Removing Uranium (VI)

A facile hydrothermal method has been developed to prepare a nickel cobaltite/multiwalled carbon nanotubes (NiCo2O4/MWCNTs) composite. The structure and morphology of NiCo2O4/MWCNTs were tested by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscope, and nitrogen sorption isotherm. The nitrogen sorption isotherms of the NiCo2O4/MWCNTs composite indicate that NiCo2O4/MWCNT is a typical mesoporous material. The average pore width of NiCo2O4/MWCNTs is 10.0 nm. When serving as the adsorbent for uranium, the NiCo2O4/MWCNTs composite exhibits a high adsorption capacity, suggesting their potential use in water treatment. The influences of pH, temperature, and time on the adsorption efficiency of uranium by NiCo2O4/MWCNTs were studied. The experimental results show that the maximum adsorption capacity of NiCo2O4/MWCNTs for uranium(VI) is 247.4 mg g−1, suggesting that it is an effective uranium(VI) sorbent in water treatment. Thermodynamic analysis results show that the process is endothermic in nature. As the adsorption capacity does not increase significantly with the increase in T, the uranium adsorption by NiCo2O4/MWCNTs can be carried out at room temperature to reduce energy consumption. The NiCo2O4/MWCNTs composite can be a good alternative to remove uranium(VI)

A Review on the Policy, Technology and Evaluation Method of Low-Carbon Buildings and Communities

In order to address global warming, most countries in the world have established carbon neutral targets and are continuously taking action to achieve carbon neutrality. The building sector accounts for 36% of end-use energy consumption and 37% of energy-related CO2 emissions globally, so carbon mitigation in building sector is considered to be the most critical step in completing the “last mile” of global carbon neutrality. Low-carbon buildings and communities are the foundation for achieving low-carbon cities and the key transition to reach the goal of carbon neutrality. Therefore, this review aimed to: (a) provide a comprehensive review of countries’ policies on low-carbon buildings and communities and a theoretical basis for improving the corresponding laws and regulations; (b) investigate low-carbon technologies related to building and community construction and operation, as well as identify the current technology gaps; (c) provide a comprehensive overview of low-carbon buildings and communities assessment systems to analyze and evaluate the economic, technical, environmental and social benefits of current building and community energy systems; and (d) identify enablers and barriers in low-carbon buildings and communities to provide direction for future research. The results of this paper can provide comprehensive insights in to further achieving low-carbon buildings and communities

A Review on the Policy, Technology and Evaluation Method of Low-Carbon Buildings and Communities

In order to address global warming, most countries in the world have established carbon neutral targets and are continuously taking action to achieve carbon neutrality. The building sector accounts for 36% of end-use energy consumption and 37% of energy-related CO2 emissions globally, so carbon mitigation in building sector is considered to be the most critical step in completing the “last mile” of global carbon neutrality. Low-carbon buildings and communities are the foundation for achieving low-carbon cities and the key transition to reach the goal of carbon neutrality. Therefore, this review aimed to: (a) provide a comprehensive review of countries’ policies on low-carbon buildings and communities and a theoretical basis for improving the corresponding laws and regulations; (b) investigate low-carbon technologies related to building and community construction and operation, as well as identify the current technology gaps; (c) provide a comprehensive overview of low-carbon buildings and communities assessment systems to analyze and evaluate the economic, technical, environmental and social benefits of current building and community energy systems; and (d) identify enablers and barriers in low-carbon buildings and communities to provide direction for future research. The results of this paper can provide comprehensive insights in to further achieving low-carbon buildings and communities

Evaluation and Optimization of heat Pump Combined District Heating System: A Case Study of China

The district heating area in China is continuously increasing, which brings an increase in district heating load. In order to solve the shortage of heating power and realize the carbon neutral target, this study proposes two retrofit schemes for district heating system by integrating air source heat pump and water source heat pump, respectively. Mathematical models are established to study the performance of the integrated systems and a bilevel optimization model is proposed to optimize them. The results show that the air source heat pump combined district heating system has better performance compared to the conventional system, which reduces 50% energy consumption, 10.8% carbon emissions and achieves better economy. The dynamic coupling property of the district heating network and power grid are also considered, and the results indicate that the introduction of air source heat pump can effectively improve the efficiency and stability of power grid and reduce the seasonal fluctuation. The potential of large-scale application of air source heat pump combined system in Beijing is evaluated. The results reveal that retrofit scheme of integrating air source heat pumps into district heating system can cover 2930 MW heating load and bring 362 million Chinese Yuan profit by reducing 219,000 tons of carbon emissions and 539,000 tons of standard coal consumption in 2025

Evaluation and Optimization of heat Pump Combined District Heating System: A Case Study of China

The district heating area in China is continuously increasing, which brings an increase in district heating load. In order to solve the shortage of heating power and realize the carbon neutral target, this study proposes two retrofit schemes for district heating system by integrating air source heat pump and water source heat pump, respectively. Mathematical models are established to study the performance of the integrated systems and a bilevel optimization model is proposed to optimize them. The results show that the air source heat pump combined district heating system has better performance compared to the conventional system, which reduces 50% energy consumption, 10.8% carbon emissions and achieves better economy. The dynamic coupling property of the district heating network and power grid are also considered, and the results indicate that the introduction of air source heat pump can effectively improve the efficiency and stability of power grid and reduce the seasonal fluctuation. The potential of large-scale application of air source heat pump combined system in Beijing is evaluated. The results reveal that retrofit scheme of integrating air source heat pumps into district heating system can cover 2930 MW heating load and bring 362 million Chinese Yuan profit by reducing 219,000 tons of carbon emissions and 539,000 tons of standard coal consumption in 2025

VTA CB1R mediates cannabinoid-facilitated LTD induction in the VTA.

<p>(A) Systemic pretreatment with the selective CB1R antagonist AM281 prior to daily HU210 injection blocked LFS-induced LTD in the VTA. (B) Localization of bilaterally microfusioned adenoviral vectors containing GFP into the VTA. Scale bar: 150 µm. (C) Graph (top) and immunoblotting (bottom photos) show that CB1R shRNA (shRNA), but not its scrambled sequence (Scrm), reduced CB1R expression in the VTA 2 and 5 days after intra-VTA injection. One-way ANOVA: <i>F</i>_3,8 = 11.949, <i>p</i><0.01. * <i>p</i><0.05, ** <i>p</i><0.01 versus vehicle (LSD post hoc test). (D) Relative to scrambled shRNA (Scrm), CB1R shRNA (shRNA) infusion into the VTA inhibited LFS-induced LTD in HU210-treated rats. (E) Summary of LTD induction following treatment with saline, AM281, scrambled shRNA (Scrm) or CB1R shRNA (shRNA). One-way ANOVA: <i>F</i>_7,70 = 14.853, <i>p</i><0.001. * <i>p</i><0.01, ** <i>p</i><0.001 (LSD post hoc test) versus baseline or between Scrm+HU210 and siRNA+HU210.</p

Blockade of HU210-elicited CPP by TAT-GluR2 peptide.

<p>(A) Systemic injection of TAT-GluR2 peptide, but not its scrambled version (sTAT-GluR2), blocked the acquisition, but not the expression (ex), of HU210-elicited CPP. One-way ANOVA: <i>F</i>_9,72 = 3.132, <i>p</i><0.01. * <i>p</i><0.01 versus pre-test. (B) Diffusion of the fluorescent dansyl-TAT-GluR2 in the VTA after intra-VTA injection. Diagram (left) illustrates the diffusion area shown in the fluorescent image (middle). The right photograph shows peptide transduction in individual VTA neurons. ml, medial lemniscus. Scale bars: 400 µm (middle) or 25 µm (right). (C) Bilateral intra-VTA injection of TAT-GluR2 (<i>n</i> = 9), but not scrambled peptide (sTAT-GluR2; <i>n</i> = 9), blocked HU210-elicited CPP (left graph). * <i>p</i><0.05 versus pre-test. The right histograms show reconstructions of histology sections illustrating VTA injection sites. (D) Effects of various treatments on locomotor activity. Animals receiving various treatments did not show significant difference in locomotor activity on the testing day, i.e. the total distance traveled in all 3 compartments (one-way ANOVA, <i>F</i>_5,43 = 1.000, <i>p</i> = 0.430) and total entry times to each compartment (one-way ANOVA, <i>F</i>_5,43 = 0.164, <i>p</i> = 0.975).</p

Cannabinoids facilitate LTD induction in the VTA.

<p>(A) HFS failed to induce LTP in naïve rat VTA. (B) LFS failed to induce LTD in naïve rat VTA. (C) HFS failed to induce LTP from the VTA of HU210-treated rats. (D) LFS induced LTD from the VTA of chronic HU210-treated rats. (E) LFS induced LTD from the VTA of chronic THC-treated rats. (F) Summary of LTD induction under various conditions. * <i>p</i><0.01 versus baseline.</p