Validating a new methodology for optical probe design and image registration in fNIRS studies

Functional near-infrared spectroscopy (fNIRS) is an imaging technique that relies on the principle of shining near-infrared light through tissue to detect changes in hemodynamic activation. An important methodological issue encountered is the creation of optimized probe geometry for fNIRS recordings. Here, across three experiments, we describe and validate a processing pipeline designed to create an optimized, yet scalable probe geometry based on selected regions of interest (ROIs) from the functional magnetic resonance imaging (fMRI) literature. In experiment 1, we created a probe geometry optimized to record changes in activation from target ROIs important for visual working memory. Positions of the sources and detectors of the probe geometry on an adult head were digitized using a motion sensor and projected onto a generic adult atlas and a segmented head obtained from the subject's MRI scan. In experiment 2, the same probe geometry was scaled down to fit a child's head and later digitized and projected onto the generic adult atlas and a segmented volume obtained from the child's MRI scan. Using visualization tools and by quantifying the amount of intersection between target ROIs and channels, we show that out of 21 ROIs, 17 and 19 ROIs intersected with fNIRS channels from the adult and child probe geometries, respectively. Further, both the adult atlas and adult subject-specific MRI approaches yielded similar results and can be used interchangeably. However, results suggest that segmented heads obtained from MRI scans be used for registering children's data. Finally, in experiment 3, we further validated our processing pipeline by creating a different probe geometry designed to record from target ROIs involved in language and motor processing

Выделение некоторых органохлорсиланов методом препаративной газовой хроматографии

The preparative gas chromatography method has been used for isolation and analysis of the organochlorsilanes isomers. The reaction of the organochlorsilanes with vapour of the water in the air has been studied. The method for isolation of the organochlorsilanes is proposed. It is based on using chromatographic column with efficiency up to 10000 theoretical plates. A high degree of purity (up to 99%) of the isolated compounds is achieved by an increase of separation selectivity, which is turned results from a temperature decrease. The effect of the parameters of chromatographic experiment (the column length, impregnation degree, the rate of gas-carrier) on the isolation of the compounds boiling up to 400o C was investigated.Метод газовой хроматографии, основанный на использовании хроматографических колонок с эффективностью до 10000 теоретических тарелок, предложен для выделения и анализа некоторых изомеров органохлорсиланов, которые активно реагируют с влагой воздуха. Высокая чистота (до 99%) выделенных соединений достигается за счет увеличения селективности путем понижения температуры. Исследованы условия выделения некоторых изомеров органо- хлорсиланов c температурами кипения до 400о С методом препаративной газовой хроматографии. Показаны пути преодоления методических трудностей, возникающих при выделении высококипящих изомеров. Приведены данные по выделению изомеров хлорсиланов, содержащих различные радикалы (метил-, винил-, фенил-, адамантил-

Использование отечественных кремнийорганических жидкостей в качестве неподвижных фаз в газожидкостной хроматографии

The thermal stability of organosilicon stationary phases for gas-liquid chromatography has been tested under conditions approximating the real operation of chromatographic column.Проведены испытания термостойкости отечественных кремнийорганических неподвижных фаз в условиях, приближенных к обычным условиям работы хроматографических колонн. Показано, что значения верхнего температурного предела большинства кремнийорганических неподвижных фаз были завышены. Определены значения верхнего температурного предела этих неподвижных фаз, соответствующие современным требования

Выделение некоторых высококипящих элементоорганических соединений методом препаративной газовой хроматографии

Preparative gas chromatography is proposed to isolate some high-boiling organometallic compounds. Isolation of high-boiling substances should be conducted at a column temperature significantly below the boiling point, because most isolated compounds are thermally unstable at such temperatures. Stationary phases for preparative gas chromatography have a temperature limit of 350°C. The reduction of the column temperature is based on simultaneous changing the parameters of the chromatographic experiment (column length, impregnation degree, flow rate of the carrier gas). The influence of reducing the column temperature on the shape of the chromatographic peak is shown. The peak has an asymmetric shape, and its width increases. Therefore, the possibility of high-boiling substances preparative isolation depends on temperature decrease as the column separation efficiency is maintained.Метод препаративной газовой хроматографии предложен для выделения некоторых высококипящих элементоорганических соединений. Выделение высококипящих веществ необходимо проводить при температуре, значительно ниже температуры кипения, так как большинство выделяемых соединений термически неустойчивы при таких температурах. Неподвижные фазы для препаративной газовой хроматографии имеют температурный предел 350ºС. Рассмотрены особенности выделения высококипящих веществ при снижении температуры колонки относительно температуры кипения вещества. Понижение температуры колонки достигнуто путем одновременного изменения параметров хроматографического опыта (длины колонки, степени пропитки, скорости газа-носителя). Однако при увеличении отношения температуры кипения к температуре колонки наблюдается изменение формы пика, возрастание его ширины. Поэтому возможность препаративного выделения высококипящих веществ зависит от снижения температуры колонки при сохранении эффективности разделения

Анализ полиметилфенилсилоксановой жидкости ПФМС-5 методом ВЭЖХ

Polymethylphenylsiloxane liquid PFMS-5 is used as a high temperature heat transfer fluid and a working fluid in the high-vacuum pumps. It is one of the most high-temperature stationary phases in gas chromatography. However, some samples have an upper temperature limit of 280 to 350°С. The composition of this fluid was studied by HPLC. For identification a set of compounds isolated by preparative gas chromatography was obtained. A previously synthesized product consisting of linear polymethylphenylsiloxanes with the number of silicon atoms from 3 to 120 was used. By using a diode array detector the UV-spectra of all the components in the obtained chromatogram were recorded. On the basis of these data it can be concluded that the liquid PFMS-5 consists of polymer homologues with the number of silicon atoms from 3 to 13. In addition to linear methylphenyloligosiloxanes methylphenylsiloxanes of other structure are present in the liquid. Linear methylphenyloligosiloxanes were identifiedПолиметилфенилсилоксановая жидкость ПФМС-5 применяется как высокотемпературный теплоноситель, рабочая жидкость в высоковакуумных насосах и является одной из самых высокотемпературных стационарных фаз в газовой хроматографии. Однако некоторые образцы имеют верхний температурный предел от 280 до 350°С. Состав этой жидкости был изучен методом ВЭЖХ. Для идентификации был получен набор веществ, выделенных препаративной газовой хроматографией. Был использован ранее синтезированный продукт, состоящий из линейных полиметилфенилсилоксанов с числом атомов кремния от 3 до 120. С помощью детектора с диодной матрицей были получены Уф-спектры всех компонентов, представленных на хроматограмме. На основании полученных данных можно заключить, что жидкость состоит из полимергомологов с числом атомов кремния от 3 до 13. Помимо линейных олигосилоксанов в жидкости присутствуют метилфенилсилоксаны другого строения. Линейные метилфенилолигосилоксаны были идентифицированы

Выделение некоторых кремнийорганических гетероциклических соединений методом препаративной газовой хроматографии

The preparative gas chromatography method has been used for isolation of heterocyclic organosilicon compounds boiling up to 400o C. The ways are shown for solution of problems which arise in the course of isolation of such high boiling substances.Проведено выделение ряда кремнийорганических гетероциклических соединений c температурами кипения до 400 о С методом препаративной газовой хроматографии. Показаны пути преодоления методических трудностей, возникающих при выделении подобных веществ

Subliminal versus supraliminal stimuli activate neural responses in anterior cingulate cortex, fusiform gyrus and insula:a meta-analysis of fMRI studies

Background: Non-conscious neural activation may underlie various psychological functions in health and disorder. However, the neural substrates of non-conscious processing have not been entirely elucidated. Examining the differential effects of arousing stimuli that are consciously, versus unconsciously perceived will improve our knowledge of neural circuitry involved in non-conscious perception. Here we conduct preliminary analyses of neural activation in studies that have used both subliminal and supraliminal presentation of the same stimulus. Methods: We use Activation Likelihood Estimation (ALE) to examine functional Magnetic Resonance Imaging (fMRI) studies that uniquely present the same stimuli subliminally and supraliminally to healthy participants during functional magnetic resonance imaging (fMRI). We included a total of 193 foci from 9 studies representing subliminal stimulation and 315 foci from 10 studies representing supraliminal stimulation. Results: The anterior cingulate cortex is significantly activated during both subliminal and supraliminal stimulus presentation. Subliminal stimuli are linked to significantly increased activation in the right fusiform gyrus and right insula. Supraliminal stimuli show significantly increased activation in the left rostral anterior cingulate. Conclusions: Non-conscious processing of arousing stimuli may involve primary visual areas and may also recruit the insula, a brain area involved in eventual interoceptive awareness. The anterior cingulate is perhaps a key brain region for the integration of conscious and non-conscious processing. These preliminary data provide candidate brain regions for further study in to the neural correlates of conscious experience

Bringing ancient loess critical zones into a new era of sustainable development goals

Critical Zone Observatories (CZOs) have been established initially in natural environments to monitor CZ processes. A new generation of CZOs has been extended to human-modified landscapes to address the impacts of climate change and human-caused actions such as erosion, droughts, floods, and water resource pollution. This review focuses on numerous plot, field, and regional scale studies conducted in the CZO facilities distributed across the China Loess Plateau (CLP). The CLP CZO features the world's largest and deepest loess deposits, highly disturbed by human activities, and consists of a longitudinal series of monitoring sites. This observation system consists of plot, slope, watershed, and regional observatories and is promoted by large-scale comprehensive experiments to achieve multiscale observations. Deep soil boreholes, hydro-geophysical tools, multiple tracers-based techniques, proximal and remote sensing techniques, and automatic monitoring equipment are implemented to monitor CZ processes. Observation and modeling of critical hydrological and biogeochemical processes (e.g., water, nutrients, carbon, and microbial activities) in land surface and deep loess deposits across CLP CZOs have unveiled crucial insights into human-environment interactions and sustainability challenges. Large-scale ecological efforts such as revegetation and engineering such as check dam construction have effectively mitigated flood and soil erosion while enhancing deep soil carbon sequestration. However, these interventions can yield both benefits and drawbacks, impacting deep soil water, groundwater recharge, and agricultural production. Converting arable cropland to orchards for increased income has raised nitrate accumulation in the deep vadose zone, posing a risk of groundwater pollution. These findings, combined with the CZ data, have identified knowledge exchange opportunities to unravel diverse factors within the relations of agriculture, ecosystem, and environment. These could directly improve local livelihoods and eco-environmental conditions by optimizing land use and management practices, increasing water use efficiency, and reducing fertilizer application. These efforts contribute towards Sustainable Development Goals (SDGs) and environmental policies. Overall, studies within the CLP have provided significant scientific advancements and guidance on managing CZ processes and services with regional SDGs, that may be transferable to other highly disturbed regions of the world

Treatment of developmental dyslexia: A review

Remarkably few research articles on the treatment of developmental dyslexia were published during the last 25 years. Some treatment research arose from the temporal processing theory, some from the phonological deficit hypothesis and some more from the balance model of learning to read and dyslexia. Within the framework of that model, this article reviews the aetiology of dyslexia sub-types, the neuropsychological rationale for treatment, the treatment techniques and the outcomes of treatment research. The possible mechanisms underlying the effects of treatment are discussed. © 2005 Informa UK Ltd All rights reserved

The BrainMap strategy for standardization, sharing, and meta-analysis of neuroimaging data

<p>Abstract</p> <p>Background</p> <p>Neuroimaging researchers have developed rigorous community data and metadata standards that encourage meta-analysis as a method for establishing robust and meaningful convergence of knowledge of human brain structure and function. Capitalizing on these standards, the BrainMap project offers databases, software applications, and other associated tools for supporting and promoting quantitative coordinate-based meta-analysis of the structural and functional neuroimaging literature.</p> <p>Findings</p> <p>In this report, we describe recent technical updates to the project and provide an educational description for performing meta-analyses in the BrainMap environment.</p> <p>Conclusions</p> <p>The BrainMap project will continue to evolve in response to the meta-analytic needs of biomedical researchers in the structural and functional neuroimaging communities. Future work on the BrainMap project regarding software and hardware advances are also discussed.</p