Instrumental Transfer Research Articles

Effects of digital fringe projection operational parameters on detecting powder bed defects in additive manufacturing

Additive manufacturing is a technology transforming traditional production timelines. Specifically, metal additive manufacturing (MAM) has been increasingly adopted by a variety of industries, not only to prototype, but also to fulfill full production scale applications with much lower lead times. Like any maturing manufacturing technology, developments in verifying and validating processes are necessary to support continuous growth. Due to the complex nature of MAM, part quality and repeatability remain integral challenges that inhibit further adoption of MAM for critical component production. In this study, we present data taken from a developing in-process monitoring system designed to measure and detect powder bed defects (PBDs) in powder bed fusion MAM systems using surface height maps created with structured light illumination. We showcase the feasibility of the monitoring technique for in-process implementation by detecting streak PBDs with varying severities (height, width) created in a lab environment. We present results of powder bed measurements for varying experimental parameters of the structured light system such as illumination angle, illumination pattern, and number of illuminations. We also present an expression used to determine experimental height noise based on input parameters for PBD detection based on the instrument transfer function of the structured light monitoring system for arbitrary pixel intensity noise contributions. With the results of PBD detection across across multiple experimental measurement parameters, we provide a best practices approach to in-process implementation of the monitoring system in powder bed fusion manufacturing.

INSTANCE – the Italian seismic dataset for machine learning

Abstract. The Italian earthquake waveform data are collected here in a dataset suited for machine learning analysis (ML) applications. The dataset consists of nearly 1.2 million three-component (3C) waveform traces from about 50 000 earthquakes and more than 130 000 noise 3C waveform traces, for a total of about 43 000 h of data and an average of 21 3C traces provided per event. The earthquake list is based on the Italian Seismic Bulletin (http://terremoti.ingv.it/bsi, last access: 15 February 2020​​​​​​​) of the Istituto Nazionale di Geofisica e Vulcanologia between January 2005 and January 2020, and it includes events in the magnitude range between 0.0 and 6.5. The waveform data have been recorded primarily by the Italian National Seismic Network (network code IV) and include both weak- (HH, EH channels) and strong-motion (HN channels) recordings. All the waveform traces have a length of 120 s, are sampled at 100 Hz, and are provided both in counts and ground motion physical units after deconvolution of the instrument transfer functions. The waveform dataset is accompanied by metadata consisting of more than 100 parameters providing comprehensive information on the earthquake source, the recording stations, the trace features, and other derived quantities. This rich set of metadata allows the users to target the data selection for their own purposes. Much of these metadata can be used as labels in ML analysis or for other studies. The dataset, assembled in HDF5 format, is available at http://doi.org/10.13127/instance (Michelini et al., 2021).

Guaranteeing positive destinations for youth in a Danish municipality: the transfer, translation, and transformation of a policy instrument

In 2019, Hjørring Municipality launched a comprehensive Youth Guarantee programme to ensure ‘positive destinations’ for the municipality’s youth. The strategy was explicitly inspired by Edinburgh’s interpretation of the Scottish Youth Guarantee. In this article, we conceptualize the Youth Guarantee as a policy instrument and unpack the transfer, translation, and transformation from the initial coincidental inspiration to the policy instrument developing a ‘life of its own’. The instrument serves as a vehicle for creating a constituency centred on a value-based governing paradigm, alliances, and the enthusiastic spread of the Youth Guarantee spirit. The case serves as an example of how the transfer, translation, and transformation processes of a policy instrument into a foreign legal context can play out, as well as how dominating forms of governance centred on values, alliances, and common enthusiasm in the constituency – and even the contours of a governance paradigm – can be teased out through such an endeavour.

Δ 9-Tetrahydrocannabinol During Adolescence Reprograms the Nucleus Accumbens Transcriptome, Affecting Reward Processing, Impulsivity, and Specific Aspects of Cocaine Addiction-Like Behavior in a Sex-Dependent Manner.

BackgroundCannabis exposure during adolescence is associated with emotional and motivational alterations that may entail an enhanced risk of developing psychiatric disorders. In rodent models, exposure to cannabinoids during adolescence leads to increased self-administration of opiates and cocaine, however, the psychological and neural mechanisms and the sex-specificity of this phenomenon are largely unknown.MethodsWe exposed male and female adolescent rats to Δ9-tetrahydrocannabinol (THC) and studied at adulthood the effects of such treatment on psychological processes related to reward, such as Pavlovian conditioned approach, Pavlovian to instrumental transfer, habit formation and waiting impulsivity. In the light of these data and given the involvement of the nucleus accumbens in the processes examined, we performed an RNASeq transcriptomic study and assessed cocaine addiction-like behavior.ResultsTHC exposure increased goal-tracking (in males and females) and enhanced Pavlovian to instrumental transfer (especially in males) but did not affect habit formation. THC-exposed rats exhibited subtle, state-dependent changes in premature responding in the 2-CSRTT task. RNASeq data showed gene expression alterations in a marked sex-specific manner. While no effects were found on the acquisition of cocaine self-administration or punished drug-seeking, rats exposed to THC self-administered more cocaine under a progressive ratio schedule (males), had a higher rebound upon returning to continuous access to the drug (females) and showed reduced drug-seeking after 30 days of withdrawal (females).ConclusionsAdolescent THC affects specific aspects of reward- (and cocaine-) guided behavior and the function of a key brain region mediating these effects, in a remarkable sex-specific manner.

Research frontiers of chemical detection and measurements

Abstract Over the past decade, the global research agenda focused on finding paths to the future development of chemistry. Chemical detection and measurement is an important and fundamental discipline of chemistry and it keeps playing a significant role in chemical research in the next 10–15 years. The goal of chemical detection is to overcome the state-of-art temporospatial resolution limit. Meanwhile, the application of modern chemical technology to serve human health is also highly concerned. We have summarized 10 aspects related to the field, including complex samples analysis, biomacromolecule structure and function, single-entity analysis, large-scale scientific instrument, rapid chemical and electron transfer processes, big data and artificial intelligence, bioimaging, in vivo real-time detection, biomolecule recognition and disease therapy, and public health screening. In this review, we outlined the history and the frontiers of chemical detection and measurements in enhancing the development of chemical sciences. Moreover, we also focused on the major challenges that should be solved in the future in which researchers should develop new techniques and analytical methods to drastically accelerate chemical sciences.

Ergonomic Consideration of Sight Shifts between the Microscopic and Macroscopic Environments in Microscopic Dentistry for Inexperienced Operators.

Due to the rising popularity of Dental Operating Microscopes, the issue of their ergonomic use has become an important topic. To verify its impact on dental teams’ ergonomics, the aspect of working in two distinct environments was examined. The research was performed on a group of 82 dentists regarding the number and character of shifts from the microscopic environment to the macroscopic one. The results revealed the shifts constitute a significant part of an inexperienced DOM operator’s work. Because such shifts, when performed repeatedly and in short succession, may influence the operator’s vision and comfort, they should be considered ergonomically detrimental. Having indicated the problem, the article puts forth a solution in the form of an instrument transfer methodology. The proposed adjustment has the potential of improving the quality of work for DOM operators quickly and efficiently by significantly reducing the number of shifts between the environments.

General Pavlovian-instrumental transfer tests reveal selective inhibition of the response type – whether Pavlovian or instrumental – performed during extinction

The present experiments examined whether extinction of a stimulus predicting food affects the ability of that stimulus to energize instrumental performance to obtain food. We first used a general Pavlovian instrumental transfer (PIT) paradigm in which rats were first given Pavlovian conditioning with a stimulus predicting one type of food outcome and were then trained to lever press for a different food outcome. We found that the Pavlovian stimulus enhanced performance of the lever press response and that this enhancement was preserved after extinction of that stimulus (Experiment 1) even when the context was manipulated to favor the expression of extinction (Experiment 2). Next, we assessed whether extinction influenced the excitatory effect of a stimulus when it was trained as a discriminative stimulus. Extinction of this stimulus alone had no effect on its ability to control instrumental performance; however, when extinguished with its associated lever press response, discriminative control was lost (Experiments 3 and 4). Finally, after instrumental and Pavlovian training, we extinguished a Pavlovian stimulus predicting one food outcome with a lever press response that delivered a different outcome. In a general PIT test, we found this extinction abolished the ability of the Pavlovian stimulus to elevate responding on a lever trained with a different outcome, revealing for the first time that extinction can abolish the general PIT effect. We conclude that extinction can produce an inhibitory association between the stimulus and the general response type, whether Pavlovian or instrumental, performed during the extinction training.

Elmelegy’s modified technique for durable forehead rejuvenation using a novel instrument and fat transfer

Elmelegy’s modified technique for durable forehead rejuvenation using a novel instrument and fat transfer

Define and measure the dimensional accuracy of two-photon laser lithography based on its instrument transfer function

Two-photon polymerization (TPP) is a powerful technique for direct three-dimensional (3D) micro- and nanomanufacturing owing to its unique ability of writing almost arbitrary structures of various materials. In this paper, a novel method is proposed to quantitatively define and measure the dimensional accuracy of TPP tools based on the concept of instrument transfer function (ITF). A circular linear-chirp pattern is designed for characterizing the ITF. Such a pattern is arranged in a linear chirp function with respect to its radial distance from the pattern centre, thus, well representing a signal with a quasi-flat amplitude over a given spectral bandwidth. In addition, the pattern is rotational symmetric, therefore, it is well suited for characterizing the ITF in different angular directions to detect angular-dependent asymmetries. The feasibility of the proposed method is demonstrated on a commercial TPP tool. The manufactured pattern is calibrated by a metrological large range atomic force microscope (AFM) using a super sharp AFM tip, thus the dimensional accuracy and angular-dependent anisotropy of the TPP tool have been well characterized quantitatively. The proposed method is easy to use and reveals the dimensional accuracy of TPP tools under real manufacturing conditions, which concerns not only the optical focus spot size of the exposing laser but also influencing factors such as material shrinkage, light–matter interaction and process parameters.

The instrument transfer function for optical measurements of surface topography

For optical measurements of areal surface topography, the instrument transfer function (ITF) quantifies height response as a function of the lateral spatial frequency content of the surface. The ITF is used widely for optical full-field instruments such as Fizeau interferometers, confocal microscopes, interference microscopes, and fringe projection systems as a more complete way to characterize lateral resolving power than a single number such as the Abbe limit. This paper is a comprehensive review of the ITF, including standardized definitions, ITF prediction using theoretical simulations, common uses, limitations, and evaluation techniques using material measures.

Associative processes in addiction relapse models: A review of their Pavlovian and instrumental mechanisms, history, and terminology

Animal models of relapse to drug-seeking have borrowed heavily from associative learning approaches. In studies of relapse-like behaviour, animals learn to self-administer drugs then receive a period of extinction during which they learn to inhibit the operant response. Several triggers can produce a recovery of responding which form the basis of a variety of models. These include the passage of time (spontaneous recovery), drug availability (rapid reacquisition), extinction of an alternative response (resurgence), context change (renewal), drug priming, stress, and cues (reinstatement). In most cases, the behavioural processes driving extinction and recovery in operant drug self-administration studies are similar to those in the Pavlovian and behavioural literature, such as context effects. However, reinstatement in addiction studies have several differences with Pavlovian reinstatement, which have emerged over several decades, in experimental procedures, associative mechanisms, and terminology. Interestingly, in cue-induced reinstatement, drug-paired cues that are present during acquisition are omitted during lever extinction. The unextinguished drug-paired cue may limit the model’s translational relevance to cue exposure therapy and renders its underlying associative mechanisms ambiguous. We review major behavioural theories that explain recovery phenomena, with a particular focus on cue-induced reinstatement because it is a widely used model in addiction. We argue that cue-induced reinstatement may be explained by a combination of behavioural processes, including reacquisition of conditioned reinforcement and Pavlovian to Instrumental Transfer. While there are important differences between addiction studies and the behavioural literature in terminology and procedures, it is clear that understanding associative learning processes is essential for studying relapse.

Detection of Meniscal Tear Effects on Tibial Vibration Using Passive Knee Sound Measurements.

To evaluate whether non-invasive knee sound measurements can provide information related to the underlying structural changes in the knee following meniscal tear. These changes are explained using an equivalent vibrational model of the knee-tibia structure. First, we formed an analytical model by modeling the tibia as a cantilever beam with the fixed end being the knee. The knee end was supported by three lumped components with features corresponding with tibial stiffnesses, and meniscal damping effect. Second, we recorded knee sounds from 46 healthy legs and 9 legs with acute meniscal tears (n = 34 subjects). We developed an acoustic event ("click") detection algorithm to find patterns in the recordings, and used the instrumental variable continuous-time transfer function estimation algorithm to model them. The knee sound measurements yielded consistently lower fundamental mode decay rate in legs with meniscal tears ( 16 ±13 s - 1) compared to healthy legs ( 182 ±128 s - 1), p < 0.05. When we performed an intra-subject analysis of the injured versus contralateral legs for the 9 subjects with meniscus tears, we observed significantly lower natural frequency and damping ratio (first mode results for healthy: [Formula: see text]injured: [Formula: see text]) for the first three vibration modes (p < 0.05). These results agreed with the theoretical expectations gleaned from the vibrational model. This combined analytical and experimental method improves our understanding of how vibrations can describe the underlying structural changes in the knee following meniscal tear, and supports their use as a tool for future efforts in non-invasively diagnosing meniscal tear injuries.

The instrument transfer method in four handed dentistry in dental operating microscope as a module of a training program in the aspect of reduction of the dynamic load of the visual system of the operator

Resume. Introduction of a Dental Operating Microscope (DOM) in the clinical work can make some difficulties in operator’s work.In particular, to ensure the safety of the operator’s visual system and ergonomics of the work, the operator’s gaze should be continuously directed to the operating field. The instruments should be moved over the operating field by the assisting personnel, whose participation in the transfer is not complete until the evening nstrument is visible through the microscope and the operator is fully capable of controlling its movement. Instrument transfer method in DOM includes 3 steps: modified direct placement, predelivery, delivery and exchange of instruments. In the presented method the most important elements are the properly oriented end of the instrument by dental assistant and mutual grasp of instrument. The method allows to reduce the load on the operator’s visual system and to make four-handed work ergonomic. Key words: dental operating microscope (DOM), four-handed dentistry in DOM, instrument transfer in DOM, mutual grasp, visual system overload of dental operator.

Bias-free model fitting of correlated data in interferometry

Abstract In optical and infrared long-baseline interferometry, data often display significant correlated errors because of uncertain multiplicative factors such as the instrumental transfer function or the pixel-to-visibility matrix. In the context of model fitting, this situation often leads to a significant bias in the model parameters. In the most severe cases, this can can result in a fit lying outside of the range of measurement values. This is known in nuclear physics as Peelle’s Pertinent Puzzle. I show how this arises in the context of interferometry and determine that the relative bias is of the order of the square root of the correlated component of the relative uncertainty times the number of measurements. It impacts preferentially large datasets, such as those obtained in medium to high spectral resolution. I then give a conceptually simple and computationally cheap way to avoid the issue: model the data without covariances, estimate the covariance matrix by error propagation using the modelled data instead of the actual data, and perform the model fitting using the covariance matrix. I also show that a more imprecise but also unbiased result can be obtained from ignoring correlations in the model fitting.

A rapid response vaccine development strategy for newcastle disease in poultry

Poultry is a major source of protein in sub-Saharan Africa and many other lower-income regions. Newcastle disease virus (NCDV) comprises a significant threat toward poultry production. While NCDV vaccines are routinely used in developed countries, those used in sub-Saharan Africa are mostly imported and are not specific to locally circulating strains. Indeed, the lack of rapid, field-based NCDV detection and the absence of cost-effective production methods for pure, strain-specific vaccines hampers efficient poultry production throughout these regions. This remains a major problem for both subsistence and commercial farming.The aim for this study was firstly, to develop a field-based isothermal PCR assay for NCDV detection that employed a portable instrument and real-time data transfer application. Secondly,to use the nucleic acid sequence data obtained from field isolates to develop a protocol compatible with rapid emergency vaccine production for NCDV.To achieve this, the isothermal PCR detection assay was applied to field isolates from suspected NCDV outbreaks on commercial poultry farms in KwaZulu-Natal, South Africa, while for the vaccine development, the NCDV matrix gene of one of the isolates was sequenced and used to design primers for the recombinant cloning of this antigen into an adenoviral vector.This‘vaccine vector’ and a control adenoviral vector were each amplified in 293T cells and then used to infect both 293T cells as a production cell line and chicken embryo fibroblasts (CEF) as a preliminary model of the target host. Western blotting confirmed the successful expression of the V5epitopetagby the control vector in both cell lines, which established the compatibility of the adenovirus vector as an appropriate carrier of the target antigen. Mass spectrometry confirmed expression of the NCDV matrix protein by the vaccine vector in both cell lines. In conclusion, the improved turnaround time from detection to the production of the vaccine antigen was under6weeks.The approach described here provides a rapid and cost-effective protocol for both the pathogen detection on-site and the production of pure vaccine antigens specific to an emerging field strain of NCDV within lower-income regions.

A high-resolution MS/MS based strategy to improve xenobiotic metabolites analysis by metabolic pathway extension searching combined with parallel reaction monitoring: Flavonoid metabolism in wound site as a case

For the analysis of xenobiotic metabolism, metabolites are commonly qualified by high-resolution mass spectrometry such as orbitrap or time-of-flight mass spectrometers, and quantified by triple-quadrupole (QQQ) mass spectrometer based multiple reaction monitoring. While this workflow shows drawback in the difficulty for instrumental parameters transfer, and QQQ provides less specificity. In this work, we constructed a high-resolution MS/MS (HR-MS/MS) based strategy to improve the discovery and quantification of unknown xenobiotic metabolites by metabolic pathway extension (MPE) searching combined with parallel reaction monitoring (PRM). Taking the flavonoid metabolism in diabetes wound S9 incubates as a test case. Firstly, MPE approach was used to screen all potential metabolites. In this step, an m/z value library of all theoretic flavonoid metabolites were constructed based on predefined flavonoid structures through 21 common xenobiotic metabolic reactions, and this library was matched with all features extracted from raw data (MS1 scan) of flavonoid-S9 co-incubate, then the matched features were exported into target list for MS2 fragmentation for structure validation. Secondly, the metabolites were relatively quantified by PRM mode based on their characteristic product ions. As a result, 131 metabolites of 9 different kinds of flavonoids in the skin and muscle were identified. To our best knowledge, this is the first report on the metabolism of flavonoids in the skin or muscle tissue. The results also validated the proposed HR-MS/MS-based strategy provided high specificity throughout both discovery and quantitation process of unknown xenobiotic metabolites without need of instrumental parameter transfer.

The problem of professional hemocontact infections in the Saratov Region

Introduction. The increase in the number of emergency situations (ES) in medical institutions in Russia actualizes the study of the state of this problem in different territories in order to optimize regional programs for the prevention of occupational diseases of medical workers, including hemocontact infections. The aim of study is to identify possible reasons for the lack of occupational morbidity of hemocontact infections in the Saratov Region. Materials and methods. To determine the frequency, types and possible causes of ES, the procedure for their registration, and the awareness of medical workers about the algorithm of actions in case of their development, 82 doctors in the specialties of obstetrician-gynecologist and surgeon (39 and 43 people, respectively) were interviewed at a multi-specialty hospital in Saratov (continuous sampling method). Results. The presence of ES in the practice of the majority of doctors surveyed (59%) was revealed, and 19% of respondents had multiple as (5 or more times). Most often, as occurs during the transfer and reception of acute surgical instruments. Among the most likely risk factors for developing as are high workload, emotional overload, and working at night. A quarter of aces do not register in the injury log, which is due to lack of time (42%) and the log itself (25%), ignorance of the need for this action (17%), fear of dismissal (8%). Conclusions. One of the main possible reasons for the lack of professional incidence of hemocontact infections is the lack of awareness of doctors about the algorithm of action in the event of an emergency at the workplace, in some cases-the lack of conditions for the implementation of this algorithm.

A novel material measure for characterising two-dimensional instrument transfer functions of areal surface topography measuring instruments

A new material measure for characterising two-dimensional (2D) instrument transfer functions (ITF) of areal surface topography measuring instruments has been designed, manufactured, calibrated and applied. Several innovative ideas are implemented in its design. Firstly, the material measure is designed with circular structure patterns. Such rotational symmetric patterns are advantageous for characterising the ITF in different angular directions, thus for characterising angular-dependent asymmetries of instruments. Secondly, different types of patterns are designed: circular chirp (CC) pattern and circular discreate grating (CDG) pattern. They represent different kinds of spatial signals applicable for characterising ITFs. A material measure consists of 25 different circular patterns with radii from 30 μm to 300 μm, and wavelengths from 0.1 μm to 150 μm. These patterns can be applied complementary and combinedly, offering high application flexibility for calibrating a variety of instruments, e.g. with different optical objectives from 5× to 100× and with different sizes of field of view (FOV). Material measures with heights of 8 nm, 16 nm and 32 nm, respectively, have been manufactured using state-of-the-art e-beam lithography technique. The feature heights are far less than λ/4, thus they are suitable for characterising the ITF of optical tools which can be approximated as linear systems. A metrological large range atomic force microscope (AFM) has been applied in the calibration of the developed material measure, showing good feature quality. The calibrated material measure has been successfully applied in research and industry.

Evaluation on The Face and Content Validity of a Soft Skills Transfer of Training Instrument

Evaluation on The Face and Content Validity of a Soft Skills Transfer of Training Instrument

String instrument acoustic transfer processing

A real-time method of string instrument acoustic transfer which includes damping is proposed. Acoustic transfer of string instruments is relevant when trying to make a non-resonant instrument, such as an electric guitar, sound more similar to an acoustic guitar. Unlike previous acoustic transfer methods which only perform equalization, this method includes damping changes by using a time-varying filter which adds frequency-dependent exponential damping. Efficient digital filters are fit to bridge admittance measurements of an acoustic guitar and used to create equalization filters as well as damping correction filters. The damping correction filters work in real-time as they are triggered by onset and pitch detection of the signal measured through an under saddle pickup to determine the intensity of the damping.