We analyze the onset and initial expansion of the 2018 Martian Global Dust Storm (GDS 2018) using ground‐based images in the visual range. This is the first case of a confirmed GDS initiating in the ...Northern Hemisphere. A dusty area extending about 1.4×105 km2 and centered at latitude +31.7°±1.8° and west longitude 18°±5°W in Acidalia Planitia was captured on 30 and 31 May 2018 (Ls = 184.9°). From 1 to 8 June, daily image series showed the storm expanding southward along the Acidalia corridor with velocities of 5 m/s and simultaneously progressing eastward and westward with horizontal velocities ranging from 5 to 40 m/s. By 8 June the dust reached latitude ‐55° and later penetrated in the South polar region, whereas in the North the dust progression stopped at latitude approximately +46°. We compare the onset and expansion stage of this GDS with the previous confirmed storms.
Key Points
May‐June 2018 ground‐based images show the onset and early evolution of a Martian Global Dust Storm (GDS)
The outbreak took place at location (North hemisphere) and time (solar longitude 184.9°) unusual for most GDSs
The expansion involved horizontal velocities in all directions in the range 5‐40 m/s
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
A speech signal captured by a distant microphone is generally smeared by reverberation, which severely degrades automatic speech recognition (ASR) performance. One way to solve this problem is to ...dereverberate the observed signal prior to ASR. In this paper, a room impulse response is assumed to consist of three parts: a direct-path response, early reflections and late reverberations. Since late reverberations are known to be a major cause of ASR performance degradation, this paper focuses on dealing with the effect of late reverberations. The proposed method first estimates the late reverberations using long-term multi-step linear prediction, and then reduces the late reverberation effect by employing spectral subtraction. The algorithm provided good dereverberation with training data corresponding to the duration of one speech utterance, in our case, less than 6 s. This paper describes the proposed framework for both single-channel and multichannel scenarios. Experimental results showed substantial improvements in ASR performance with real recordings under severe reverberant conditions.
The conformation of polymer chains grafted on a substrate influences protein adsorption. In a previous study, adsorption/desorption of albumin was demonstrated on mixed poly(ethylene oxide) ...(PEO)/poly(acrylic acid) (PAA) brushes, triggered by solutions of adequate pH and ionic strength (I). In the present work, homolayers of PEO or PAA are submitted to saline solutions with pH from 3 to 9 and I from 10–5 to 10–1 M, and their conformation is evaluated in real time using quartz crystal microbalance with dissipation monitoring (QCM-D). Shrinkage/swelling of PAA chains and hydration and salt condensation in the brush are evidenced. The adsorption of human serum albumin (HSA) onto such brushes is also monitored in these different saline solutions, leading to a deep understanding of the influence of polymer chain conformation, modulated by pH and I, on protein adsorption. A detailed model of the conformation of PEO/PAA mixed brushes depending on pH and I is then proposed, providing a rationale for the identification of conditions for the successive adsorption and desorption of proteins on such mixed brushes. The adsorption/desorption of albumin on PEO/PAA is demonstrated using QCM-D
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IJS, KILJ, NUK, PNG, UL, UM
Summary
Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare but feared long‐term complication of acute pulmonary embolism (PE), although CTEPH may occur in patients with no history of ...symptomatic venous thromboembolism. It represents the most severe presentation of the so‐called ‘post‐PE syndrome’, a phenomenon of permanent functional limitations after PE caused by deconditioning after PE or ventilatory or circulatory impairment as a result of unresolved pulmonary artery thrombi. Because the post‐PE syndrome may occur in up to 50% of PE survivors, and CTEPH tends to have an insidious and non‐specific clinical presentation, CTEPH is often not diagnosed or diagnosed after a very long delay. Once the diagnosis is confirmed, the treatment of choice is pulmonary endarterectomy which effectively lowers the pulmonary vascular resistance and normalizes resting pulmonary artery pressures, leading to recovery of the right ventricle. When pulmonary endarterectomy is not technically feasible, balloon pulmonary angioplasty may be a potential acceptable alternative. Also, medical treatment may help to improve patient's symptoms and hemodynamics. Current studies are focusing on strategies for earlier CTEPH diagnosis after acute PE, as well as the most optimal treatment of inoperable patients. This review will focus on the epidemiology, risk factors, diagnosis and treatment of CTEPH from the perspective of the PE patient.
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FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
To quantify right ventricular (RV) function in patients with chronic thromboembolic pulmonary hypertension (CTEPH) before and after pulmonary endarterectomy (PEA).
Out of 33 patients, 16 were ...evaluated clinically and with echocardiography (conventional and myocardial deformation parameters) before PEA (preop) and at 1 week, 1 month, 3 months and 6 months after PEA. RV fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE) as well as mid-apical and basal peak ejection strain (S) and strain rate (SR) of the RV free wall were measured. Left ventricular (LV) apical lateral wall motion was regarded as indicating changes in overall heart rocking motion (RM). Heart catheterisation was performed before, within 1 week and at 6 months after PEA.
Clinical and haemodynamic parameters improved significantly after PEA. This correlated with the improvement in RVFAC, S and SR. TAPSE, on the other hand, showed a biphasic response (14.5 (4) mm preop, 8.5 (2.7) mm at 1 week and 11 (1.5) mm at 6 months). Changes in LV apical motion explain this finding. At baseline, TAPSE was enhanced by rocking motion of the heart as a result of the failing RV. Unloading the RV by PEA normalised the rocking motion and TAPSE decreased.
RV function of CTEPH patients improves steadily after PEA. Unlike S, SR and RVFAC, this is not reflected by TAPSE because of postoperative changes in overall heart motion. Motion independent deformation parameters (S, SR) appear superior in the accurate description of regional RV function.
Context. Video observations of Jupiter obtained by amateur astronomers over the past 8 years have shown five flashes of light with durations of 1–2 s, each observed by at least two observers that ...were geographically separated. The first three of these events occurred on 3 June 2010, 20 August 2010, and 10 September 2012. Previous analyses of their light curves showed that they were caused by the impact of objects of 5–20 m in diameter, depending on their density, with a released energy comparable to superbolides on Earth of the class of the Chelyabinsk airburst. The most recent two flashes on Jupiter were detected on 17 March 2016 and 26 May 2017 and are analyzed here. Aims. We characterize the energy involved together with the masses and sizes of the objects that produced these flashes. The rate of similar impacts on Jupiter provides improved constraints on the total flux of impacts on the planet, which can be compared to the amount of exogenic species detected in the upper atmosphere of Jupiter. Methods. We extracted light curves of the flashes and calculated the masses and sizes of the impacting objects after calibrating each video observation. We also present results from a systematic search of impacts on >72 000 video amateur observations with a customized software that is based on differential photometry of the images. An examination of the number of amateur observations of Jupiter as a function of time over the past years allows us to interpret the statistics of these impact detections. Results. The cumulative flux of small objects (5–20 m or larger) that impact Jupiter is predicted to be low (10–65 impacts per year), and only a fraction of them are potentially observable from Earth (4–25 observable impacts per year in a perfect survey). These numbers imply that many observers are required to efficiently discover Jupiter impacts. Conclusions. We predict that more impacts will be found in the next years, with Jupiter opposition displaced toward summer in the northern hemisphere where most amateur astronomers observe. Objects of this size contribute negligibly to the abundance of exogenous species and dust in the stratosphere of Jupiter when compared with the continuous flux from interplanetary dust particles punctuated by giant impacts. Flashes of a high enough brightness (comparable at their peak to a +3.3 magnitude star) could produce an observable debris field on the planet. We estimate that a continuous search for these impacts might find these events once every 0.4–2.6 yr.
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Adsorption of proteins at interfaces is an ubiquitous phenomenon of prime importance. Layers of poly(ethylene oxide) (PEO) are widely used to repel proteins. Conversely, proteins were shown to adsorb ...deeply into brushes of poly(acrylic acid) (PAA), and their subsequent partial release could be triggered by a change of pH and/or ionic strength (I). Mixed brushes of these polymers are thus promising candidates to tune protein adsorption onto new smart surfaces. In this work, the synthesis of such mixed brushes was performed based on a “grafting to” approach, the two polymers being either grafted sequentially or simultaneously. Detailed characterization of the obtained brushes using static water contact angle measurements, X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, and polarization–modulation reflection–absorption infrared spectroscopy is presented. While sequential grafting of the two polymers for different reactions times did not give rise to a broad range of composition of mixed brushes, simultaneous grafting of the polymers from solutions with different compositions allows for the synthesis of a range of mixed brushes (mass fraction of PEO in the mixed brushes from 0.35 to 0.65). A key example is then chosen to illustrate the switchable behavior of a selected mixed PEO/PAA brush toward albumin adsorption. The adsorption behavior was monitored with a quartz crystal microbalance. The mixed brush could adsorb high amounts of albumin, but 86% of the adsorbed protein could then be desorbed upon pH and I change. The obtained properties are thus a combination of the ones of PEO and PAA, and a highly switchable behavior is observed toward protein adsorption.
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IJS, KILJ, NUK, PNG, UL, UM
Abstract
STUDY QUESTION
Could whole-exome sequencing (WES) be useful in clinical practice for men with maturation arrest (MA) after a first testicular sperm extraction (TESE)?
SUMMARY ANSWER
WES in ...combination with TESE yields substantial additional information and may potentially be added as a test to predict a negative outcome of a recurrent TESE in patients with MA.
WHAT IS KNOWN ALREADY
At present, the only definitive contraindications for TESE in men with non-obstructive azoospermia (NOA) are a 46,XX karyotype and microdeletions in the azoospermia factor a (AZFa) and/or AZFb regions. After a first negative TESE with MA, no test currently exists to predict a negative outcome of a recurrent TESE.
STUDY DESIGN, SIZE, DURATION
In a cohort study, we retrospectively included 26 patients with idiopathic NOA caused by complete MA diagnosed after a first TESE.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Twenty-six men with MA at the spermatocyte stage in all seminiferous tubules, according to a histopathological analysis performed independently by two expert histologists, and a normal karyotype (i.e. no AZF gene microdeletions on the Y chromosome) were included. Single-nucleotide polymorphism comparative genomic hybridization array and WES were carried out. The results were validated with Sanger sequencing. For all the variants thought to influence spermatogenesis, we used immunohistochemical techniques to analyse the level of the altered protein.
MAIN RESULTS AND THE ROLE OF CHANCE
Deleterious homozygous variants were identified in all seven consanguineous patients and in three of the 19 non-consanguineous patients. Compound heterozygous variants were identified in another 5 of the 19 non-consanguineous patients. No recurrent variants were identified. We found new variants in genes known to be involved in azoospermia or MA including testis expressed 11 (TEX11), meiotic double-stranded break formation protein 1 (MEI1), proteasome 26s subunit, ATPase 3 interacting protein (PSMC3IP), synaptonemal complex central element protein 1 (SYCE1) and Fanconi anaemia complementation group M (FANCM) and variants in genes not previously linked to human MA (including CCCTC-binding factor like (CTCFL), Mov10 like RISC complex RNA helicase 1 (MOV10L1), chromosome 11 open reading frame 80 (C11ORF80) and exonuclease 1 (EXO1).
LARGE SCALE DATA
Data available on request
LIMITATIONS, REASONS FOR CAUTION
More data are required before WES screening can be used to avoid recurrent TESE, although screening should be recommended for men with a consanguineous family background. WES is still a complex technology and can generate incidental findings.
WIDER IMPLICATIONS OF THE FINDINGS
Our results confirmed the genetic aetiology of MA in most patients: the proportion of individuals with at least one pathologic variant was 50% in the overall study population and 100% in the consanguineous patients. With the exception of MEI1 (compound heterozygous variants of which were identified in two cases), each variant corresponded to a specific gene—confirming the high degree of genetic heterogeneity in men with MA. Our results suggest that WES screening could help to avoid recurrent, futile TESE in men with MA in general and in consanguineous individuals in particular, but these results need to be confirmed in future studies before clinical implementation.
STUDY FUNDING/COMPETING INTEREST(S)
The study was funded by the Fondation Maladies Rares (Paris, France), Merck (Kenilworth, NJ, USA), IRSF (Montigny le Bretonneux, France) and Agence de la Biomédecine (Saint Denis, France). There are no competing interests.
TRIAL REGISTRATION NUMBER
N/A.
Pulmonary arterial hypertension (PAH) is a rare and potentially fatal disease whose management is usually restricted to a few specialised centres. As patients do not necessarily live in the ...neighbourhood of these centres, daily care and emergencies have to be delegated to first and second lines. Treatment guidelines do not usually provide recommendations for acute emergency situations as evidence is scarce. This short review provides a description of our therapeutic protocols based on available data. A model of transmural organisation of care for PAH patients, currently applied in Belgium, is described. Thereafter, based on an analysis of the reasons of death in the PAH population, a review of the main emergencies is provided. Cardiac arrest and resuscitation, decompensated right heart failure, respiratory failure, arrhythmia, pericardial effusion, haemoptysis, surgery and drug-related adverse events will be discussed successively. Case reports showing the precariousness of PAH patients will enforce our thesis of the need for optimal patient management organisation.
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Adsorption of proteins on surfaces placed in biological fluids is a ubiquitous and mostly irreversible phenomenon, desirable or not, but often uncontrolled. Adsorption of most ...proteins on poly(ethylene oxide) (PEO) brushes is very limited, while the amount of proteins adsorbed on poly(acrylic acid) (PAA) brushes varies with the pH and ionic strength (I) of the protein solution. Mixed brushes of PEO and PAA are designed here to reversibly adsorb and desorb albumin, lysozyme, collagen and immunoglobulin G, four very different proteins in terms of size, solubility and isoelectric point. Protein adsorption and desorption are monitored using X-ray photoelectron spectroscopy, as well as with quartz crystal microbalance for in situ and real-time measurements. Large amounts of protein are adsorbed and then nearly completely desorbed on mixed PEO/PAA brushes by a simple pH and I trigger. The mixed brushes thus nicely combine the properties of pure PAA and pure PEO brushes. These adsorption/desorption cycles are shown to be repeated with high efficiency. The high-performance smart substrates created here could find applications in domains as diverse as biosensors, drug delivery and nanotransport.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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