Hyposmia and substantia nigra hyperechogenicity (SN+) are characteristic markers of Parkinson's disease (PD), although their diagnostic value in isolation may be limited. We evaluated the combined ...prevalence of both disorders in patients diagnosed with PD and assessed their diagnostic yield compared to a sample with essential tremor (ET) and another group of healthy subjects.
Patients diagnosed with PD and ET and treated in our outpatient clinic were enrolled. Olfaction was assessed using the "Sniffin' Sticks" odour identification test (SS-12) and hyperechogenicity of the substantia nigra (SN+) was assessed by transcranial duplex ultrasound.
A total of 98 subjects were analysed, comprising 30 with PD, 21 with ET, and 47 controls. The respective prevalence rates of hyposmia (SS-12 < 8) and SN+ (area > .24cm(2)) were 70% and 83.3% in PD, 33.3% and 9.5% in ET, and 17% and 10.6% in controls. Both markers were present in 63% of patients with PD, none of the patients with ET, and only 2 of the controls.
Combined use of substantia nigra sonography and olfactory testing with SS-12, two rapid, safe, and accessible tests, was more specific than each isolated marker for distinguishing patients with PD from patients with ET and control subjects. Since both markers have been described in very early phases of PD, combined use may be helpful in providing early diagnosis of PD.
From a new gravity data set that covers homogeneously the whole surface of Gran Canaria (Canary Islands, Spain) and marine gravity data in the nearest offshore, we have obtained a Bouguer anomaly ...gravity map of the island which improves the previous ones. Using these gravity anomalies, we have applied a gravity inversion approach to investigate the structures beneath the surface of Gran Canaria Island and derive a 3D gravity sources model. The geometry of structures with anomalous density values is constrained up to a depth of approximately 20,000 m below the sea level. The interpretation of the density model identified structures related to the different volcanic stages of Gran Canaria. Several deep‐rooted high‐density structures represent the intrusive bodies emplaced in the early formation of Gran Canaria and the magma plumbing system of the Miocene volcanic edifices. A low‐density body in the center of the island may be associated with the syenitic core of the felsic central volcanic edifice (Tejeda Caldera). Shallow low‐density structures identified fractures which acted as feeder dikes of monogenetic volcanoes during the rejuvenated stage. Finally, the NW‐SE rift, which is the most important volcano‐tectonic structure of Gran Canaria, has a characteristic gravimetric signature and represents a long‐lived extensional fracture zone that has controlled the volcanic activity at least since the Miocene.
Plain Language Summary
We present a study of Gran Canaria Island (Canarian Archipelago, Spain) that provides a new model of the sources of the gravity field through the inversion of a new land and marine gravity data set. This model identifies several high‐density crustal structures that correspond to the intrusive bodies emplaced in the early formation of Gran Canaria. A low‐density body revealed in the center of the island is associated with the central volcanic edifice, the Tejeda Caldera. Other structures unveiled in the model are related to different volcanic stages and volcano‐tectonic features of Gran Canaria Island.
Key Points
We have obtained a gravity anomaly map for Gran Canaria from a new data set, which was inverted to model the shallow subsurface structures
The interpretation of the gravity model improves our knowledge about subsurface structures and the volcanic evolution of this island
To study the deep structure of El Hierro Island, Canarian Archipelago, we have used a microseismic sounding method (MSM) based on the fact that heterogeneities of the Earth’s crust disturb the ...spectrum of the low-frequency microseismic field in their vicinity. So, at the Earth’s surface, the spectral amplitudes of definite frequency
f
above the high-velocity heterogeneities are decreasing, and above the low-velocity ones they are increasing. Moreover, the frequency
f
is connected with the depth of a heterogeneity
H
and the velocity of the fundamental mode of Rayleigh waves
V
R
(
f
) through the relation
H
≈ 0.4
V
R
(
f
)/
f.
From these relations, the MSM lets us model the subsurface structure in a 3D context by inverting the amplitude-frequency spatial distribution of the microseismic field of low frequency. The validity of the method is shown through of numerical simulations and previous applications with known or verified solutions. This MSM is now used to invert the microseismic data registered in El Hierro Island. The obtained subsurface model reveals two large intrusive bodies beneath the island. Joint interpretation of microseismic and gravimetric data and their comparison with the available geological studies relate the central-eastern intrusive body to the early stage of the island formation. With respect to the western intrusive body, at the depths of 15–25 km, an area with lowest seismic velocities is identified, where we suggest that a modern magmatic reservoir is located. This reservoir could be associated with the recent submarine eruption in October 2011 and the accompanying seismic swarm, which started in July 2011. Several correlations between the shallowest structures identified by the gravity and MSM approaches are also found. Besides the numerical simulation and previous studies of this method, the correlation between gravity results, the MSM model, the geological information and the possible explanation of the features of the seismic swarm through the model obtained offer us a valid proof about the plausibility of the subsurface structures identified from MSM.
Resumen Introducción La hiposmia y la hiperecogenicidad de la sustancia negra (SN+) son marcadores característicos de la enfermedad de Parkinson (EP), aunque su valor diagnóstico de forma aislada ...puede ser limitado. Se evalúa la prevalencia combinada de ambos marcadores en pacientes diagnosticados de enfermedad de Parkinson (EP) y su rentabilidad diagnóstica frente a una muestra con temblor esencial (TE) y otra de sujetos sanos. Métodos Se incluyó a pacientes con diagnóstico de EP y TE procedentes de nuestra consulta externa. La olfación se evaluó con el test de identificación de olores Sniffin Sticks test (SS-12) y la evaluación de la sustancia negra mediante dúplex transcraneal. Resultados Se evaluó a 98 individuos, 30 con diagnóstico de EP, 21 con TE y 47 controles. Las prevalencias de hiposmia (SS-12 < 8) e hiperecogenicidad de SN (área > 0,24 cm2 ) fueron del 70 y el 83,3% en EP, el 33,3 y el 9,5% en TE y el 17 y el 10,6% en los controles, respectivamente. La combinación de ambos marcadores estaba presente en el 63% de los pacientes con EP y en ninguno de los pacientes con TE y solo en 2 de los controles. Conclusiones La evaluación combinada de la evaluación olfativa mediante el SS-12 y de la sustancia negra mediante ecografía, 2 test rápidos, inocuos y accesibles, mejora la especificidad aislada que cada marcador tiene en el diagnóstico de la EP frente a pacientes con TE o controles. Dado que ambos marcadores se han descrito en fases muy precoces de la EP, su aplicación podría ayudarnos en su diagnóstico precoz.
A new two-loop control scheme for voltage-mode control (VMC) of dc-dc switching converters is presented. The proposed method adds a high-gain robust loop with two controllers to the conventional VMC ...loop, achieving an analog "adaptive" loop in which the "equivalent voltage regulator" varies with the changing power stage parameters given as follows: 1) input voltage; 2) load; and 3) component tolerances. The loop significantly improves the disturbance rejection of the control system, i.e., closed-loop output impedance and audiosusceptibility while preserving the stability and the loop gain crossover frequency to a significant extent. Both the small-signal analysis and the experimental results carried out on a buck converter demonstrate the superiority of the proposed scheme with respect to the conventional single loop.
This paper proposes a new robust control technique for single-phase boost high-power-factor rectifiers. The proposed circuit significantly improves the dynamic response of the converter to load steps ...without the need of a high crossover frequency of the voltage loop, so that a low distortion of the input current is easily achieved. A 250-W power-factor-correction rectifier with the proposed control scheme has been designed and implemented, validating the concept both analytically and experimentally.
El Hierro is the youngest and westernmost island of the Canarian Archipelago. Due to its singular and interesting characteristics, with extensive landsliding, studying its crustal structure can ...provide very useful information about its origin and evolution. With this aim, we use the gravity inversion methodology obtaining a crustal model of mass distribution. We performed a gravity survey of the entire island, completing the gravity anomaly map of this area with marine data from the United States Geological Survey. The calculated Bouguer gravity anomaly map was studied using a covariance analysis and the least squares technique. To obtain crustal information from these data, we used a 3D gravity inversion based on genetic algorithms (GA). Thus, our inversion technique aims to determine the geometry of the sources of the observed gravity field, upon a prismatic partition of the subsoil volume, and adopting a priori density contrast values. The results of this gravity study of El Hierro Island show the correlation of several volcanic structures with the distribution of the gravity field sources. The characteristic triple rift system of the island is associated with low-density areas, and the older volcanic stages with high-density structures. We also found differences among the structures related to the several landslides, which helped the island takes shape.
Abstract
Study question
Are outcomes of day 5 (D5) blastocysts better than day 6 (D6) blastocysts in a PGT-A program?
Summary answer
Outcomes of day 5 embryos show more blastocysts, better quality, ...more euploidy due to better quality and higher implantation on same quality than day 6.
What is known already
Human embryos optimally reach the blastocyst stage after five days of culture, but some have a slower development. The superiority of day 5 blastocysts compared to day 6 blastocysts in fresh cycle transfers was previously demonstrated and attributed mainly to endometrial asynchrony.
Data from frozen blastocysts transfers showed conflicting results, some studies have announced higher pregnancy rates after day 5 transfer compared with day 6 transfer, while others have shown equivalent outcomes.
However, none of these studies have compared outcomes between same quality and euploid day 5 (D5) frozen blastocysts versus those frozen on day 6 (D6).
Study design, size, duration
Retrospective observational study performed in a private centre between May 2017 and December 2022.
The study includes the data analysis of 5599 D5 and D6 blastocysts undergoing PGT-A obtained from 819 patients following 1295 PGS cycles. 948 euploid blastocysts with known implantation outcome were transferred in 789 frozen embryo transfers.
Blastocyst morphology was scored in 3 groups: A: excellent (AA, AB, BA), B: good (BB), C: average and poor-quality embryos (BC, CB, CC). (Gardner-Schoolcraft classification)
Participants/materials, setting, methods
PGT-A with NGS technology was offered to patients of advanced maternal age and/or with repeated IVF failures. Trophectoderm biopsies were performed on D5 and/or D6 embryos, with laser assistance. (Navilase, OCTAX)
We compared both populations (D5 and D6) in terms of number of blastocysts achieved and distribution of embryo quality of each population. As primary outcome, same-quality group results of euploid rate and implantation were compared according to the day of blastocyst development (D5 and D6).
Main results and the role of chance
Vast majority of the blastocysts were biopsied on D5 (71.8%, n = 4017) versus (28.2%, n = 1582) biopsied on D6.
The proportion of three quality-categories of blastocysts according to D5/D6 is uneven. Quality A = 18.6% vs 3,5%. Quality B = 72,4% vs 59,6%. Quality C = 9,0% vs 36,9%, respectively, showing significative differences between D5/D6 (Chi^2 p-values of 3 groups< 0.001), concluding that overall D5 quality is better than D6.
Overall euploidy rate on D5 population versus D6 was 31,3% vs 23,3% (p value <0.001), showing significant difference in favour of D5. But layering on 3 quality categories on D5/D6, the euploidy rate was 44,7% vs 51,8% for quality A, 29,6% vs 26,6% for quality B and 17,6% vs 14,9% for quality C, respectively, showing no significative differences D5/D6 (Chi^2 p-values: A = 0,331; B = 0,067; C = 0,280). Euploidy is not D5/D6 dependant but quality dependant.
Overall implantation on D5 (65,9%) is higher than D6 (40,4%) (p value <0.001). Layering again, on D5 the implantation was 75,0% vs 66,7% for quality A, 63,8% vs 46,4% for quality B and 35,3% vs 26,3% for quality C, respectively. Despite implantation being higher on D5 on all three groups only group B shows D5/D6 significative differences. (Chi^2 p-values: A = 0,651; B < 0.001; C = 0,360). Implantation is embryo quality and D5/D6 dependant.
Limitations, reasons for caution
The study is limited by its retrospective nature and the low number of grade A D6-euploid blastocysts available to transfer. Additionally, it is common to transfer more than one grade C quality embryo to increase the chances of pregnancy, losing implantation track of these type.
Wider implications of the findings
It was uncontested that D5 blastocysts had better reproductive potential, but we managed to quantify this potential according to euploidy and implantation rates based on embryo quality, which remains the most important predictive biomarker for selecting the best embryo to transfer and reducing the time to achieve a pregnancy.
Trial registration number
not applicable
BACKGROUND Pigeon breeder's disease is an extrinsic allergic alveolitis in the lungs of sensitised people, caused by hypersensitivity reactions to inhaled pigeon antigens. Antigens from different ...sources of the animal are used for diagnostic purposes, with serum being the most widely used. Bloom is rarely used; very little is known of its antigenicity and diagnostic performance, particularly when used with the enzyme linked immunosorbent assay (ELISA) method, which is the most popular test as it permits measurement of the antibody response. METHODS To (a) standardise an ELISA for the measurement of specific IgG against pigeon serum and pigeon bloom extract; (b) to establish reference values for specific IgG in 73 non-exposed controls, (c) to show the presence of specific IgG against pigeon serum and bloom in serum samples of 17 patients with bird fancier's lung and 11 asymptomatic fanciers, and (d) to study the similarity of the two antigen sources by cross reactivity experiments. RESULTS Reference values of specific IgG were defined with the 97.5 percentile (367.9 U/ml for pigeon serum and 953.7 U/ml for pigeon bloom extract). Of symptomatic patients 100% had values higher than the cut off for both antigens. In asymptomatic fanciers values were higher than the cut off for pigeon serum in 45% and bloom extract in 54%. Cross reactivity experiments showed that the two antigens differed in antigenic content although some components may be common to both. CONCLUSION The ELISA methods used proved to be useful tools for evaluating specific IgG antibody responses against both antigens. The diagnostic performance of both ELISA methods performed with these antigen sources was similar, showing very high sensitivity but moderate specificity. Although some antigenic similarity was found between pigeon serum and bloom extract, cross reactivity studies showed that various antigens seemed to be specific to the bloom extract. However, the antigens responsible for pigeon breeder's disease seem to be present in both antigenic sources.
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