Obesity is considered as a chronic disease that can induce a series of comorbidities and complications. Chinese medicine has long clinical experiences in the treatment of obesity. This review ...summarizes the natural products from traditional Chinese medicine (TCM) that are reported to have anti‐obesity effects in the past two decades. Botanic TCM comprises 90% of total Chinese crude drugs, and generally contains various active ingredients, in which the effective anti‐obesity ingredients identified can be divided into saponins, polysaccharides, alkaloids, polyphenols and others. Astragaloside IV, glycyrrhizin, macrostemonoside A, berberine, betaine, capsaicin, matrine, methyl piperate, piperine, rutaecarpine, asimilobine, epigallocatechingallate, magnolol, resveratrol, soybean‐isoflavone, α‐linolenic acid, emodin, geniposide, phillyrin, salidroside and ursolic acid are specified in this review, and their sources, models, efficacy are described. It is concluded that the mechanisms of these components for the treatment of obesity include: (i) suppression of appetite, increase of satiety, reduction of energy intake; (ii) reduction in the digestion and absorption of exogenous lipid; (iii) attenuation of the synthesis of endogenous lipid; (iv) promotion of the oxidation and expenditure of lipid and (v) improvement of lipid metabolism disorder. Authors believe that the effective compounds from TCM will provide an alternative and hopeful way for the treatment of obesity.
Wide bandgap oxide semiconductors constitute a unique class of materials that combine properties of electrical conductivity and optical transparency. They are being widely used as key materials in ...optoelectronic device applications, including flat‐panel displays, solar cells, OLED, and emerging flexible and transparent electronics. In this article, an up‐to‐date review on both the fundamental understanding of materials physics of oxide semiconductors, and recent research progress on design of new materials and high‐performing thin film transistor (TFT) devices in the context of fundamental understanding is presented. In particular, an in depth overview is first provided on current understanding of the electronic structures, defect and doping chemistry, optical and transport properties of oxide semiconductors, which provide essential guiding principles for new material design and device optimization. With these principles, recent advances in design of p‐type oxide semiconductors, new approaches for achieving cost‐effective transparent (flexible) electrodes, and the creation of high mobility 2D electron gas (2DEG) at oxide surfaces and interfaces with a wealth of fascinating physical properties of great potential for novel device design are then reviewed. Finally, recent progress and perspective of oxide TFT based on new oxide semiconductors, 2DEG, and low‐temperature solution processed oxide semiconductor for flexible electronics will be reviewed.
Wide‐bandgap oxide semiconductors uniquely combine electrical conductivity and optical transparency and are widely used in optoelectronic devices. The materials physics of wide‐bandgap oxide semiconductors, the recent progress in the design of new materials and novel thin‐film transistor (TFT) devices, and current challenges and perspectives are reviewed.
Control of the radiative properties of functional molecules near metals is a key issue in nano-optics, and is particularly important in the fields of energy transfer and light manipulation at the ...nanoscale and the development of plasmonic devices. Despite the various vibronic transitions (S1 (vvariant prime) arrow right S0 (v)) available for frequency tuning of fluorescence, the molecular emissions near metals reported to date have been subject to Kasha's rule, with radiative decay from the lowest excited state (S1 (0)) (refs 6-10). Here, we show resonant hot electroluminescence arising directly from higher vibronic levels of the singlet excited state (S1 (vvariant prime > 0)) for porphyrin molecules confined inside a nanocavity in a scanning tunnelling microscope, by spectrally tuning the frequency of plasmons. We also demonstrate the generation of unexpected upconversion electroluminescence. These observations suggest that the local nanocavity plasmons behave like a strong coherent optical source with tunable energy, and can be used to actively control the radiative channels of molecular emitters by means of intense resonance enhancement of both excitation and emission.
The blood–brain barrier (BBB) is an evolutionarily conserved, structural, and functional separation between circulating blood and the central nervous system (CNS). By controlling permeability into ...and out of the nervous system, the BBB has a critical role in the precise regulation of neural processes. Here, we review recent studies demonstrating that permeability at the BBB is dynamically controlled by circadian rhythms and sleep. An endogenous circadian rhythm in the BBB controls transporter function, regulating permeability across the BBB. In addition, sleep promotes the clearance of metabolites along the BBB, as well as endocytosis across the BBB. Finally, we highlight the implications of this regulation for diseases, including epilepsy.
Recent evidence from fly models reveals an endogenous circadian rhythm at the BBB. This rhythm controls function of the permeability-glycoprotein multidrug transporter, which actively pumps both endogenous and exogenous molecules out of the CNS. Function of this transporter is decreased at night, increasing permeability to multiple substrates into the brain overnight.Endocytosis is a newly appreciated important function for sleep. Endocytosis across the BBB is increased during sleep and, when inhibited, increases the need for sleep.Sleep also promotes the clearance of metabolites out of the brain along paravascular spaces. During sleep, the interstitial spaces of the brain are larger, allowing for more robust movement of metabolites from interstitial spaces into the CSF. These solutes can then travel along vessels and out of the brain.
Background
The aim of this study was to investigate the prevalence of epidemiologic and physician‐diagnosed pollen‐induced AR (PiAR) in the grasslands of northern China and to study the impact of the ...intensity and time of pollen exposure on PiAR prevalence.
Methods
A multistage, clustered and proportionately stratified random sampling with a field interviewer‐administered survey study was performed together with skin prick tests (SPT) and measurements of the daily pollen count.
Results
A total of 6043 subjects completed the study, with a proportion of 32.4% epidemiologic AR and 18.5% PiAR. The prevalence was higher in males than females (19.6% vs 17.4%, P = .024), but no difference between the two major residential and ethnic groups (Han and Mongolian) was observed. Subjects from urban areas showed higher prevalence of PiAR than rural areas (23.1% vs 14.0%, P < .001). Most PiAR patients were sensitized to two or more pollens (79.4%) with artemisia, chenopodium, and humulus scandens being the most common pollen types, which were similarly found as the top three sensitizing pollen allergens by SPT. There were significant regional differences in the prevalence of epidemiologic AR (from 18.6% to 52.9%) and PiAR (from 10.5% to 31.4%) among the six areas investigated. PiAR symptoms were positively associated with pollen counts, temperature, and precipitation (P < .05), but negatively with wind speed and pressure P < .05).
Conclusion
Pollen‐induced AR (PiAR) prevalence in the investigated region is extremely high due to high seasonal pollen exposure, which was influenced by local environmental and climate conditions.
Abstract Peripheral neuropathy is a common and major complication of diabetes, the underlying mechanisms of which are not fully understood. Using a mouse model of type II diabetes, the present study ...investigated the role of phosphodiesterase-5 (PDE5) in peripheral neuropathy. BKS.Cg-m+/+Leprdb/J (db/db) mice were treated with sildenafil, a specific inhibitor of PDE5, at doses of 2 and 10 mg/kg or saline. Levels of PDE5 and morphometric parameters in sciatic nerve tissue as well as the motor and sensory function were measured in these mice. In diabetic mice, PDE5 expression in sciatic nerve tissue was significantly upregulated, whereas the myelin sheath thickness, myelin basic protein (MBP), and subcutaneous nerve fibers were significantly reduced. Treatment with sildenafil significantly improved neurological function, assayed by motor and sensory conducting velocities and thermal and mechanical noxious stimuli, concomitantly with increases in myelin sheath thickness, MBP levels, and subcutaneous nerve fibers. In vitro , hyperglycemia upregulated PDE5 in Schwann cells and reduced Schwann cell proliferation, migration, and expression of brain-derived neurotrophic factor (BDNF). Blockage of PDE5 with sildenafil increased cyclic guanosine monophosphate (cGMP) and completely abolished the effect of hyperglycemia on Schwann cells. Sildenafil upregulated cGMP-dependent protein kinase G I (PKGI), whereas inhibition of PKGI with a PKG inhibitor, KT5823, suppressed the inhibitory effect of sildenafil on Schwann cells. These data indicate that hyperglycemia substantially upregulates PDE5 expression and that the cGMP/PKG signaling pathway activated by sildenafil mediates the beneficial effects of sildenafil on diabetic peripheral neuropathy.
We present X-ray timing results of the new black hole candidate MAXI J1535−571 during its 2017 outburst from Hard X-ray Modulation Telescope (Insight-HXMT) observations taken from 2017 September 6 to ...23. Following the definitions given by Belloni, we find that the source exhibits transitions from the low/hard state to the hard intermediate state, and eventually to the soft intermediate state. Quasi-periodic oscillations (QPOs) are found in the intermediate states, which suggest different types of QPOs. With the large effective area of Insight-HXMT at high energies, we are able to present the energy dependence of the QPO amplitude and centroid frequency up to 100 keV, which has rarely been explored by previous satellites. We also find that the phase lag at the type-C QPOs centroid frequency is negative (soft lag) and strongly correlated with the centroid frequency. Assuming a geometrical origin of type-C QPOs, the source is consistent with being a high-inclination system.
In a semiconductor heterostructure, the Coulomb interaction is responsible for the electric current drag between two 2D electron gases across an electron impenetrable insulator. For two metallic ...layers separated by a ferromagnetic insulator (FI) layer, the electric current drag can be mediated by a nonequilibrium magnon current of the FI. We determine the drag current by using the semiclassical Boltzmann approach with proper boundary conditions of electrons and magnons at the metal-FI interface.
The global ionospheric maps (GIMs) produced by JPL are used to investigate the longitudinal structure of the low latitude ionosphere. As a proxy of the ionization parameter at low latitudes, the ...latitudinally integrated total electron content (ITEC) is first extracted from low latitude GIMs and then Fourier filtered to obtain the wavenumber‐4 components. We then study in detail the diurnal, seasonal and solar cycle variations of the wave patterns. It is found that the wavenumber‐4 patterns are intense and well developed in boreal summer and early boreal autumn, but quite weak in boreal winter. This seasonal variation is consistent with that of the zonal wind of the non‐migrating tide mode DE3. We also found that the wavenumber‐4 patterns shift eastward with a shifting speed that is smaller in daytime than at night. This is attributed to the contribution of both the eastward propagation of DE3 in E‐region and the zonal E ×B ion drifts in F‐region. Our results support the suggestion that the longitudinal wavenumber‐4 structure of the low latitude ionosphere should be originated from the non‐migrating tide mode DE3.
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