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关键词： Voltage control   Batteries   Legged locomotion   Control systems   Buck converters   Discharges (electric)   Switches   Current sharing   differential converter   fail-safe operation   module shedding   series-parallel connected output   ultrawide voltage   voltage sharing  

摘要： In this article, a modular output series-parallel series resonant converter (SRC) differential buck converter is analyzed for high-power, ultra-wide-voltage applications such as battery formation systems and bench-type power supplies where a zero voltage discharging function is required. An independent control method in one module is proposed to increase the efficiency of the converter compared to the conventional complementary control method. In the modular output-series connection, higher efficiency can be achieved by shedding needless modules in the low voltage range. Module shedding and activating techniques are proposed to eliminate current and voltage transients during a mode change under any load condition without the use of additional bypass switches. In addition, when a fault occurs in one module, its effect on the other module is analyzed. A practical solution involving turn-off processes for fail-safe operation is proposed, which reduces current stress and voltage spikes on devices and effect among modules without depending on the external signal from the central controller and the communication delay. A prototype of a modular series-parallel SRC- differential buck converter is implemented to verify the proposed concept.

关键词： Differential distraction   external distraction   monobloc   syndromic craniofacial dysostosis  

摘要： Midface advancement at the monobloc level can be the seminal life event for patients with craniofacial dysostosis. Monobloc reconstruction, when planned appropriately, can simultaneously and definitively address multiple functional and aesthetic deficiencies in these patients. The application of distraction has reduced the morbidity experienced with traditional monobloc surgery. The purpose of this study is to report on the outcomes, stability, and growth in younger patients after monobloc advancement in syndromic craniosynostosis patients. The authors report a consecutive series of thirty patients with craniofacial dysostosis treated through monobloc differential distraction osteogenesis. Detailed history, photographic, and long-term radiographic data are reviewed, including a subset of patients who were skeletally immature at the time of their treatment. Differential distraction allows control of midface pitch, roll, and yaw, optimizing functional and aesthetic outcomes. There were no infectious complications requiring reoperation. The average surgical age for all patients was 12.5 years. For the 7 patients age <7 years, average age was 6 years. For all patients, the mean horizontal movement was 12 mm at nasion and 10 mm at A-point. At mean follow-up (4.8 years entire group and 6.2 years age <7 years group) a positive horizontal advancement of 1.1 mm at nasion and 0.8 mm at A-point was observed. More pronounced positive horizontal changes were seen in the age <7 years group. Monobloc differential distraction osteogenesis affords safe and precise repositioning of the midface. The advancement is skeletally stable and young patients show moderate continued growth.

关键词： Nitrogen doping   Graphene nanoflakes   Calorimetry   DSC   Combustion heat   Carbon nanomaterials  

摘要： Nitrogen-doped graphene nanoflakes (NGNFs) with variable N-doping level of 5.0-10.7 at.% were produced by chemical vapor deposition from different CH3CN/C6H6 mixtures. NGNFs were characterized by transmission electron microscopy, low-temperature nitrogen physisorption, X-ray photoelectron and Raman spectroscopies. Their combustion heats were measured by differential scanning calorimetry in the temperature range of 303-1273 K and showed a bell-shaped dependence on the nitrogen content with a maximum of 30.1 +/- 1.0 kJ g(-1) at a nitrogen level of 7.8 at.%. The contributions of the pi-pi stacking, resonance and surface/edge energies to the combustion heat were discussed. The approach for estimation of the combustion heat of NGNFs assuming the contributions from pyridinic, pyrrolic and graphitic nitrogen species was proposed for the first time.

关键词： graphene resonant   biaxial accelerometer   finite element simulation   differential mode  

摘要： In this paper, a novel two-axis differential resonant accelerometer based on graphene with transmission beams is presented. This accelerometer can not only reduce the cross sensitivity, but also overcome the influence of gravity, realizing fast and accurate measurement of the direction and magnitude of acceleration on the horizontal plane. The simulation results show that the critical buckling acceleration is 460 g, the linear range is 0-89 g, while the differential sensitivity is 50,919 Hz/g, which is generally higher than that of the resonant accelerometer reported previously. Thus, the accelerometer belongs to the ultra-high sensitivity accelerometer. In addition, increasing the length and tension of graphene can obviously increase the critical linear acceleration and critical buckling acceleration with the decreasing sensitivity of the accelerometer. Additionally, the size change of the force transfer structure can significantly affect the detection performance. As the etching accuracy reaches the order of 100 nm, the critical buckling acceleration can reach up to 5 x 10(4) g, with a sensitivity of 250 Hz/g. To sum up, a feasible design of a biaxial graphene resonant accelerometer is proposed in this work, which provides a theoretical reference for the fabrication of a graphene accelerometer with high precision and stability.

关键词： 积分-高等学校-教材-数学分析-高等学校-教材-微分-高等学校-教材  

ISBN: (纸本)9787030705839

摘要： 本书主要研究数学分析中的微分与积分及相关的一些问题。内容包括一元函数微分学、一元函数微分法的应用、一元函数积分学和多元函数及其微分学等。书中主要通过一些疑难解析和大量的典型例题来解析数学分析的内容和解题方法，并提供了一定数量的进阶练习题。

关键词： ACPA = anti‐cyclic citrullinated peptide antibodies   ACR = American college of rheumatology   ACTB = actin beta   BMI = body mass index   CRP = C-reactive protein   CV = cardiovascular   DAPSA = disease activity in psoriatic arthritis   DAS28 = disease activity score 28   DMARDs = disease-modifying anti-rheumatic drugs   ESR = erythrocyte sedimentation rate   EULAR = European league against rheumatism   HAQ = health assessment questionnaire   HC = healthy controls   HDL = high density lipoprotein   HMW = high molecular weight   IGF = insulin-like growth factor   IL = interleukin   LDL = low density lipoprotein   LMW = low molecular weight   MAPK = mitogen-activated protein kinase   miRNA = microRNA   MMW = medium molecular weight   NF‐κB = nuclear factor κB   NSAIDs = non-steroidal anti-inflammatory drugs   OA = osteoarthritis   PASI = psoriasis area severity index   PBMCs = peripheral blood mononuclear cells   PsA = psoriatic arthritis   RA = rheumatoid arthritis   RF = rheumatoid factor   SIRT‐1 = silencing the gene for sirtuin   SNORD-25 = small nucleolar RNA = C/D Box 25   TGF-β = activity and in transforming growth factor   TNF = tumor necrosis factor   VAS = visual analogue scale   VEGF = vascular endothelial growth factor  

摘要： The differential diagnosis of psoriatic arthritis (PsA) and rheumatoid arthritis (RA) is difficult because of the lack of diagnostic clinical signs and reliable biomarkers. This study investigated microRNAs (miRNA) and adipokines as potential additional markers to discriminate PsA from RA. The expression profile of miRNA (miR-21, miR140, miR-146a, miR-155, miR-181b, miR-223, miR-let-7e) and inflammatory cytokines (IL-1 beta, IL-6, IL-17a, IL-23a, TNF-a) from peripheral blood mononuclear cells of PsA and RA patients compared to healthy controls (HC) were evaluated by real-time PCR, and serum adipokines (adiponectin, chemerin, leptin, resistin, visfatin) and cytokines by ELISA assay. Univariable binary logistic regression was used to find the association between PsA and potential predictors. The gene expression of miRNA and cytokines and the serum levels of adipokines were found significantly different in PsA and RA patients compared to HC, as well as in PsA versus RA. MiR-140 gene expression resulted up-regulated in PsA patients and reduced in RA in comparison to HC, and, for the first time, significantly higher in PsA compared with RA. Serum levels of IL-23a and leptin were significantly increased in PsA and RA populations than in HC, as well as in PsA versus RA. Furthermore, circulating TNF-a was up-regulated in PsA and RA in comparison to controls, while resulted higher in RA than in PsA. Univariable binary logistic regression analysis found the above-mentioned markers associated to PsA versus RA. Our results first demonstrated an increased expression of circulating miR-140 and serum leptin in PsA patients compared to RA, which were identified as potential additional biomarkers to discriminate PsA from RA. Since the differential diagnosis of PsA and RA poses challenges in clinical practice, our data may help to enhance the diagnostic performance of PsA in daily practice. (Translational Research 2022;239:18-34)

关键词： volatile organic compounds   differential ion mobility spectrometry   ion mobility spectrometry  

摘要： The article presents a technique of differential ion mobility spectrometry (DMS) applicable to the detection and identification of volatile organic compounds (VOCs) from such categories as n-alkanes, alcohols, acetate esters, ketones, botulinum toxin, BTX, and fluoro- and chloro-organic compounds. A possibility of mixture identification using only the DMS spectrometer is analyzed, and several examples are published for the first time. An analysis of different compounds and their mechanisms of fragmentation, influence on effective ion temperature, and high electric field intensity is discussed.

关键词： Triple-negative breast carcinoma   Adenoid cystic carcinoma   Adenomyoepithelioma   Acinic cell carcinoma   Mucoepidermoid carcinoma   Tall cell carcinoma with reverse polarity   Secretory carcinoma  

摘要： Triple-negative breast carcinomas constitute a wide spectrum of lesions, mostly being highly aggressive. Nevertheless, some special histologic subtypes can have low malignant potential. The purpose of the present paper is to review diagnostic criteria and prognostic parameters of breast neoplasms of special histotypes. Specifically, adenoid cystic carcinoma, adenomyoepithelioma, acinic cell carcinoma, mucoepidermoid carcinoma, tall cell carcinoma with reverse polarity, and secretory carcinoma will be discussed. For each tumour, definition and morphological and molecular features, together with prognostic parameters, will be presented. Paradigmatic cases will be illustrated.

关键词： Neurology   Psychopharmacology   Pharmacotherapy   Neurosciences   Psychiatry  

摘要： Pediatric-onset multiple sclerosis (POMS) is a rare neuroinflammatory and neurodegenerative disease that has a significant impact on long-term physical and cognitive patient outcomes. A small percentage of multiple sclerosis (MS) diagnoses occur before the age of 18 years. Before treatment initiation, a careful differential diagnosis and exclusion of other similar acquired demyelinating syndromes such as anti-aquaporin-4-associated neuromyelitis optica spectrum disorder (AQP4-NMOSD) and myelin oligodendrocyte glycoprotein antibody spectrum disorder (MOGSD) is warranted. The recent 2017 changes to the McDonald criteria can successfully predict up to 71% of MS diagnoses and have good specificity of 95% and sensitivity of 71%. Additional measures such as the presence of T1-weighted hypointense lesions and/or contrast-enhancing lesions significantly increase the accuracy of diagnosis. In adults, early use of disease-modifying therapies (DMTs) is instrumental to a better long-term prognosis, including lower rates of relapse and disability worsening, and numerous FDA-approved therapies for adult-onset MS are available. However, unlike their adult counterparts, the development, testing, and regulatory approval of POMS treatments have been significantly slower and hindered by logistic and/or ethical considerations. Currently, only two MS DMTs (fingolimod and teriflunomide) have been tested in large phase III trials and approved by regulatory agencies for use in POMS. First-line therapies not approved by the FDA for use in children (interferon-beta and glatiramer acetate) are also commonly used and result in a significant reduction in inflammatory activity when compared with non-treated POMS patients. An increasing number of POMS patients are now treated with moderate efficacy therapies such as dimethyl fumarate and high-efficacy therapies such as natalizumab, anti-CD20 monoclonal antibodies, anti-CD52 monoclonal antibodies, and/or autologous hematopoietic stem cell transpla

关键词： External Ventricular Drainage   Pneumocephalus   Intraventricular Haemorrhage   Neurocritical Care  

摘要： External ventricular drainage (EVD) is carried out in many neurosurgical conditions for the diversion of cerebrospinal fluid. These EVD systems can, however, malfunction with potentially lethal consequences. Air bubbles within the EVD can result in air locking of the system with subsequent blockage of drainage, with blood clots and debris being the other causes. There are both non-invasive and invasive methods of rectifying such blockages, with invasive procedures having its associated risks. This is especially so for EVD revisions, with each surgery increasing the risk of ventriculitis. We describe a case of bilateral air locked EVD managed successfully with a novel non-invasive 'pressure differential efflux technique'. This method exploits the pressure gradient established by adjusting each EVD to a different height to evacuate the pneumoventricle. In addition, we present a sequential approach to the management of EVD malfunction, based on the current literature and our institutional protocol. (c) 2021 Elsevier Ltd. All rights reserved.