Nonsmooth dynamic tracking control for nonlinear systems with mismatched disturbances: Algorithm and practice

This article addresses a dynamic tracking control issue for a class of nonlinear systems subject to mismatched disturbances. As an alternative control design algorithm for practitioners, a simple nonsmooth tracking scheme with a self-tuning scaling gain is proposed under a nonrecursive synthesis framework. In reference to the existing related works, a main distinguishable feature is that the scaling gain of the proposed regulation law can be adaptively adjusted subject to different perturbation levels; therefore, the control system is able to achieve an improved transient-time control performance while an accurate tracking objective is guaranteed. In addition, the proposed nonrecursive design philosophy is able to obtain the simplest state-feedback expression of the controller through essentially detaching the stability analysis with controller design procedure, i.e., without going through recursive determination steps of classical virtual controllers. The efficacy of the proposed method is validated by an illustrative numerical example and a real-life application to a dc-dc boost converter system

Early Jurassic metamorphism of the eastern segment of the Lhasa terrane in South Tibet and its tectonic significance

<p>The metamorphic belt in the Dongjiu area is located in the eastern segment of the Lhasa terrane in South Tibet. The Dongjiu metamorphic rocks are primarily composed of schist and gneiss, with minor amounts of marble, and the protoliths are sedimentary rocks with Precambrian and early Palaeozoic zircons probably deposited during the Palaeozoic or late Neoproterozoic. On the basis of petrology and phase equilibria modelling, this study shows that the Dongjiu metamorphic belt has experienced a kyanite-grade metamorphism, which is characterized by a decompressional vector with slight cooling from a peak of 9.6 kbar and 745°C to medium-pressure amphibolite-facies metamorphic overprinting at 5–6 kbar and 600–630°C. This <i>P–T</i> path was well recorded and recovered by garnet zoning profiles. Laser ablation inductively coupled plasma mass spectrometry <i>in situ</i> U–Pb analyses on metamorphic zircons and zircon rims yielded concordant ²⁰⁶Pb/²³⁸U ages of <i>c</i>. 194–192 Ma, suggesting that the Dongjiu metamorphic rocks were formed during the Early Jurassic. Therefore, the Dongjiu metamorphic belt, together with the western Nyainqentanglha, Basongco, and Zhala metamorphic belts, constitutes a nearly continuous tectonic unit with an E–W extension of at least 500 km between the northern and southern Lhasa terranes. The metamorphic ages of these belts, ranging from 230 to 192 Ma, show a younger trend from west to east, indicating that the central segment of the Lhasa terrane experienced an eastward asynchronous collisional orogeny during the Late Triassic to Early Jurassic.</p

DataSheet_1_Mendelian randomization analysis does not reveal a causal influence of mental diseases on osteoporosis.zip

IntroductionOsteoporosis (OP) is primarily diagnosed through bone mineral density (BMD) measurements, and it often leads to fracture. Observational studies suggest that several mental diseases (MDs) may be linked to OP, but the causal direction of these associations remain unclear. This study aims to explore the potential causal association between five MDs (Schizophrenia, Depression, Alzheimer's disease, Parkinson's disease, and Epilepsy) and the risk of OP.MethodsFirst, single-nucleotide polymorphisms (SNPs) were filtered from summary-level genome-wide association studies using quality control measures. Subsequently, we employed two-sample Mendelian randomization (MR) analysis to indirectly analyze the causal effect of MDs on the risk of OP through bone mineral density (in total body, femoral neck, lumbar spine, forearm, and heel) and fractures (in leg, arm, heel, spine, and osteoporotic fractures). Lastly, the causal effect of the MDs on the risk of OP was evaluated directly through OP. MR analysis was performed using several methods, including inverse variance weighting (IVW)-random effects, IVW-fixed effects, maximum likelihood, weighted median, MR-Egger regression, and penalized weighted median.ResultsThe results did not show any evidence of a causal relationship between MDs and the risk of OP (with almost all P values > 0.05). The robustness of the above results was proved to be good.DiscussionIn conclusion, this study did not find evidence supporting the claim that MDs have a definitive impact on the risk of OP, which contradicts many existing observational reports. Further studies are needed to determine the potential mechanisms of the associations observed in observational studies.</p

Additional file 1: of Effectiveness of transcutaneous electrical nerve stimulation for the treatment of migraine: a meta-analysis of randomized controlled trials

Search strategy. (DOCX 14 kb

DDQ-Catalyzed Direct C(sp³)–H Amination of Alkylheteroarenes: Synthesis of Biheteroarenes under Aerobic and Metal-Free Conditions

A strategy for oxidative Csp³–H/N–H cross-coupling is presented. This reaction successfully utilizes 2,3-dichloro-5,6-dicyano-<i>p</i>-benzoquinone (DDQ) and <i>tert</i>-butyl nitrite (TBN) as co-catalysts to construct the biomedical applicable biheteroarenes under aerobic conditions. Notably, this amination reaction is successful with a wide range of alkylheteroarenes and could be used as a functionalization tactic for pharmaceutical research and other areas. Furthermore, preliminary mechanistic studies indicate that the C–N bond formation proceeds through the nucleophilic attack of azole to the carbon cation

Metabolic Profiling Provides a System Understanding of Hypothyroidism in Rats and Its Application

<div><h3>Background</h3><p>Hypothyroidism is a chronic condition of endocrine disorder and its precise molecular mechanism remains obscure. In spite of certain efficacy of thyroid hormone replacement therapy in treating hypothyroidism, it often results in other side effects because of its over-replacement, so it is still urgent to discover new modes of treatment for hypothyroidism. <em>Sini</em> decoction (<em>SND</em>) is a well-known formula of Traditional Chinese Medicine (TCM) and is considered as efficient agents against hypothyroidism. However, its holistic effect assessment and mechanistic understanding are still lacking due to its complex components.</p> <h3>Methodology/Principal Findings</h3><p>A urinary metabonomic method based on ultra performance liquid chromatography coupled to mass spectrometry was employed to explore global metabolic characters of hypothyroidism. Three typical hypothyroidism models (methimazole-, propylthiouracil- and thyroidectomy-induced hypothyroidism) were applied to elucidate the molecular mechanism of hypothyroidism. 17, 21, 19 potential biomarkers were identified with these three hypothyroidism models respectively, primarily involved in energy metabolism, amino acid metabolism, sphingolipid metabolism and purine metabolism. In order to avert the interference of drug interaction between the antithyroid drugs and <em>SND</em>, the thyroidectomy-induced hypothyroidism model was further used to systematically assess the therapeutic efficacy of <em>SND</em> on hypothyroidism. A time-dependent recovery tendency was observed in <em>SND</em>-treated group from the beginning of model to the end of treatment, suggesting that <em>SND</em> exerted a recovery effect on hypothyroidism in a time-dependent manner through partially regulating the perturbed metabolic pathways.</p> <h3>Conclusions/Significance</h3><p>Our results showed that the metabonomic approach is instrumental to understand the pathophysiology of hypothyroidism and offers a valuable tool for systematically studying the therapeutic effects of <em>SND</em> on hypothyroidism.</p> </div

Comparison of different ions in urine of Sham group, Sham + <i>SND</i> group, Hypo group, Hypo + <i>SND</i> group and Hypo + T₄ group after 4-week treatment.

<p>* <i>p</i>-Value<0.05 compared to Sham group, ** <i>p</i>-Value< 0.01 compared to Sham group, *** <i>p</i>-Value<0.001 compared to Sham group; ^#<i>p</i>-Value<0.05 compared to Hypo group, ^##<i>p</i>-Value<0.01 compared to Hypo group, ^###<i>p</i>-Value<0.001 compared to Hypo group.</p

PLS-DA scores plot (top panel), loading plot (middle panel) and S-plot (bottom panel) of the UHPLC/TOF-MS spectral from control group (box) and hypothyroid group (dot).

<p>(<b>A</b>: control group <i>vs</i> MMI group; <b>B</b>: control group <i>vs</i> PTU group; <b>C</b>: control group <i>vs</i> thyroidectomy-induced hypothyroid group).</p

Identification of a selected marker (<i>m/z</i> 124.0082).

<p>(<b>A</b>) Extracted ion chromatogram (EIC) of m/z 124.0082 (t<i>_R</i> = 0.69 min); (<b>B</b>) MS/MS spectrum of the ion in the urine; (<b>C</b>) MS/MS spectrum of a commercial standard. The collision energy was 18 V.</p

PLS-DA scores plot to evaluate the therapeutical effects of SND.

<p>(<b>A</b>) PLS-DA scores plot derived from urine levels of 21 potential biomarkers in Sham group (dot), Sham + <i>SND</i> group (diamond), Hypo group (box), Hypo + <i>SND</i> group (inverted triangle) and Hypo + T₄ group (triangle). (<b>B</b>) A time-related trajectory of metabolite patterns from PLS-DA model classifying the state of rats at different time points: before surgery (dot), after surgery (box), treatment for two weeks (diamond), treatment for three weeks (triangle); treatment for four weeks (inverted triangle).</p