bluuebunny/crossref_metadata_2025 huggingface dataset:
Pressure and Angle Sensors with Optical Fiber for Instrumentation of the PrHand Hand Prosthesis
Authors: Arco Laura De , Pontes María Jose , Segatto Marcelo Eduardo Viera , Monteiro Maxwell E. , Cifuentes Carlos A. , Díaz Camilo A. R.
Published: December 2022

The principal cause of upper limb amputations is due to traumatism. The prosthesis is an assistive device to help in the activities of daily for the amputee person. However, one of the latest reports shows that in developing countries there are around 30 million people without assistive devices. This work presents the development of two kinds of sensors for the PrHand, an upper limb prosthesis based on compliant mechanism and soft-robotics. The sensors are made with polymeric optical fiber (POF), due to their flexibility and low cost, and the working principle is based on intensity variation. The angle sensors are used for monitoring the interphalangeal joint of the fingers, and for the assessment were made cycles of closing and opening each finger. On the other hand, the force sensors are located at the tip of three fingers to track the force made over the objects. Before encoring the sensors were evaluated making five cycles of compressing and decompressing each sensor. The results show a linear behavior between the angle and the voltage variation, one most remarkable angle sensor result was with a sensibility of 0.0357 V/° and an R2 of 99 % closing and 0.0483 V/° opening. In the case of the force sensor, a polynomial relation was found between the voltage changes and the pressure over the sensor; in some cases, the relation between voltage changes and pressure could be linear but that depends on the construction of the sensor. Regarding the obtained R2 of 99 %, its sensibility was 0.0361 V/N compression and 0.0368 V/N decompression. In conclusion, was successfully developed two kinds of sensors for the instrumentation of PrHand prosthesis. It is expected to use angle and sensor variables as input in algorithms of Machine Learning to improve the detection of objects. One aspect to improve is to control in a better way the sensor construction parameters due to the considerable influence over the sensor behavior.
Model Hamiltonians of open quantum optical systems: Evolvement from hermiticity to adjoint commutativity
Authors: Zloshchastiev Konstantin G.
Published: December 2022

In the conventional quantum mechanics of conserved systems, Hamiltonian is assumed to be a Hermitian operator. However, when it comes to quantum systems in presence of dissipation and/or noise, including open quantum optical systems, the strict hermiticity requirement is nor longer necessary. In fact, it can be substantially relaxed: the non-Hermitian part of a Hamiltonian is allowed, in order to account for effects of dissipative environment, whereas its Hermitian part would be describing subsystem’s energy. Within the framework of the standard approach to dissipative phenomena based on a master equation for the reduced density operator, we propose a replacement of the hermiticity condition by a more general condition of commutativity between Hermitian and anti-Hermitian parts of a Hamiltonian. As an example, we consider a dissipative two-mode quantum system coupled to a single-mode electromagnetic wave, where we demonstrate that the adjoint-commutativity condition does simplify the parametric space of the model.
Effect of accommodation on coma at central and peripheral retina
Authors: Sapkota Kishor , Gomes Jessica , Franco Sandra
Published: December 2022

Coma is one of the most common ocular higher order aberrations and highly affects the quality of image. It is assumed that corneal aberrations are balanced by internal (lenticular) aberrations so that retinal image quality may not have great impact. However, during accommodation, the shape, position, and curvature of the crystalline lens changes which might disrupt this balance between internal and corneal aberration. This study aimed to investigate the effect of accommodation on primary coma (

C
3

−
1

and

C
3
1

) and secondary coma (

C
5

−
1

and

C
5
1

) in relaxed and accommodated eyes. Zernike coefficients were measured in 53 subjects with Hartmann-Shack aberrometer both at the central and peripheral retina up to 30° off-axis in horizontal and vertical meridians. The process was repeated with 2.50 D accommodation stimulus and comas were compared with and without accommodation. Root-mean-square of total coma was also assessed. With accommodation, vertical comas changed to more negative value and horizontal comas changed to more positive values in most of the off-axis positions. In contrast, the secondary vertical comas became less negative and secondary horizontal comas became more negative with accommodation in most of the off-axis fixations. Thus, the results showed that accommodation affects coma which depends up on position of the fixation.
Contribution to the improvement of the correlation filter method for modal analysis with a spatial light modulator
Authors: Benedicto David , Collados M. Victoria , Martín Juan C. , Mendoza-Yero Omel , Vallés Juan A. , Atencia Jesús
Published: December 2022

Modal decomposition of light is essential to study propagation properties of waveguides and photonic devices. Modal analysis can be carried out by implementing a computer generated hologram acting as a match filter in a spatial light modulator. In this work, a series of aspects to be taken into account in order to get the most out of this method are presented, aiming to provide operational procedures. First of all, the influence of the mode normalization in the complex amplitude encoding inherent noise is investigated. Then, a method for filter size adjustment based on the LP-modes symmetry is presented. Finally, a robust method to measure the phase difference between modes is proposed. These procedures are tested by wavefront reconstruction in a conventional few mode fiber.
Coupled two-core integrated waveguides modal analysis
Authors: Benedicto David , Collados M. Victoria , Martín Juan C. , Atencia Jesús , Vallés Juan A.
Published: December 2022

We present a modal analysis of coupled two-core integrated waveguides fabricated by femtosecond laser writing as a function of the core-to-core distance, illuminating position and input light wavelength. In order to do that we use the correlation filter method, implementing the computer generated holograms in a phase-only spatial light modulator. Due to the two-core waveguide symmetry, we prove it is not necessary to encode the complex amplitude in a phase-only device as long as the cores are not strongly coupled. A comparison between experimental and numerical modal weights is presented, showing that simple phase-only match filters allow the modal decomposition of two-core waveguides output beams.
Simulation and development of a prototype for high precision surface metrology
Authors: Costa Sílvia , Abreu Manuel
Published: December 2022

Optical techniques are used in many applications in the metrology field, namely for high accuracy surface profiling. Although there many techniques are available, a specific measurement methodology must be correctly chosen according to the specifications of the range of measurement, field, and surface characteristics. In this work we simulate and develop a small prototype capable of measuring surfaces of circa 10 by 10 cm with an uncertainty of 20 µm in all directions, using the astigmatic method as baseline. The aim of this paper is then to show a dedicated and optimized optical setup that allow the surface characterization of a sample surface.
Optofluidic Fabry-Perot interferometric sensor for the real-time measurement of refractive index
Authors: Leça JM , Magalhães Y , Antunes P , Pereira V , Ferreira MS
Published: December 2022

In this work, a microfluidic system combined with a fibre-optic extrinsic Fabry-Perot interferometer is proposed to measure refractive index continuously and in real time. A microfluidic platform was designed and created for this purpose through 3D printing. The Fabry-Perot cavity is an integral part of the microfluidic chip and is perpendicular to the sample flow. The light is conducted through a single mode optical fibre and the refractive index measurements were based on the optical power and wavelength shift of the reflected spectra. The developed optofluidic setup was characterised using different concentrations of glucose solutions. A sensitivity of 1102 nm/RIU was obtained when using the wavelength shift, however, when the same solution was analysed over time, the signal for wavelength shift measurements was found to be unstable. The optical power shift was correlated with the refractive index and a sensitivity of -79.6 dB/RIU was obtained, with a good linearity (r2 = 0.996). Good results were verified in terms of stability with a maximum standard deviation of 0.028 dB and a sensor resolution of 4.3×10−4 RIU. This sensor has a great potential for applications in which refractive index real-time measurements are required, such as food and beverages industry process control.
Reducing the impact of the sunlight in urban areas using asphalt mixtures with phase change materials: a review in Scopus in the last three years
Authors: Landi Salmon , Segundo Iran Rocha , Homem Natália , Sousa Jorge , Freitas Elisabete , Costa Manuel F. M. , Carneiro Joaquim
Published: December 2022

Phase change materials (PCMs) have been incorporated into asphalt concrete pavements because they can regulate the temperature by absorbing and releasing heat during physical state changes. This effect reduces temperature gradients of pavements and, consequently, increases its service life. This work presents a systematic review of recent articles published in peer-reviewed journals (available in the Scopus database) involving asphalt mixtures with PCMs and focusing on mechanical characterization. It is observed that most of the selected papers investigated the benefits of polyethylene glycol as a PCM. The most common strategy to avoid leakage during the phase transition involved using a porous material that acts as a carrier matrix for the PCMs. Generally, asphalt pavements with PCMs are systems with favourable thermal transferability, thus demonstrating higher heat absorption and dissipation rates. Finally, the asphalt mixtures containing PCMs showed lower mechanical performance than the control mixtures. However, they still satisfy the required criteria. In any case, it is expected that with the incorporation of PCMs into asphalt pavements, the social and environmental effects (Urban Heat Island) of sunlight in urban areas can be mitigated by the thermoregulation phenomena.
Autonomous Optical Tweezers: from automatic trapping to single particle analysis
Authors: Coutinho Felipe , Teixeira Joana , Rocha Vicente , Oliveira João , Jorge Pedro A. S. , Silva Nuno A.
Published: December 2022

Optical trapping is a versatile and non-invasive technique for single particle manipulation. As such, it can be widely applied in the domains of particle identification and classification and thus used as a tool for monitoring physical and chemical processes. This creates an opportunity for integrating the method seamlessly into optofluidic chips, provided it can be automatized. Yet even though OT is well established in multiple scientific domains, a full stack approach to its integration into other technological devices is still lacking. This calls for solutions in tasks such as automatic trapping and signal analysis.

In this manuscript, we describe the implementation of an algorithm seeking autonomous particle location and trapping. The methodology is based upon image-processing, allowing for particle location using real time image segmentation. A local thresholding algorithm is applied, followed by morphological techniques for closing shapes and excluding non-bounded regions - after which only the particles remain on the image. Once the centroid is identified, the stage is translated accordingly by piezo-electric actuators, followed by the laser activation. In this way, trapping is achieved, and one may proceed to analyze the forward scattered optical signal, after which a new particle inside the actuators range may be automatically trapped.

This development, when compared with existent solutions involving holographic optical tweezers, allows for similar capabilities without using a spatial light modulator, thus dramatically reducing the setup costs of autonomous OT solutions. Therefore, when combined with particle classification techniques, this method is well suited for integration into possible optofluidic chips for autonomous sensing and monitoring of biochemical samples.
Label-Free Multiplexed Analysis Using Photonic Crystal-Based Biosensors
Authors: Nifontova Galina , Fleury Fabrice , Nabiev Igor , Sukhanova Alyona
Published: December 2022

Label-free bioanalytical methods have been widely employed in biomedical research, in particular, in drug screening and discovery, diagnostics, and proteomics. Photonic crystals (PCs) represent a modern alternative to surface plasmon resonance (SPR) techniques. Imaging of PC surface modes has been demonstrated as a promising label-free approach allowing for multiplexed detection. Surface modification of PC sensors is an important stage determining the effectiveness of the analysis of biomolecule interactions. Here, we describe the results of the development of a label-free PC-based sensor, the key steps of the modification and functionalization of the PC surface with proteins, as well as the evaluation of its suitability for sensing via 2D imaging of binding events. Our data demonstrate the efficiency of the designed PC-based sensor for analysis of proteins interactions and pave the way for the engineering of a label-free biosensing platform based on PCs.
Influence of absorptive tinted filter lenses on contrast sensitivity in healthy participants under three different environmental conditions
Authors: Perez-Baladron Adrian , Salgado-Núñez Andrea , Garcia-Queiruga Jacobo , Pena-Verdeal Hugo , Yebra-Pimentel Eva
Published: December 2022

Purpose: The present study aimed to analyse the influence of absorptive tinted filter lenses on Contras Sensitivity (CS) in healthy participants under three different environmental conditions. Methods: 10 Healthy qualified volunteers who fulfilled the inclusion/exclusion criteria were recruited: refractive spherical error between +2.00 and -4.00D, refractive cylindrical error less than 1.00 D, Best Corrected Visual Acuity (BCVA) ≥ 1.0 and Low Vision Quality of Life (LVQOF) score ≥ 50. Participants were scheduled for three-session under different environmental conditions where CS was measured with a Pelli-Robson chart with and without five (ML Filters 450, 500, 511, 527 and 550) absorptive tinted filters lenses: 1) indoor, 2) outdoor on a sunny day, 3) outdoor on a rainy day. The filters were always introduced in the same order, from the higher absorption filter (ML Filter 550) to the lower (ML Filter 450). Results between filters and environmental conditions were compared. Results: There was a statistical difference in the CS values obtained with and without a filter in the measurements performed in all environmental conditions (Friedman test: all p < 0.001) with no differences in the pairwise analysis between filters (Wilcoxon test; all ≥ 0.009). There was no statistically difference in the CS values between environmental conditions without filters or with any of the filters (Friedman test: all p ≥ 0.097). Conclusions: The present study found that coloured filter lenses between 450 and 550 nm wavelength absorption had minimal impact on CS in healthy participants.
Analysis of power transfer between two multi-core fibers with long-period gratings
Authors: Sousa Liliana M. , Facão Margarida , Nogueira Rogério N. , Rocha Ana M.
Published: December 2022

Here, we numerically propose and demonstrate a technique to couple light between two multi-core fibers (MCFs) using long-period gratings (LPGs). The light is coupled from one core of the input MCF to all cores of the output MCF. For that, an LPG is inscribed in the input core of the input MCF and identical LPGs are inscribed in all cores of the output MCF. First, the light is launched into the input core of the MCF and the optical power is transferred to the cladding due to the LPG inscribed in that core. The optical power in the cladding is then transferred to the other MCF cladding by evanescent field coupling. The optical power in the cladding of the output MCF is distributed by all its cores due to the identical LPGs inscribed in them. We optimized the LPGs period, their lengths and offset distance to increase the power transfer at 1480 nm. We achieved a power transfer of 92% of the input power, distributed by all MCF cores, in 10.6 cm of length. We also studied the power transfer sensitivity to the LPGs period.
Comparison between central corneal thickness, anterior chamber depth and axial length values with and without contact lenses
Authors: Noya-Padin Veronica , Nores-Palmas Noelia , Giraldez Maria Jesus , Pena-Verdeal Hugo , Yebra-Pimentel Eva
Published: December 2022

Purpose: To compare the values of central corneal thickness (CCT), the anterior chamber depth (ACD) and the axial length (AL) on measurements performed with and without contact lenses (CL) in healthy subjects. ACD was measured with two different devices (Visionix 120+ and EchoScan US-800) and the values were also compared between them. Material and methods: 20 volunteer participants (6 men and 14 women, 24.8 ± 2.73 years) were recruited. In a single visit, participants underwent autorefraction, biometry, topography and pachymetry with the naked eye (without CL). Then, biometry and pachymetry were repeated twice wearing two different CL (Somofilcon A and Nesofilcon A) of -3.00D lens power fitted in random order. Data were compared using t-tests for related samples. Results: CCT values wearing CL were significantly higher than those obtained with the naked eye (Paired t-test; both p ≤ 0.001). On the other hand, no significant differences were found between the ACD or AL values with the naked eye versus any of the CL studied (Paired t-test, all p ≥ 0.111). The ACD values comparing Visionix120+ to EchoScan US-800 measurements were significantly different with both the naked eye and with any CL (Paired t-test; all p ≤ 0.001). Conclusion: CCT measurements cannot be performed while wearing CL. In contrast, ACD and AL measurements were not affected by the use of any CL. In addition, it was observed that ACD results from both devices are not interchangeable neither when measured with the naked eye nor using any CL.
Optical fiber sensors for monitoring cement paste carbonation
Authors: da Silva P M , Mendes J P , Coelho L C C , de Almeida J M M M
Published: December 2022

The use of concrete has been widespread in our society in housing and infrastructure, despite the environmental cost associated with its production. Its decay poses a social, economic, and environmental problem. Currently, the carbonation of cement paste is monitored through the measurement of its pH, with several optical fiber sensors (OFS) have been produced for this purpose. In the current work the focus is, also, on the carbonation monitoring of cement paste through an OFS, but not through pH measurements. Single fiber reflectance spectroscopy, previously employed to measure cement paste durability, is used to monitor the discoloration of cement paste caused by carbonation. As the carbonation front reaches the fiber tip embedded in the cement paste, the signal reflected onto the fiber increases. The accelerated carbonation of two limestone cement paste samples in an atmosphere of 100% CO2 was successfully monitored. The applicability of the sensor for operational use with ambient CO2 was confirmed through the measurement of carbonation at 3% CO2. The cross interference from water ingress and egress was also evaluated, and it didn’t hinder the measurements of carbonation. Therefore, a novel OFS capable of measuring cement paste carbonation and durability, was achieved.
A Fiber Bragg Grating based Accelerometer for Monitoring the Vibration of an Industrial Engine Prototype: A Preliminary Study
Authors: Silveira Mariana , Avellar Leticia , Cruzeiro Filipe , Macedo Leandro , Leal-Junior Arnaldo , Garcia Guilherme , Frizera Anselmo , Díaz Camilo
Published: December 2022

Monitoring the vibration of industrial engines is essential for running diagnostics that can detect faults and point out the feasibility of predictive maintenance. Therefore, this paper describes an optical accelerometer based on a fiber Bragg grating to monitor the vibration of the gearbox of an industrial engine prototype. Experimental tests were performed varying the motor’s rotation speed during normal operation. To validate the proposed system, two electronic accelerometers were attached to the motor’s gearbox and bearing. The natural frequency response of the optical accelerometer was simulated and good agreement with the experimental results was obtained (0.83% of error). The proposed sensor was able to correctly identify the operation speeds of 20, 25, 35, 40, 45 and 50 rps with a maximum error of 0.05%. The mean signal-to-noise ratio (SNR) of the optical accelerometer was 64.05% higher than the SNR of one of the electronic solutions. The experimental results show that the vibration signals have different characteristics when measured at the bearings and at the gearbox, indicating the feasibility of multi-signals analysis for fault detection.
Subwavelength structures for taper waveguides
Authors: Lourenço Paulo , Fantoni Alessandro , Costa João , Fernandes Miguel , Vieira Manuela
Published: December 2022

In Photonic Integrated Circuits (PICs) it is often necessary some sort of mismatch adaptation between waveguides of different cross-sections. There are several instances of such a designing constraint, being the vertical coupling between the PIC and an optical fibre probably the most representative of all examples. Here, the beam of electromagnetic energy inside the PIC must be inserted/extracted through/to an optical fibre. Typical core diameters are approximately 10 μm and 5 μm, for single mode optical fibres operating in the near infrared and visible wavelengths, respectively. On the other hand, the optical interconnects linking individual structures in PICs are usually single mode waveguides, 400 to 500 nm wide and a few hundreds of nanometres thick. This presents a bidimensional mismatch between the optical fibre and the single mode waveguide within the PIC, that requires both lateral and longitudinal beam expansions. In this work, we have approached the lateral expansion of the fundamental mode propagating in a single mode waveguide, at the operating wavelength of 1550 nm and being coupled out into an optical fibre, through a grating structure 14.27 μm wide. To this end, we have designed and simulated a subwavelength metamaterial planar structure, which is able to expand laterally the fundamental mode’s profile from 450 nm to 14.27 μm, within 11.1 μm. Furthermore, we will be presenting the results obtained when comparing this structure with several linear inverted taper waveguides, regarding coupling and propagation efficiencies. Namely, we compared the coupling efficiencies of the modes propagating in an 100 μm long waveguide, when being excited by the analytically calculated fundamental mode and the fields obtained at the end of the designed structure. The results obtained for the designed structure 11.1 μm long and the calculated fundamental mode showed a coupling efficiency of -1.53 dB and -1.20 dB, respectively.
Towards real-time identification of trapped particles with UMAP-based classifiers
Authors: Teixeira Joana , Rocha Vicente , Oliveira João , Jorge Pedro A. S. , Silva Nuno A.
Published: December 2022

Optical trapping provides a way to isolate, manipulate, and probe a wide range of microscopic particles. Moreover, as particle dynamics are strongly affected by their shape and composition, optical tweezers can also be used to identify and classify particles, paving the way for multiple applications such as intelligent microfluidic devices for personalized medicine purposes, or integrated sensing for bioengineering. In this work, we explore the possibility of using properties of the forward scattered radiation of the optical trapping beam to analyze properties of the trapped specimen and deploy an autonomous classification algorithm. For this purpose, we process the signal in the Fourier domain and apply a dimensionality reduction technique using UMAP algorithms, before using the reduced number of features to feed standard machine learning algorithms such as K-nearest neighbors or random forests. Using a stratified 5-fold cross-validation procedure, our results show that the implemented classification strategy allows the identification of particle material with accuracies up to 80%, demonstrating the potential of using signal processing techniques to probe properties of optical trapped particles based on the forward scattered light. Furthermore, preliminary results of an autonomous implementation in a standard experimental optical tweezers setup show similar differentiation capabilities for real-time applications, thus opening some opportunities towards technological applications such as intelligent microfluidic devices and solutions for biochemical and biophysical sensing.
Characterization of Light Diffraction by a Digital Micromirror Device
Authors: Pereira C , Abreu M , Cabral A , Rebordão J M
Published: December 2022

A Digital Micromirror Device (DMD) is a technology developed by Texas Instruments, that consists in a two-dimensional array of micromirrors, which can be individually tilted between two positions. It has been used as a digital video and image processing solution,
commonly found in Digital Light Processing (DLP) video projectors. Over the years, DMDs have become popular in different fields: industrial, automotive, medical, government and home user solutions. In the astronomy field, it has been also considered in on-ground space instrumentation and it has been proposed for the development of some astrophysical space
instruments. In order to evaluate the actual impact of such device in the instrument optical design, it is important to know how the light behaves when it interacts with a DMD, namely in what regards to the diffraction process when a light beam is reflected by a periodic array of
micromirrors. In this study we describe how we simulate the diffraction patterns produced by a periodic array of micromirrors, for coherent and incoherent sources of light. The results from simulations are verified against laboratory experiments, described also in this study.
Evaluation of the orientation impact on thermal behavior of cylindrical Li-ion batteries in different cycling conditions using fiber Bragg grating sensors
Authors: Matuck L , Pinto J L , Marques C , Nascimento M
Published: December 2022

In this work, optical fiber Bragg grating (FBG) sensors were used to evaluate the thermal performance of an 18650 Li-ion battery (LiB) operating under normal and abusive conditions while positioned in horizontal and vertical orientations. In total, three FBG sensors were used to track in real-time the temperature variation of the cathode, middle, and anode of the LiB. Tests for each orientation were performed, where each of them consisted of two cycles: the first one with normal charge/discharge conditions, operating between 2.75 V and 4.20 V, and another in abusive conditions, operating between 2.00 V and 4.95 V. The battery was submitted to constant current charge and discharge steps, with rest intervals between each operation. The results suggest that, in general, the temperature variation while operation in vertical orientation is lower when compared to the horizontal one, mainly in the anode, while the LiB is submitted to the abusive charge procedure, where the temperature variation difference achieved 3.4 ± 0.2 °C. In addition, the FBG sensors were able to track in real-time the temperature variation of three different locations of the battery simultaneously. The temperature variation registered for each sensor is shown and discussed.
Multimodal approach to mineral identification: merging Laser-induced breakdown spectroscopy with Hyperspectral imaging
Authors: Lopes Tomás , Cavaco Rafael , Rodrigues Pedro , Ferreira Jorge , Capela Diana , Ferreira Miguel F. S. , Jorge Pedro A. S. , Silva Nuno A.
Published: December 2022

While laser-induced breakdown spectroscopy is often used as a standalone technique, recent years saw an increasing interest in their combination with additional techniques towards multimodal sensing solutions capable of enhancing the capabilities of this technological solution. In this work, we try to identify possible synergies that arise from merging the analysis of laser-induced breakdown spectroscopy with that from a hyperspectral scanning of the sample, comparing it with the performance of standalone solutions. Having investigated the multimodal approach for a case study involving the identification of lithium minerals, our preliminary results demonstrate that while both solutions can provide reasonable results for qualitative mineral identification, they feature advantages and disadvantages that shall be taken into further consideration. Nevertheless, when working in collaboration, the results enclosed suggest that an integrated tandem solution can be an interesting tool for material analysis for research and industrial applications, combining the best of both instruments.
Microdosimetry-based quality factors for ISO reference photon and beta sources: TOPAS Monte Carlo study
Authors: Chattaraj Arghya , Palani Selvam T. , Shrivastava Vandana , Pradhan S.M.
Published: December 2022

In radiological protection, personnel dosimeters are
calibrated in terms of operational quantities such as H
p
(10)
and H
p
(0.07) against ISO reference photon and beta sources,
respectively. H
p
(10) and H
p
(0.07) are defined at 1 cm and
0.07 μm depths in the ICRU-4 element tissue phantom. In
present study, mean quality factor Q̅ is calculated at
these depths using the TOPAS-based microdosimetric distributions at
1 μm site size and FLUKA-based Linear Energy Transfer (LET)
dependent Q̅. The sources simulated are ISO reference
narrow series X-rays, 137Cs and 147Pm, 85Kr,
90Sr/90Y and 106Ru/106Rh beta sources. Using the
calculated microdosimetric distributions, Q̅ is
calculated based on ICRP60 and ICRU40 recommendations, Keller-Hahn
(KH) approximation, Microdosimetric Kinetic Model (MKM), Clonogenic
Survival and Theory of Dual Radiation Action (TDRA). The study
includes FLUKA-based Q̅ values calculated using Q(L)
vs L relationship as per ICRP Report 60. The MKM, Clonogenic
Survival-based RBE, ICRU40, TDRA and KH-based Q values
of all the investigated sources are about unity. Depending on the
source, microdosimetry-based Q̅ values using ICRP60
recommendations show significant difference from that calculated
using other models. Q̅ values of 137Cs are unity,
independent of the models.
Human and animal movements combine with snow to increase moose-vehicle collisions in winter
Authors: Cunningham Calum X , Liston Glen E , Reinking Adele K , Boelman Natalie T , Brinkman Todd J , Joly Kyle , Hebblewhite Mark , Boutin Stan , Czetwertynski Sophie , Sielecki Leonard E , Prugh Laura R
Published: December 2022

Wildlife-vehicle collisions imperil humans, wildlife, and property. Collisions with moose (Alces alces) are especially consequential and there are indications they may increase during severe winters. We tested hypotheses regarding the influence of moose movements and vehicular traffic patterns on collision risk. We first modeled daily snow depth and accumulation across 5.6 million km2 of the North American Arctic-Boreal region. Next, we analyzed the movements and road use of 113 GPS-collared moose in response to snow depth. Finally, we examined the influence of these snow properties on vehicular traffic and 7680 moose-vehicle collisions. As winter progressed and the snowpack deepened in each study area, GPS-collared moose migrated to lower elevations, leading them into areas with shallower snow but higher road densities. This elevational migration corresponded with a higher probability of road-use by moose (by up to ten-fold) in winter than in summer. Corresponding to these patterns, moose-vehicle collisions were 2.4–5.7 times more frequent from December through February (compared to early summer). Collision risk was highest when and where snow depth was less than 120 cm, indicating that migration into areas with shallower snow increased collision risk in those areas. Most (82%) moose-vehicle collisions occurred after dark. This pattern was strongest during winter, when nighttime traffic volumes were eight times higher than summer due to longer nights. Overall, our findings suggest that concurrent seasonal changes in human and wildlife behavior increase the frequency of moose-vehicle collisions during winter. Snow depth influences collisions primarily through its impacts on moose movement, while strong seasonal changes in daylight hours cause an increase in nighttime traffic that further contributes to risk. This information may help predict times and places where risk of moose-vehicle collisions are highest and to develop seasonally dynamic mitigation strategies.
Consumption-based view on national and regional per capita carbon footprint trajectories and planetary pressures-adjusted human development
Authors: Ala-Mantila Sanna , Heinonen Jukka , Clarke Jack , Ottelin Juudit
Published: December 2022

Current national greenhouse gas (GHG) emissions accounts and mitigation targets are mostly based on territorial GHG accounting. While several analyses present future trajectories describing how nations could achieve emissions targets, there are relatively few analyses from the consumption-based perspective. Simultaneously, there is a broad literature on consumption-based carbon footprints of individuals and regions, but without connection to the remaining carbon budgets and associated mitigation pathways, nor to the current levels of human development. This study contributes to these debates by downscaling the 1.5-degree target to an individual scale for 152 countries, following the Intergovernmental Panel on Climate Change (IPCC’s) shared socioeconomic pathway (SSP1-1.9) pathway. We compare the calculated limits to current carbon footprints and show how the individual carbon budget can be operationalized on a national and regional level using Africa, Europe, and the USA as examples. We show that while GHG emissions in Europe and the USA greatly exceed the budget, in Africa the budget allows even growth in the short and medium term, and the emission cuts later if the remaining carbon budget is equally allocated regardless of the historic emissions. Finally, we modify the planetary pressures adjusted human development index (HDI) with consumption-based carbon footprints to highlight how different accounting principles underscore the uneven development between nations. We find that the average carbon footprint of many highly developed nations is as much as seven times the climate-sustainable limit. Furthermore, these same nations perform poorly when measuring their development level with the consumption-based emissions updated planetary pressures HDI. However, in the majority of nations (80% of the global population) the average carbon footprint is near or below the climate-sustainable level, but not in any of the top HDI countries. Our findings highlight that stronger policy and swift changes are needed to bring the carbon footprints of the residents of affluent countries to a climate-sustainable level.
Preparation and characterization of titanium dioxide using PLD at various energy of pulsed laser
Authors: Mohammed Rami S , Fakhri Makram A
Published: December 2022

Because of its distinctive optical and electrical characteristics, titanium dioxide (TiO2) thin films are one of the significant and promising semiconductor materials for environmental and energy applications. The effect of the laser pulse energy of Nd:YAG on the properties of TiO2 thin film grown on silicon and quartz substrates using the laser pulse deposition technique by the crystal structure, surface area, crystalline structure, average particle size, and porosity were summarised. The nano-thin film with the optimum condition has been prepared with a pulse laser energy of 900 mJ. The optical properties have been investigated using UV–vis spectrophotometer, morphological properties have been studied using atomic force microscopy and field emission scanning electron microscopy, and structural properties have been examined using x-ray diffractometer and Raman spectrometer. The tests and measurements have shown a crystalline structure, and the distribution of the grains was regular in the film. Raman spectroscopy showed two diffraction peaks corresponding to anatase Eg and rutile Eg. This observation is typically used in dye-sensitised solar cells, separation sensor devices, and more.
In committee
Authors: Ritchie Donald A.
Published: December 2022

Committees of Congress are at the heart of the legislative process with the major issues of government divided between them. “In committee” explains how legislation starts with a bill that is then assigned to the appropriate committee or subcommittee. Securing a place on a committee is a key step for all members of Congress. Committees also have permanent staff and call expert witnesses in the process of framing legislation. The importance of the Appropriations Committee, which controls the budget, and the place of the conference committee that brings together both House and Senate to reach compromises on disagreements are also examined.
The Capitol complex
Authors: Ritchie Donald A.
Published: December 2022

“The Capitol complex” describes the multitude of office buildings linked by tunnels that have steadily expanded to accommodate the extended community of senators, representatives, staff, journalists, and lobbyists, as well as the many visitors to the Capitol. How the different parts of this community have developed over history and the infrastructure to accommodate them has grown is traced. The relationship between members and their staffs is examined, while the ever-expanding role of lobbyists and journalists is scrutinized. So too is the Capitol’s efforts to remain accessible to the huge numbers of the American public who visit the Capitol each year.
Adverse effects of nonsteroidal anti-inflammatory drugs in critically ill patients: A scoping review
Authors: Martin Jennifer R , Yu Madeline , Erstad Brian L
Published: December 2022

Purpose

Nonsteroidal anti-inflammatory drugs (NSAIDs) are often recommended as opioid-sparing agents. The objective of this scoping review was to conduct a thorough search of the current literature to determine whether in adult critically ill patients there is an association between exposure to NSAIDs vs no NSAIDs and the subsequent development of serious adverse events, particularly gastrointestinal bleeding and acute kidney injury (AKI).

Methods

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for Scoping Reviews was utilized as a guideline for reporting. Searches were performed in PubMed (National Library of Medicine), Cochrane Library (Wiley), EMBASE (Elsevier), Stat!Ref (Teton), and Access Pharmacy (McGraw Hill) for articles published from January 2016 to August 2022.

Results

Of the 3,062 citations and titles identified in the search, 2,737 titles remained after removal of duplicates, 2,588 were excluded at title and abstract screening, and 149 articles remained for full-text review. None of the studies involved heterogeneous groups of critically ill patients in nonspecialty intensive care unit settings. Most studies evaluated were conducted in the perioperative setting and had limited adverse events reporting, particularly with respect to serious NSAID-related adverse effects of concern in critically ill patients.

Conclusion

In published studies primarily involving perioperative patients, there is insufficient detail concerning the definitions and reporting of NSAID-related serious adverse events such as bleeding and AKI. These events are of particular concern in heterogeneous critically ill patient populations predisposed to such complications. In most (if not all) critically ill patients, sustained dosing of NSAIDs should be avoided regardless of COX-1 selectivity due to the paucity of safety data.
Quantitative MRI maps of human neocortex explored using cell type-specific gene expression analysis
Authors: Edwards Luke J , McColgan Peter , Helbling Saskia , Zarkali Angeliki , Vaculčiaková Lenka , Pine Kerrin J , Dick Fred , Weiskopf Nikolaus
Published: December 2022

Quantitative magnetic resonance imaging (qMRI) allows extraction of reproducible and robust parameter maps. However, the connection to underlying biological substrates remains murky, especially in the complex, densely packed cortex. We investigated associations in human neocortex between qMRI parameters and neocortical cell types by comparing the spatial distribution of the qMRI parameters longitudinal relaxation rate (${R_{1}}$), effective transverse relaxation rate (${R_{2}}^{\ast }$), and magnetization transfer saturation (MTsat) to gene expression from the Allen Human Brain Atlas, then combining this with lists of genes enriched in specific cell types found in the human brain. As qMRI parameters are magnetic field strength-dependent, the analysis was performed on MRI data at 3T and 7T. All qMRI parameters significantly covaried with genes enriched in GABA- and glutamatergic neurons, i.e. they were associated with cytoarchitecture. The qMRI parameters also significantly covaried with the distribution of genes enriched in astrocytes (${R_{2}}^{\ast }$ at 3T, ${R_{1}}$ at 7T), endothelial cells (${R_{1}}$ and MTsat at 3T), microglia (${R_{1}}$ and MTsat at 3T, ${R_{1}}$ at 7T), and oligodendrocytes and oligodendrocyte precursor cells (${R_{1}}$ at 7T). These results advance the potential use of qMRI parameters as biomarkers for specific cell types.
Development of the neural correlates of recollection
Authors: Sweatman Hilary , Lewis-de los Angeles C Paula , Zhang Jiahe , de los Angeles Carlo , Ofen Noa , Gabrieli John D E , Chai Xiaoqian J
Published: December 2022

Recollection of past events has been associated with the core recollection network comprising the posterior medial temporal lobe and parietal regions, as well as the medial prefrontal cortex (mPFC). The development of the brain basis for recollection is understudied. In a sample of adults (n = 22; 18–25 years) and children (n = 23; 9–13 years), the present study aimed to address this knowledge gap using a cued recall paradigm, known to elicit recollection experience. Successful recall was associated with activations in regions of the core recollection network and frontoparietal network. Adults exhibited greater successful recall activations compared with children in the precuneus and right angular gyrus. In contrast, similar levels of successful recall activations were observed in both age groups in the mPFC. Group differences were also seen in the hippocampus and lateral frontal regions. These findings suggest that the engagement of the mPFC in episodic retrieval may be relatively early maturing, whereas the contribution to episodic retrieval of more posterior regions such as the precuneus and angular gyrus undergoes more protracted maturation.
Exposure to Thioguanine During 117 Pregnancies in Women With Inflammatory Bowel Disease
Authors: Crouwel Femke , Simsek Melek , de Boer Marjon A , Mulder Chris J J , van Andel Emma M , Creemers Rob H , van Asseldonk Dirk P , van Bodegraven Ad A , Horjus Carmen S , Visschedijk Marijn C , Weusthuis Angelique L M , Seinen Margien L , Jharap Bindia , van Schaik Fiona D M , Ahmad Ishfaq , Boekema Paul J , Tack Greetje J , Wormmeester Louktje , Lutgens Maurice W M D , van Boeckel Petra G A , Gilissen Lennard P L , Kerkhof Marjon , Russel Maurice G V M , Hoentjen Frank , Bartelink Maartje E , Kuijvenhoven Johan P , Maljaars Jeroen W J , van Dop Willemijn A , Wonders Janneke , van der Voorn Michael M P J A , Buiter Hans J C , de Boer Nanne K
Published: December 2022

Background

Safety of thioguanine in pregnant patients with inflammatory bowel disease [IBD] is sparsely recorded. This study was aimed to document the safety of thioguanine during pregnancy and birth.

Methods

In this multicentre case series, IBD patients treated with thioguanine during pregnancy were included. Data regarding disease and medication history, pregnancy course, obstetric complications, and neonatal outcomes were collected.

Results

Data on 117 thioguanine-exposed pregnancies in 99 women were collected. Most [78%] had Crohn’s disease and the mean age at delivery was 31 years. In 18 pregnancies [15%], IBD flared. Obstetric and infectious complications were seen in 15% [n = 17] and 7% [n = 8] of pregnancies, respectively. Ten pregnancies [8.5%] resulted in a first trimester miscarriage, one in a stillbirth at 22 weeks of gestational age and one in an induced abortion due to trisomy 21. In total, 109 neonates were born from 101 singleton pregnancies and four twin pregnancies. One child was born with a congenital abnormality [cleft palate]. In the singleton pregnancies, 10 children were born prematurely and 10 were born small for gestational age. Screening for myelosuppresion was performed in 16 neonates [14.7%]; two had anaemia in umbilical cord blood. All outcomes were comparable to either the general Dutch population or to data from three Dutch cohort studies on the use of conventional thiopurines in pregnant IBD patients.

Conclusion

In this large case series, the use of thioguanine during pregnancy is not associated in excess with adverse maternal or neonatal outcomes.
The dental and craniofacial characteristics among children with obstructive sleep apnoea: a systematic review and meta-analysis
Authors: Liu Yanxiaoxue , Zhao Tingting , Ngan Peter , Qin Danchen , Hua Fang , He Hong
Published: December 2022

Background

Paediatric obstructive sleep apnoea (OSA) is a sleep breathing disorder which may have dramatic effects on childhood behaviour, neurodevelopment, metabolism, and overall health in children. Malocclusion and craniofacial morphology may be related to paediatric OSA, and therefore provide information for clinicians to recognize, evaluate and treat patients with this sleeping disorder.

Objective

The aim of this systematic review was to summarize evidence regarding the association between paediatric OSA and children’s dental and craniofacial characteristics.

Search methods

PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched from inception to 1 June 2022.

Selection criteria

Cross-sectional studies, comparing dental or craniofacial characteristics using clinical dental examinations or radiographic findings between OSA children (less than 18 year, diagnosed with overnight polysomnography) and healthy children, were included.

Data collection and analysis

The Joanna Briggs Institute Critical Appraisal Checklist for Analytical Cross-Sectional Studies was used to assess the quality of included studies. RevMan software was used for performing the Meta-analyses.

Results

Sixteen studies were included. Meta-analyses showed that the overjet (MD = 0.86, 95% CI: 0.20 to 1.51; P = 0.01), the saggital skeletal jaw discrepancy (ANB; MD = 1.78, 95% CI: 1.04 to 2.52; P < 0.00001) and mandibular plane angle (FH-MP; MD = 3.65, 95% CI: 2.45 to 4.85; P < 0.00001) were greater in OSA-affected children. In contrast, the upper molar arch width (upper first deciduous molar width; MD = –1.86, 95% CI: –3.52 to –0.20; P = 0.03), (Upper second deciduous molar width; MD = –1.06, 95% CI: –1.88 to –0.24; P = 0.01), SNB (MD = –2.10, 95% CI: –3.11 to –1.09; P < 0.0001), and maxillary length (ANS-PNS; MD = –1.62, 95% CI: –2.66 to –0.58; P = 0.002) were smaller in the OSA group.

Conclusions

This review shows that OSA-affected children tend to present with mandibular retroposition or retrognathia, increased mandibular plane angle and excess anterior overjet. However, these findings need to be viewed with caution as the corresponding differences may not be significant clinically.

Registration

PROSPERO (CRD42020162274)