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The irregular variation of geomagnetic activity caused by the solar wind interaction with the magnetosphere/ionosphere (space weather) occurs in wide temporal and amplitude ranges. Major geomagnetic storms can induce geoelectric fields in the Earth conducting layers (through the lithosphere and down to the mantle), which may, in turn, be responsible for generating geomagnetically induced currents (GICs). The vulnerability of grounded conducting infrastructures, particularly electrical power transmission systems, to GICs, makes it important to understand the relation between the varying geomagnetic field components and the generated GICs, as well as the role of the local conductivity, i.e., geology, on the inducing process. Looking for proxies that better translate this relation is an open matter of debate.In this work, we present a comprehensive study of several possible candidates for GIC proxies. We use geomagnetic time series from the Portuguese mid-latitude Coimbra observatory (COI) to calculate geomagnetic indices considering different periods (whole-storm duration, 3-h, 1-h and 1-min), with different focuses on the field components or their derivatives, and discuss their advantages and limitations. We compare the computed indices with both GIC simulations of the Portuguese mainland high voltage power network (150, 220 and 400 kV) (Alves Ribeiro et al., 2021), and observations from a Hall effect sensor based system installed at a power transformer located in the vicinity of Coimbra. We then propose a better GIC proxy, an index obtained from geomagnetic field components filtered by convolution with a uniform conductivity Earth model filter (EGIC index), based on previous work by Marshall et al (2010,2011). We search for empirical parameters that may contain information on local conductivity effects and power network geometry.This study is funded by national funds through FCT (Portuguese Foundation for Science and Technology, I.P.), under the project MAG-GIC (PTDC/CTA-GEO/31744/2017). FCT is also acknowledged for support through projects UIDB/50019/2020-IDL, PTDC/CTA-GEF/1666/2020 (MN) and PTDC/CTA-GEO/031885/2017 (MN). CITEUC is funded by FCT (UIDB/00611/2020 and UIDP/00611/2020). We acknowledge the collaboration with REN (Redes Energéticas Nacionais).References: Alves Ribeiro J., F.J. Pinheiro, M.A. Pais, 2021. First Estimations of Geomagnetically Induced Currents in the South of Portugal. Space Weather, 19(1) Marshall R. A., C. L. Waters, M. D. Sciffer (2010). Spectral analysis of pipe‐to soil potentials with variations of the Earth’s magnetic field in the Australian region. Space Weather 8.5 Marshall, R. A., et al (2011). "A preliminary risk assessment of the Australian region power network to space weather." Space Weather 9.10

Special education teachers are essential team members in the provision of services to students with complex communication needs. Professional competencies related to augmentative and alternative communication (AAC) practices have been outlined for special education teachers as part of their professional standards. Yet, it is unclear to what extent these professionals have knowledge and skills in this area. Given existing gaps in the literature, an anonymous, web-based survey was disseminated across the United States to gather information on special education teachers’ self-reported knowledge and skills in AAC. A total of 1198 special education teachers from 46 states responded to the survey. Findings indicated that most special education teachers did not receive formal training in AAC during their teacher licensure preparation programs, resulting in low levels of self-reported knowledge and skills. Data also indicated that while influencing factors existed, special education teachers’ knowledge and skills in AAC remained minimal. Implications and recommendations for stakeholders are discussed.

Contains fulltext : 248401.pdf (Publisher’s version ) (Closed access) Laboratory procedures have been used for decades as analogues for clinical processes with the goal of improving our understanding of psychological treatments for emotional disorders and identifying strategies to make treatments more effective. This research has often focused on translation from the laboratory to the clinic. Although this approach has notable successes, it has not been seamless. There are many examples of strategies that work in the laboratory that fail to lead to improved outcomes when applied clinically. One possible reason for this gap between experimental and clinical research is a failure to focus on translation from the clinic to the laboratory. Here, we discuss potential benefits of translation from the clinic to the laboratory and provide examples of how this might be implemented. We first consider two well-established laboratory analogues (extinction and cognitive reappraisal), identify critical aspects of the related clinical procedures (exposure and cognitive restructuring) that are missing from these analogues, and propose variations to better capture the clinical process. Second, we discuss two clinical procedures that have more recently been brought into the laboratory (eye-movement desensitization and reprocessing and imagery rescripting). We conclude by highlighting potential implications of this proposed shift in focus for translational research. 30 p.

The purpose of this pilot study is to test whether the proposed threat conditioning procedures lead to adequate acquisition, extinction, and return of threat responses. Pilot data will be collected and compared across three research sites. The goal is to develop standard threat conditioning procedures that are easy to implement in other laboratories and can serve as the procedures for a future multi-site study comparing various threat extinction enhancement strategies.

A jangle fallacy is the assumption that measures are different by having different names, although they assess the same underlying construct (Gonzalez et al., in press). This is the case of opennes...

Rising atmospheric CO2 alters the ocean biochemistry in the process known as ocean acidification (OA). It influences biodiversity at different levels, including zooplankton, which is a key component of aquatic communities and plays a pivotal role in the structure and functioning of marine planktonic food webs as a major link between pelagic primary producers and planktivorous. The effect of OA on the fitness of individual zooplanktonic species has been reported by many studies mostly developed under laboratory conditions. In this context, this chapter reviews the OA effects on zooplankton and describes the potential of natural shallow-water CO2 vents as in situ laboratories. The impact on zooplankton assemblages is shown from a study in the North Atlantic (Azores islands) and the suitability of this area for future studies on marine organisms and ecosystems. Sites with naturally elevated CO2 conditions are described, including which variables and limitations must be considered. Results shown are highly relevant to improve our predictions of the responses of zooplankton to climate change stressors including OA. Future studies including long-term multigenerational exposure to multiple stressors (e.g. increased pCO2 and food shortage) are a priority to understand the adaptation capacity of common species and how the zooplankton communities will shift.

Perovskite solar cells (PSCs) are one of the most promising photovoltaic technologies. Amongst several challenges, developing and optimizing efficient electron transport layers that can be up-scaled still remains a massive task. Admittance measurements on metal-oxide-semiconductor (MOS) devices allow to better understand the optoelectronic properties of the interface between perovskite and the charge carrier transport layer. This work discloses a new pathway for a fundamental characterization of the oxide/semiconductor interface in PSCs. Inverted MOS structures, that is, glass/fluorine-doped tin oxide/tin oxide (SnO2)/perovskite are fabricated and characterized allowing to perform a comparative study on the optoelectronic characteristics of the interface between the perovskite and sputtered SnO2. Admittance measurements allow to assess the interface fixed oxide charges (Q(f)) and interface traps density (D-it), which are extremely relevant parameters that define interface properties of extraction layers. It is concluded that a 30 nm thick SnO2 layer without annealing presents an additional recombination mechanism compared to the other studied layers, and a 20 nm thick SnO2 layer without annealing presents the highest positive Q(f) values. Thus, an effective method is shown for the characterization of the charge carrier transport layer/perovskite interface using the analysis performed on perovskite-based inverted MOS devices. info:eu-repo/semantics/publishedVersion

Three experiments were conducted to evaluate direct-fed microbial (DFM) supplementation on live performance, carcass characteristics, and fecal shedding of E. coli in feedlot steers. In Exp. 1, 400 steers (BW = 348 kg) were assigned to treatments: CON = lactose carrier only, BOV = P. freudenreichii (NP24) + L. acidophilus (NP51), BOVD = P. freudenreichii (NP24) + L. acidophilus (NP51), and COMB = BOV fed for the first 101 d on feed, followed by BOVD for the final 28 d prior to harvest. In Exp. 2 (n = 1800; BW = 354 kg) and Exp. 3 (n = 112; BW = 397 kg), steers were utilized in a randomized complete block design and assigned to DFM treatments using low dose and high dose, respectively. Fecal samples were collected prior to harvest and analyzed for E. coli serogroups. In Exp. 1, DFM reduced (P E. coli O157. Prevalence of O157 was reduced by BOVD supplementation in Exp. 2 and 3 (P E. coli O157 in positive samples was reduced in both experiments where enumeration was performed (P ≤ 0.02). Weighted mean differences across the three experiments were equal to a 33% reduction in the prevalence of E. coli O157:H7 in BOVD treated cattle. A significant reduction in prevalence of O26, O45, O103, and O121 was observed in Exp. 2 (P ≤ 0.03). These results indicate that high levels of L. acidophilus (NP51) may represent an effective pre-harvest food safety intervention to reduce fecal shedding of several E. coli serogroups.

BACKGROUND Animal models and human studies have identified the potential of modafinil as a cognitive enhancing agent, independent of its effects on promoting wakefulness in sleep-deprived samples. Given that single-dose applications of other putative memory enhancers (eg, D-cycloserine, yohimbine, and methylene blue) have shown success in enhancing clinical outcomes for anxiety-related disorders, we conducted a meta-analytic review examining the potential for single-dose effects for modafinil on cognitive functioning in non-sleep-deprived adults. METHODS A total of 19 placebo-controlled trials that examined the effects of single-dose modafinil versus placebo on the cognitive domains of attention, executive functioning, memory, or processing speed were identified, allowing for the calculation of 67 cognitive domain-specific effect sizes. RESULTS The overall positive effect of modafinil over placebo across all cognitive domains was small and significant (g = 0.10; 95% confidence interval, 0.05-0.15; P < 0.001). No significant differences between cognitive domains were found. Likewise, no significant moderation was found for modafinil dose (100 mg vs 200 mg) or for the populations studied (psychiatric vs nonpsychiatric). CONCLUSIONS In conclusion, the available evidence indicates only limited potential for modafinil to act as a cognitive enhancer outside sleep-deprived populations.

Spironolactone (SP) is used to treat a variety of disparate disease states ranging from heart failure to acne through antagonism of the mineralocorticoid and androgen receptors. Although normally taken as an oral medication, recent studies have explored the topical application of SP onto the skin. However, because SP induces the proteolytic degradation of the XPB protein, which plays critical roles in DNA repair and transcription, there may be safety concerns with the use of topical SP. In this study, we show that the topical application of a high concentration of either SP or its metabolite canrenone onto human skin ex vivo lowers XPB protein levels and induces toxic responses in the epidermis. Interestingly, although SP and canrenone both inhibit cell proliferation, induce replication stress responses, and stimulate apoptotic signaling at high concentrations in cultured keratinocytes in vitro, these effects were not correlated with XPB protein loss. Thus, high concentrations of SP and canrenone likely inhibit cell proliferation and induce toxicity through additional mechanisms to XPB proteolytic degradation. This work suggests that care may need to be taken when using high concentrations of SP directly on human skin.

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When considering materials to be used as active layers in solar cells, an important required parameter is the proper knowledge of their elemental composition. It should be heavily controlled during growth in order to obtain the desired band gap and to decrease the recombination defects and then increase the solar cell electrical performance. Ion beam analytical (IBA) techniques and, in particular, particle-induced X-ray emission (PIXE) and elastic backscattering spectrometry (EBS) are quite suitable to determine the thickness and composition of such active layers. Furthermore, if these techniques are performed using a nuclear microprobe, lateral and in-depth inhomogeneities can be clearly observed from 2D maps. In many cases, composition variations can be detected from the classical 2D maps obtained from the PIXE spectra. In this work, it is shown how the in-depth variations can also be studied when considering 2D maps reconstructed from the EBS spectra. Such variations are derived from processing conditions and can be related to (i) composition, (ii) thickness, (iii) roughness, and (iv) other nontrivial issues. Examples obtained on Cu(In,Ga)Se-2-based cells are presented and discussed. Furthermore, the combination of IBA techniques such as PIXE and EBS is shown to be a competitive and alternative method to the more used and established techniques such as X-ray fluorescence for checking the average composition of the solar cell active layers or secondary ion mass spectroscopy for determination of the elemental depth profile. info:eu-repo/semantics/publishedVersion

Olivella minuta is an abundant gastropod and important consumer on beach food webs, whose feeding activity was recently demonstrated to be reduced when submerged. Our study aimed to test the interactive effects of water level and light in the activity of O. minuta. Experiments were conducted in the laboratory simulating four conditions: (1) Light, emerged (LE); (2) Dark, emerged (DE); (3) Light, immersed (LI); and (4) Dark, immersed (DI). Our results showed a significant interaction between water level and light variation. During conditions of light availability, the results corroborated our expectations and individuals were less active when immersed. However, individuals showed the highest activity when immersed during lightless conditions. This enhanced activity on dark immersed periods can be explained by optimization of feeding strategy, to benefit from the input of food resources brought by the tide. This could also be an adaptation to avoid predation by visual predators, which needs to be further evaluated. Our results show that patterns of activity of O. minuta may be susceptible to impacts of light pollution and coastal squeezing, and that the interacting effects of light and water level need to be considered in further studies on the behaviour of beach organisms. info:eu-repo/semantics/publishedVersion

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The magnetic observatory of Coimbra (IAGA code COI) measures the geomagnetic field components since 1866. These long time series were disturbed by the urban expansion in Coimbra city, causing anthropogenic perturbations in particular to the high frequency spectral band of the vertical Z component.We plan to move the observatory to another site with less magnetic disturbances. The new site is about 15 km west of Coimbra over limestone Cretaceous terrains, in São Marcos (SMC). It is far from important industrial facilities, high voltage lines, and DC electrified railways. This farm is under administration of the University of Coimbra and is surrounded by walls. Both magnetic surveys and electrical soundings were carried out at SMC. Results show low values for the magnetic gradients and resistivity profiles of relatively low to moderate values (~ 10-1000 ohm.m), typical of the studied lithological types (sandstone, marl and limestone). In this study we characterize the geomagnetic field as measured at SMC, in comparison with COI and SPT (San Pablo/Toledo) in Spain, the nearest observatory in the INTERMAGNET network of magnetic observatories.

Geomagnetically Induced Currents (GICs) are the result of rapid variations in the Earth's geomagnetic field and of the finite conductivity of the Earth. Along grounded conducting structures such as the power grids, the induced electric field drives electric currents in closed circuits. Extreme values of GICs can be a threat to the normal operation of the power system. So, there is an increasing interest in the study of the GICs’ risk and the first step to take is the numerical modelling. In order to model GICs, different factors/parameters must be considered, as the distribution of conductivity, laterally and in depth and characteristics of the different components of the network. These include the values of the different resistances in the power network, the types of transformers and also the transmission path for the GICs. Shield wires represent possible paths for GIC currents. In this study the influence of shield wires on GICs in power systems is modelled. Tests were done using realistic values for the circuit parameters provided by the Portuguese high voltage power network company (REN).The MAG-GIC (Geomagnetically induced currents in Portugal mainland) project has already produced GIC simulations for the South of Portugal. However, there are still no direct records of GICs in the electrical transmission network to validate that model. This study also encompasses the task of producing a measuring instrument to monitor GICs in the neutral of a given transformer. Such an instrument can provide for the measurement and recording of quasi-DC currents with Hall current sensors, with high resolution. It is targeted to operate remotely over a time interval of several months while being minimally invasive to the power transformer (PT). The system relies on LEM high sensitivity closed loop Hall effect current sensors and it is built over a Raspberry Pi 4 Model B platform with a high resolution digitizer (24 bits) expansion board (Waveshare AD/DA). The system also includes temperature monitoring for offset correction. Recorded data are locally stored on a database (InfluxDB) and a wifi interface allows rapid long term trend visualization through a customized dashboard (Grafana).

The separation of different sources in the geomagnetic field signal measured at satellite altitude is still an open issue. One approach to tackle this problem may be non-parametric statistical methods, such as the Principal Component Analysis (PCA). Here, PCA is applied to Virtual Observatories (VO) geomagnetic time series, computed from an enlarged Swarm dataset covering all local times and geomagnetic activity levels, from January 2014 to December 2019. For each 30-days time window, an Equivalent Source Dipole mathematical model is fitted to the data to reduce a cloud of satellite data points inside a cylinder to one single 'observation' at its axis and 500 km altitude. A VO mesh is constructed with 3394 VOs, with 2 degrees radius each and 3.5 degrees apart in latitude. We study the distribution of satellite data among the cylinders to test if any spatial or temporal sampling asymmetries can be present in the VO dataset and propagate to the PCA results. We also compare observed time series at ground level with VO time series at satellite altitude for the same latitude and longitude. After subtracting a main field model to both series, comparison of the residuals can give further insight on the dependence of external fields with altitude, with a 30-day time resolution.

One objective of this study was to determine overall prevalence of

Type 1 interferons (IFN-I) are potent innate antiviral effectors that constrain HIV-1 transmission. However, harnessing these cytokines for HIV-1 cure strategies has been hampered by an incomplete understanding of their antiviral activities at later stages of infection. Here, we characterized the IFN-I sensitivity of 500 clonally derived HIV-1 isolates from the plasma and CD4+ T cells of 26 individuals sampled longitudinally after transmission or after antiretroviral therapy (ART) and analytical treatment interruption. We determined the concentration of IFNα2 and IFNβ that reduced viral replication in vitro by 50% (IC50) and found consistent changes in the sensitivity of HIV-1 to IFN-I inhibition both across individuals and over time. Resistance of HIV-1 isolates to IFN-I was uniformly high during acute infection, decreased in all individuals in the first year after infection, was reacquired concomitant with CD4+ T cell loss, and remained elevated in individuals with accelerated disease. HIV-1 isolates obtained by viral outgrowth during suppressive ART were relatively IFN-I sensitive, resembling viruses circulating just before ART initiation. However, viruses that rebounded after treatment interruption displayed the highest degree of IFNα2 and IFNβ resistance observed at any time during the infection course. These findings indicate a dynamic interplay between host innate responses and the evolving HIV-1 quasispecies, with the relative contribution of IFN-I to HIV-1 control affected by both ART and analytical treatment interruption. Although elevated at transmission, host innate pressures are the highest during viral rebound, limiting the viruses that successfully become reactivated from latency to those that are IFN-I resistant.