CHALLENGES OF DYNAMIC SIMULATION OF HIGH-SPEED ELECTROMAGNETIC VALVES OF GAS DISTRIBUTION DEVICES

High-speed electromagnetic valves of gas distribution devices are used in modern missile and space technology as jet micro-motors of the executive elements of missile stabilization systems, as well as to control the movement of spacecrafts in space. The problem of creating such valves which are simple and reliable in the operation is relevant. In this work, it is proposed at the development and design stage to perform computer modelling of mutually coupled electromechanical processes, such as: distribution of transient electromagnetic field, transients in an electric circuit, and movement of an electromagnet armature. Besides, the calculation of the force with which the compressed gas acts on the corresponding structural elements of the valve is proposed to be performed by solving the system of Navier-Stokes equations. All problems are solved by numerical methods in axisymmetrical formulation with the corresponding initial and boundary conditions. Improvement of the accuracy of electromagnetic calculations and taking into account the movement of the armature of an electromagnet in the process of multiphysics numerical simulation is achieved using so-called tunable elastic meshes. The paper presents a comparative analysis of the numerical results obtained for several designs of electromagnets. The features of the dynamics of high-speed electromagnets of gas distribution valves during on and off operations are analyzed, the corresponding dynamic characteristics calculated using the proposed technique are presented. Быстродействующие электромагнитные клапаны газораспределительных устройств применяются в современной ракетно-космической технике в качестве реактивных микродвигателей исполнительных органов систем стабилизации ракет, а также для управления движением космическими летательными аппаратами в пространстве. Проблема создания простых в эксплуатации и надежных в работе указанных клапанов является актуальной. В настоящей работе предлагается на стадии разработки и проектирования выполнять компьютерное моделирование взаимосвязанных электромеханических процессов, таких как: распределение нестационарного электромагнитного поля, переходные процессы в электрической цепи, движение якоря электромагнита. При этом расчет силы, с которой сжатый газ действует на соответствующие конструктивные элементы клапана, предлагается выполнять путем решения системы уравнений Навье-Стокса. Все задачи решаются численными методами в осесимметричной постановке с соответствующими начальными и граничными условиями. Повышение точности электромагнитных расчетов и учет движения якоря электромагнита в процессе мультифизического численного моделирования достигается благодаря использованию так называемых перестраиваемых упругих сеток. В работе приведен сравнительный анализ численных результатов, полученных для нескольких конструкций электромагнитов. Проанализированы особенности динамики быстродействующих электромагнитов газораспределительных клапанов при выполнении операций включения и отключения, приведены соответствующие динамические характеристики, рассчитанные по предложенной методике.

Автоматизація дослідження мультиварок

The multicooker design, structure and purpose of its main parts, the electrical circuit and the control system which includes sensor elements (sensors of pressure and temperature) are considered. The control unit in it is executed on the basis of 8-bit microcontroller MN15G1601 from PANASONIC SEMICONDUCTOR. The microcontroller read out a state of buttons of the keypad on the control panel and under the given program controls operation of multicooker and its elements.  The structural diagram for automation of researches and tests of multicooker is offered. The choice of the basic microcontroller and circuit components is carried out. The structural diagram includes the following elements: object of research - multicooker with support of functions of different modes of cooking under pressure; the sensors D1 - D4 (pressure, temperature of the bottom and walls of a bowl of multicooker and pressure in the middle of the devices); the normalizing amplifiers P1- P4; the four-channel switchboard of analog signals of type КР590КИ6; the analog-digital converter (АDC) of type К1113ПВ1; the microcontroller 1816ВЕ51 (МК51) containing built-in clock generator, storage of commands and data, built-in 4 ports and a serial communication channel; comparators K1- K4 of type К554СА3, which outputs combine on "OR" with output signals from microcontroller port; communicating devices with object ПЗО1– ПЗО4 which, through the actuators of the power device, interact with the object of research and set the mode of its research or testing. Through serial interface RS232C the circuit is connected with a personal computer which can change modes of researches or tests, and also to accept, save, reflect and document results of researches or tests. The developed circuit and algorithm of its operation allow to automate technological process of researches of operation modes of multicookers, to reduce duration of their carrying out, to raise accuracy of measurements, and to lower their cost.Рассмотрена конструкция мультиварки, устройство и назначение ее основных элементов, электрическая схема и система управления, которая включает сенсорные элементы (датчики давления и температуры). Блок управления в ней выполненный на базе 8-битового микроконтроллера MN15G1601 фирмы PANASONIC SEMICONDUCTOR. Микроконтроллер считывает состояние кнопок клавиатуры на панеле управления и по заданной программе управляет работой мультиварки и ее элементами. Предложена структурная схема для автоматизации исследований и испытаний мультиварок. Проведено выбор базового микроконтроллера и элементов схемы. Структурная схема включает следующие элементы: объект исследования – мультиварка з поддержкой функций разных режимов приготовления пищи под давлением; датчики Д1 – Д4 (напряжения, температуры днища и стенок чаши мультиварки и давления в средине устройства); нормирующие усилители П1 – П4; четырёхканальный коммутатор аналоговых сигналов типа КР590КИ6; аналого-цифровой преобразователь (АЦП) типа К1113ПВ1; микроконтроллер 1816ВЕ51 (МК51), содержащий встроенный генератор тактовых сигналов, память команд, ОЗУ, встроенные 4 порта і последовательный канал связи; компараторы К1 – К4 типа К554СА3, выходы которых объединены по «ИЛИ» с выходными сигналами с порта микроконтроллера; устройств связи с объектом ПЗО1 – ПЗО4, которые через исполнительные устройства силовой установки взаимодействуют с объектом исследований и задают режим его исследований или испытаний. Через последовательный интерфейс RS232С схема соединена з ПЭОМ, которая может изменять режимы исследований или испытаний, а также принимать, сохранять, отражать и документировать результаты исследований или испытаний. Разработанная схема и алгоритм её работы позволяют автоматизировать технологический процесс исследования режимов работы мультиварок, сократить сроки их проведения, повысить точность измерений, и снизить их стоимость.Розглянуто конструкцію мультиварки, устрій і призначення її основних елементів, електричну схему та систему керування, яка включає сенсорні елементи (датчики тиску і температури). Блок керування виконаний на базі спеціалізованого 8-бітового мікроконтролера MN15G1601 фірми PANASONIC SEMICONDUCTOR. Мікроконтролер зчитує стан кнопок клавіатури на панелі керування і по заданій програмі керує роботою мультиварки та її елементами. Запропонована структурна схема для автоматизації досліджень і випробувань мультиварок. Проведено вибір базового мікроконтролера та елементів схеми. Структурна схема включає наступні елементи: об’єкт досліджень – мультиварка з підтримкою функцій різних режимів приготування їжі під тиском; датчики Д1 – Д4 (напруги, температури дна і стінок чаші мультиварки та тиску всередині приладу); нормуючі підсилювачі П1 – П4; чотириканальний комутатор аналогових сигналів типу КР590КИ6; аналого – цифровий перетворювач (АЦП) типу К1113ПВ1; мікроконтролер 1816ВЕ51 (МК51), що містить вбудований генератор тактових сигналів, пам’ять команд, ОЗП, вбудовані 4 порти і послідовний канал зв’язку; компаратори К1 – К4 типу К554СА3, виходи яких за «АБО» об’єднані з вихідними сигналами з порту мікроконтролера; пристрої зв’язку з об’єктом ПЗО1 – ПЗО4, які через виконавчі пристрої силової установки взаємодіють з об’єктом досліджень і задають режим його випробувань або досліджень. Через послідовний інтерфейс RS232С схема з’єднана з ПЕОМ, яка може змінювати режими випробувань або досліджень, а також приймати, запам’ятовувати, відображати і документувати результати досліджень. Розроблена схема і алгоритм її роботи дозволяють автоматизувати технологічний процес дослідження режимів роботи мультиварок, скоротити терміни їх проведення, підвищити точність вимірювань та знизити їх вартість

Стан і перспективи мультифізичного моделювання індукційних кухонних плит

Induction cookers are a relatively new class of modern electrical household appliances – kitchen electric stoves that heat metal dishes with eddy currents generated by an electromagnetic field with a frequency of 20-100 kHz. Of considerable interest is the study of multiphysical (electromagnetic, thermal, and mechanical) processes occurring in induction cookers during their operation, as well as the development of methods for calculating and designing their structural elements. The results obtained should be intended for use in the practice of designing domestic induction cookers, as well as in the educational process for training specialists in the relevant curriculum. The number of published papers devoted to computer simulation of processes in induction cookers is many orders of magnitude less than the number of publications on the issues of well-developed numerical analysis of multiphysical phenomena in industrial induction heaters. The paper presents a review and analysis of publications, mainly published abroad devoted to multiphysical computer modeling of electromagnetic and thermal processes and phenomena in induction cookers and heated dishes. The directions for further research have been proposed: it is advisable to take into account, when applying the finite element method, the dependencies of the electrophysical and thermal properties on temperature, as well as the nonlinear magnetic properties (main magnetization curves) of ferromagnetic materials. Mathematical modelling of the distribution of coupled fields should be started in a two-dimensional formulation (a much more complicated three-dimensional formulation and the corresponding software can be used later to refine the results).Индукционные плиты представляют собой относительно новый класс современной электробытовой техники – кухонные электрические плиты, которые разогревают металлическую посуду вихревыми токами, создаваемыми электромагнитным полем частотой 20-100 кГц. Представляет значительный интерес исследование мультифизических (электромагнитных, тепловых и механических) процессов, протекающих в индукционных плитах в процессе их эксплуатации, а также разработка методики расчета и проектирования их конструктивных элементов. Полученные результаты должны быть рассчитаны на использование в практике конструирования бытовых индукционных плит, а также в учебном процессе для подготовки специалистов по соответствующей учебной программе. Количество опубликованных работ, посвященных компьютерному моделированию процессов в индукционных кухонных плитах, на много порядков меньше, чем количество публикаций по вопросам хорошо развитого численного анализа мультифизических явлений в промышленных индукционных нагревателях. В статье приведен обзор и анализ публикаций, главным образом опубликованных в зарубежных изданиях, посвященных мультифизическому компьютерному моделированию электромагнитных и тепловых процессов и явлений в индукционных кухонных плитах и нагреваемой посуде. Предложены направления дальнейших исследований: целесообразно учесть при применении метода конечных элементов зависимости электрофизических и теплофизических свойств от температуры, а также нелинейные магнитные свойства (основные кривые намагниченности) ферромагнитных материалов. Математическое моделирование распределения связанных полей целесообразно начать в двумерной постановке (значительно более сложная трехмерная постановка и соответствующее программное обеспечение могут быть использованы позднее для уточнения полученных результатов).Індукційні плити являють собою відносно новий клас сучасної електропобутової техніки – кухонні електричні плити, які розігрівають металевий посуд вихровими струмами, які створюються електромагнітним полем частотою 20-100 кГц. Представляє значний інтерес дослідження мультифізичних (електромагнітних, теплових і механічних) процесів, що протікають в індукційних плитах в процесі їх експлуатації, а також розробка методики розрахунку і проектування їх конструктивних елементів. Отримані результати мають бути розраховані на використання в практиці конструювання побутових індукційних плит, а також у навчальному процесі для підготовки фахівців за відповідною навчальною програмою. Кількість опублікованих робіт, присвячених комп’ютерному моделюванню процесів в індукційних кухонних плитах, на багато порядків менше, ніж кількість публікацій з питань добре розвинутого чисельного аналізу мультифізичних явищ у промислових індукційних нагрівачах. У статті наведено огляд і аналіз публікацій, головним чином опублікованих у закордонних виданнях, присвячених мультифізичному комп’ютерному моделюванню електромагнітних і теплових процесів і явищ в індукційних кухонних плитах і посуді, що нагрівається. Запропоновані напрямки подальших досліджень: доцільно врахувати при застосуванні метода скінчених елементів залежності електрофізичних та теплофізичних властивостей матеріалів від температури, а також нелінійні магнітні властивості (основні криві намагніченості) феромагнітних матеріалів. Математичне моделювання розподілу зв’язаних полів доцільно розпочати у двовимірній постановці (значно більш складна тривимірна постановка та відповідне програмне забезпечення можуть бути використані пізніше для уточнення отриманих результатів)

Next-generation sequencing reveals substantial genetic contribution to dementia with Lewy bodies

Dementia with Lewy bodies (DLB) is the second most common neurodegenerative dementia after Alzheimer's disease. Although an increasing number of genetic factors have been connected to this debilitating condition, the proportion of cases that can be attributed to distinct genetic defects is unknown. To provide a comprehensive analysis of the frequency and spectrum of pathogenic missense mutations and coding risk variants in nine genes previously implicated in DLB, we performed exome sequencing in 111 pathologically confirmed DLB patients. All patients were Caucasian individuals from North America. Allele frequencies of identified missense mutations were compared to 222 control exomes. Remarkably, ~ 25% of cases were found to carry a pathogenic mutation or risk variant in APP, GBA or PSEN1, highlighting that genetic defects play a central role in the pathogenesis of this common neurodegenerative disorder. In total, 13% of our cohort carried a pathogenic mutation in GBA, 10% of cases carried a risk variant or mutation in PSEN1, and 2% were found to carry an APP mutation. The APOE ε4 risk allele was significantly overrepresented in DLB patients (p-value < 0.001). Our results conclusively show that mutations in GBA, PSEN1, and APP are common in DLB and consideration should be given to offer genetic testing to patients diagnosed with Lewy body dementia

Clinical Conditions “Suggestive of Progressive Supranuclear Palsy”—Diagnostic Performance

Background: The Movement Disorder Society diagnostic criteria for progressive supranuclear palsy introduced the diagnostic certainty level “suggestive of progressive supranuclear palsy” for clinical conditions with subtle signs, suggestive of the disease. This category aims at the early identification of patients, in whom the diagnosis may be confirmed as the disease evolves. Objective: To assess the diagnostic performance of the defined clinical conditions suggestive of progressive supranuclear palsy in an autopsy-confirmed cohort. Methods: Diagnostic performance of the criteria was analyzed based on retrospective clinical data of 204 autopsy-confirmed patients with progressive supranuclear palsy and 216 patients with other neurological diseases. Results: The conditions suggestive of progressive supranuclear palsy strongly increased the sensitivity compared to the National Institute of Neurological Disorders and Stroke and Society for Progressive Supranuclear Palsy criteria. Within the first year after symptom onset, 40% of patients with definite progressive supranuclear palsy fulfilled criteria for suggestive of progressive supranuclear palsy. Two-thirds of patients suggestive of progressive supranuclear palsy evolved into probable progressive supranuclear palsy after an average of 3.6 years. Application of the criteria for suggestive of progressive supranuclear palsy reduced the average time to diagnosis from 3.8 to 2.2 years. Conclusions: Clinical conditions suggestive of progressive supranuclear palsy allow earlier identification of patients likely to evolve into clinically possible or probable progressive supranuclear and to have underlying progressive supranuclear palsy pathology. Further work needs to establish the specificity and positive predictive value of this category in real-life clinical settings, and to develop specific biomarkers that enhance their diagnostic accuracy in early disease stages

MAPT p.V363I mutation: A rare cause of corticobasal degeneration

Objective: Patients with corticobasal syndrome (CBS) present with heterogeneous clinical features, including asymmetric parkinsonism, dyspraxia, aphasia, and cognitive impairment; to better understand the genetic etiology of this rare disease, we undertook a genetic analysis of microtubule-associated protein tau (MAPT). Methods: We performed a genetic evaluation of MAPT mutations in 826 neurologically healthy controls and 173 cases with CBS using the Illumina NeuroChip genotyping array. Results: We identified 2 patients with CBS heterozygous for a rare mutation in MAPT (p.V363I) that is located in the highly conserved microtubule-binding domain. One patient was pathologically confirmed and demonstrated extensive 4-repeat-tau-positive thread pathology, achromatic neurons, and astrocytic plaques consistent with corticobasal degeneration (CBD). Conclusions: We report 2 CBS cases carrying the rare p.V363I MAPT mutation, one of which was pathologically confirmed as CBD. Our findings support the notion that this rare coding change is pathogenic

Uncovering spatiotemporal patterns of atrophy in progressive supranuclear palsy using unsupervised machine learning

Data availability: Source data are not publicly available but non-commercial academic researcher requests may be made to the chief investigators of the seven source studies, subject to data access agreements and conditions that preserve participant anonymity. The underlying SuStaIn model code is publicly available at https://github.com/ucl-pond/pySuStaIn.68 .Supplementary data: available online at: https://academic.oup.com/braincomms/article/5/2/fcad048/7067775#398676040 .Copyright © The Author(s) 2023. To better understand the pathological and phenotypic heterogeneity of progressive supranuclear palsy and the links between the two, we applied a novel unsupervised machine learning algorithm (Subtype and Stage Inference) to the largest MRI data set to date of people with clinically diagnosed progressive supranuclear palsy (including progressive supranuclear palsy–Richardson and variant progressive supranuclear palsy syndromes). Our cohort is comprised of 426 progressive supranuclear palsy cases, of which 367 had at least one follow-up scan, and 290 controls. Of the progressive supranuclear palsy cases, 357 were clinically diagnosed with progressive supranuclear palsy–Richardson, 52 with a progressive supranuclear palsy–cortical variant (progressive supranuclear palsy–frontal, progressive supranuclear palsy–speech/language, or progressive supranuclear palsy–corticobasal), and 17 with a progressive supranuclear palsy–subcortical variant (progressive supranuclear palsy–parkinsonism or progressive supranuclear palsy–progressive gait freezing). Subtype and Stage Inference was applied to volumetric MRI features extracted from baseline structural (T1-weighted) MRI scans and then used to subtype and stage follow-up scans. The subtypes and stages at follow-up were used to validate the longitudinal consistency of subtype and stage assignments. We further compared the clinical phenotypes of each subtype to gain insight into the relationship between progressive supranuclear palsy pathology, atrophy patterns, and clinical presentation. The data supported two subtypes, each with a distinct progression of atrophy: a ‘subcortical’ subtype, in which early atrophy was most prominent in the brainstem, ventral diencephalon, superior cerebellar peduncles, and the dentate nucleus, and a ‘cortical’ subtype, in which there was early atrophy in the frontal lobes and the insula alongside brainstem atrophy. There was a strong association between clinical diagnosis and the Subtype and Stage Inference subtype with 82% of progressive supranuclear palsy–subcortical cases and 81% of progressive supranuclear palsy–Richardson cases assigned to the subcortical subtype and 82% of progressive supranuclear palsy–cortical cases assigned to the cortical subtype. The increasing stage was associated with worsening clinical scores, whilst the ‘subcortical’ subtype was associated with worse clinical severity scores compared to the ‘cortical subtype’ (progressive supranuclear palsy rating scale and Unified Parkinson’s Disease Rating Scale). Validation experiments showed that subtype assignment was longitudinally stable (95% of scans were assigned to the same subtype at follow-up) and individual staging was longitudinally consistent with 90% remaining at the same stage or progressing to a later stage at follow-up. In summary, we applied Subtype and Stage Inference to structural MRI data and empirically identified two distinct subtypes of spatiotemporal atrophy in progressive supranuclear palsy. These image-based subtypes were differentially enriched for progressive supranuclear palsy clinical syndromes and showed different clinical characteristics. Being able to accurately subtype and stage progressive supranuclear palsy patients at baseline has important implications for screening patients on entry to clinical trials, as well as tracking disease progression.W.J.S. is supported by a Wellcome Trust Clinical PhD fellowship (220582/Z/20/Z). C.S. is supported by the UK Research and Innovation Medical Research Council (MR/S03546X/1). M.B. is supported by a fellowship award from the Alzheimer’s Society, UK (AS-JF-19a-004-517), and the UK Dementia Research Institute. D.M.C. is supported by the UK Dementia Research Institute, as well as Alzheimer’s Research UK (ARUK-PG2017-1946), and the University College London/University College London Hospitals, National Institute for Health and Care Research Biomedical Research Centre. H.H. is supported by the National Institutes of Health (R01AG038791, U19AG063911). A.L.Y. is supported by a Skills Development Fellowship from the Medical Research Council (MR/T027800/1). N.P.O. is a UK Research and Innovation Future Leaders Fellow (MR/S03546X/1). L.V.V. is supported by the National Institutes of Health (R01AG038791, K23AG073514) and the Alzheimer’s Association. D.C.A. is supported by the Engineering and Physical Sciences Research Council (EP/M020533/1), Medical Research Council (MR/T046422/1), and Wellcome Trust (UNS113739). J.B.R. is supported by the Wellcome Trust (220258), National Institute for Health and Care Research Cambridge Biomedical Research Centre (BRC-1215-20014), PSP Association, Evelyn Trust, and Medical Research Council (SUAG051 R101400). H.R.M. is supported by Parkinson’s UK, Cure Parkinson’s Trust, PSP Association, CBD Solutions, Drake Foundation, Medical Research Council, and the Michael J Fox Foundation. A.L.B. is supported by the National Institutes of Health (U19AG063911, R01AG038791, R01AG073482, and U24AG057437), the Rainwater Charitable Foundation, the Bluefield Project to Cure FTD, and the Alzheimer’s Association and the Association for Frontotemporal Degeneration. J.D.R. is supported by the Miriam Marks Brain Research UK Senior Fellowship and has received funding from a Medical Research Council Clinician Scientist Fellowship (MR/M008525/1) and the National Institute for Health and Care Research Rare Disease Translational Research Collaboration (BRC149/NS/MH). P.A.W. is supported by a Medical Research Council Skills Development Fellowship (MR/T027770/1). The Dementia Research Centre is supported by Alzheimer’s Research UK, Alzheimer’s Society, Brain Research UK, and The Wolfson Foundation. This work was supported by the National Institute for Health and Care Research University College London Hospitals Biomedical Research Centre, the Leonard Wolfson Experimental Neurology Centre (LWENC) Clinical Research Facility, and the UK Dementia Research Institute, which receives its funding from UK DRI Ltd., funded by the UK Medical Research Council, Alzheimer’s Society, and Alzheimer’s Research UK. The PROSPECT study is funded by the PSP Association and CBD Solutions. The 4-Repeat Tauopathy Neuroimaging Initiative (4RTNI) and FTLDNI are funded by the National Institutes of Health Grant (R01 AG038791) and through generous contributions from the Tau Research Consortium. Both are coordinated through the University of California, San Francisco, Memory and Aging Center. 4RTNI data are disseminated by the Laboratory for Neuro Imaging at the University of Southern California

Radiological biomarkers for diagnosis in PSP: Where are we and where do we need to be?

PSP is a pathologically defined neurodegenerative tauopathy with a variety of clinical presentations including typical Richardson's syndrome and other variant PSP syndromes. A large body of neuroimaging research has been conducted over the past two decades, with many studies proposing different structural MRI and molecular PET/SPECT biomarkers for PSP. These include measures of brainstem, cortical and striatal atrophy, diffusion weighted and diffusion tensor imaging abnormalities, [18F] fluorodeoxyglucose PET hypometabolism, reductions in striatal dopamine imaging and, most recently, PET imaging with ligands that bind to tau. Our aim was to critically evaluate the degree to which structural and molecular neuroimaging metrics fulfill criteria for diagnostic biomarkers of PSP. We queried the PubMed, Cochrane, Medline, and PSYCInfo databases for original research articles published in English over the past 20 years using postmortem diagnosis or the NINDS-SPSP criteria as the diagnostic standard from 1996 to 2016. We define a five-level theoretical construct for the utility of neuroimaging biomarkers in PSP, with level 1 representing group-level findings, level 2 representing biomarkers with demonstrable individual-level diagnostic utility, level 3 representing biomarkers for early disease, level 4 representing surrogate biomarkers of PSP pathology, and level 5 representing definitive PSP biomarkers of PSP pathology. We discuss the degree to which each of the currently available biomarkers fit into this theoretical construct, consider the role of biomarkers in the diagnosis of Richardson's syndrome, variant PSP syndromes and autopsy confirmed PSP, and emphasize current shortfalls in the field. © 2017 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society

Tremor in cervical dystonia

Background: Cervical dystonia (CD) is the most common form of focal dystonia encountered in the clinic. Approximately one-third of CD patients have co-existing tremor in the head and hands. Assessment of tremor as regular or irregular in context of its oscillation trajectory, frequency, and amplitude is a major clinical challenge and can confound the diagnosis of CD. The misdiagnosis may lead to therapeutic failures, poor quality of life, and poor utilization of medical and financial resources.Methods: We analyzed the largest cohort of CD patients (n = 3117) available to date, collected from 37 movement disorder centers in North America, Europe, and Asia. We used machine learning to determine what clinical features from clinician reports predicted the presence of tremor as well as its regular or irregular appearance.Results: Out of 3,117 CD patients, 1,367 had neck tremor. The neck tremor was interpreted as irregular in 1,022, regular in 345, and mixed (both irregular and regular) in 442. A feature importance analysis determined that greater severity of CD, longer disease duration, and older age, in descending order, predicted the presence of neck tremor. The probability of neck tremor was reduced if the dystonia affected other body parts in addition to the neck. We also found a significantly heightened risk for developing neck tremor in women. An additional feature importance analysis indicated that increased severity of dystonia affecting other body parts, severity of CD, and prolonged disease duration was associated with a lower likelihood of regular neck tremor while increased age predicted a higher likelihood.Conclusion: Machine learning recognized the most relevant clinical features that can predict concurrent neck tremor and its irregularity in a large multi-center dystonia cohort. These results may facilitate a more accurate description of neck tremor and improved care path in CD