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1.
J Adv Model Earth Syst ; 14(2): e2021MS002676, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35860620

ABSTRACT

Model Intercomparison Projects (MIPs) are fundamental to our understanding of how the land surface responds to changes in climate. However, MIPs are challenging to conduct, requiring the organization of multiple, decentralized modeling teams throughout the world running common protocols. We explored centralizing these models on a single supercomputing system. We ran nine offline terrestrial biosphere models through the Terrestrial Biosphere Model Farm: CABLE, CENTURY, HyLand, ISAM, JULES, LPJ-GUESS, ORCHIDEE, SiB-3, and SiB-CASA. All models were wrapped in a software framework driven with common forcing data, spin-up, and run protocols specified by the Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP) for years 1901-2100. We ran more than a dozen model experiments. We identify three major benefits and three major challenges. The benefits include: (a) processing multiple models through a MIP is relatively straightforward, (b) MIP protocols are run consistently across models, which may reduce some model output variability, and (c) unique multimodel experiments can provide novel output for analysis. The challenges are: (a) technological demand is large, particularly for data and output storage and transfer; (b) model versions lag those from the core model development teams; and (c) there is still a need for intellectual input from the core model development teams for insight into model results. A merger with the open-source, cloud-based Predictive Ecosystem Analyzer (PEcAn) ecoinformatics system may be a path forward to overcoming these challenges.

2.
Neurobiol Dis ; 161: 105546, 2021 12.
Article in English | MEDLINE | ID: mdl-34742878

ABSTRACT

Febrile seizures (FS) are common, affecting 2-5% of children between the ages of 3 months and 6 years. Complex FS occur in 10% of patients with FS and are strongly associated with mesial temporal lobe epilepsy. Current research suggests that predisposing factors, such as genetic and anatomic abnormalities, may be necessary for complex FS to translate to mesial temporal lobe epilepsy. Sex hormones are known to influence seizure susceptibility and epileptogenesis, but whether sex-specific effects of early life stress play a role in epileptogenesis is unclear. Here, we investigate sex differences in the activity of the hypothalamic-pituitary-adrenal (HPA) axis following chronic stress and the underlying contributions of gonadal hormones to the susceptibility of hyperthermia-induced seizures (HS) in rat pups. Chronic stress consisted of daily injections of 40 mg/kg of corticosterone (CORT) subcutaneously from postnatal day (P) 1 to P9 in male and female rat pups followed by HS at P10. Body mass, plasma CORT levels, temperature threshold to HS, seizure characteristics, and electroencephalographic in vivo recordings were compared between CORT- and vehicle (VEH)-injected littermates during and after HS at P10. In juvenile rats (P18-P22), in vitro CA1 pyramidal cell recordings were recorded in males to investigate excitatory and inhibitory neuronal circuits. Results show that daily CORT injections increased basal plasma CORT levels before HS and significantly reduced weight gain and body temperature threshold of HS in both males and females. CORT also significantly lowered the generalized convulsions (GC) latency while increasing recovery time and the number of electrographic seizures (>10s), which had longer duration. Furthermore, sex-specific differences were found in response to chronic CORT injections. Compared to females, male pups had increased basal plasma CORT levels after HS, longer recovery time and a higher number of electrographic seizures (>10s), which also had longer duration. Sex-specific differences were also found at baseline conditions with lower latency to generalized convulsions and longer duration of electrographic seizures in males but not in females. In juvenile male rats, the amplitude of evoked excitatory postsynaptic potentials, as well as the amplitude of inhibitory postsynaptic currents, were significantly greater in CORT rats when compared to VEH littermates. These findings not only validate CORT injections as a stress model, but also show a sex difference in baseline conditions as well as a response to chronic CORT and an impact on seizure susceptibility, supporting a potential link between sustained early-life stress and complex FS. Overall, these effects also indicate a putatively less severe phenotype in female than male pups. Ultimately, studies investigating the biological underpinnings of sex differences as a determining factor in mental and neurologic problems are necessary to develop better diagnostic, preventative, and therapeutic approaches for all patients regardless of their sex.


Subject(s)
Hyperthermia, Induced , Seizures, Febrile , Animals , Corticosterone , Female , Humans , Hyperthermia, Induced/adverse effects , Hypothalamo-Hypophyseal System , Male , Rats , Seizures/etiology , Seizures, Febrile/etiology , Sex Characteristics
3.
Clin Dermatol ; 39(2): 194-198, 2021.
Article in English | MEDLINE | ID: mdl-34272008

ABSTRACT

Necrotizing infundibular crystalline folliculitis is a rare condition characterized by folliculocentric waxy papules in the seborrheic areas of adult patients, with intrafollicular filamentous birefringent crystalline deposits as the histopathologic clue. Although the real pathogenesis of necrotizing infundibular crystalline folliculitis remains unclear, the intrafollicular material seems to be derived from an interaction between such superficial microorganisms as gram-positive bacteria (Propionibacterium acnes, Staphylococcus spp), Malassezia yeasts, and sebaceous lipids. Topical or systemic antiacne agents or antimycotics appear to be effective therapy.


Subject(s)
Folliculitis , Malassezia , Adult , Folliculitis/diagnosis , Folliculitis/drug therapy , Humans
4.
Nature ; 584(7819): 55-58, 2020 08.
Article in English | MEDLINE | ID: mdl-32760043

ABSTRACT

Lightning flashes have been observed by a number of missions that visited or flew by Jupiter over the past several decades. Imagery led to a flash rate estimate of about 4 × 10-3 flashes per square kilometre per year (refs. 1,2). The spatial extent of Voyager flashes was estimated to be about 30 kilometres (half-width at half-maximum intensity, HWHM), but the camera was unlikely to have detected the dim outer edges of the flashes, given its weak response to the brightest spectral line of Jovian lightning emission, the 656.3-nanometre Hα line of atomic hydrogen1,3-6. The spatial resolution of some cameras allowed investigators to confirm 22 flashes with HWHM greater than 42 kilometres, and to estimate one with an HWHM of 37 to 45 kilometres (refs. 1,7-9). These flashes, with optical energies comparable to terrestrial 'superbolts'-of (0.02-1.6) × 1010 joules-have been interpreted as tracers of moist convection originating near the 5-bar level of Jupiter's atmosphere (assuming photon scattering from points beneath the clouds)1-3,7,8,10-12. Previous observations of lightning have been limited by camera sensitivity, distance from Jupiter and long exposures (about 680 milliseconds to 85 seconds), meaning that some measurements were probably superimposed flashes reported as one1,2,7,9,10,13. Here we report optical observations of lightning flashes by the Juno spacecraft with energies of approximately 105-108 joules, flash durations as short as 5.4 milliseconds and inter-flash separations of tens of milliseconds, with typical terrestrial energies. The flash rate is about 6.1 × 10-2 flashes per square kilometre per year, more than an order of magnitude greater than hitherto seen. Several flashes are of such small spatial extent that they must originate above the 2-bar level, where there is no liquid water14,15. This implies that multiple mechanisms for generating lightning on Jupiter need to be considered for a full understanding of the planet's atmospheric convection and composition.

5.
Cancer Manag Res ; 10: 5537-5544, 2018.
Article in English | MEDLINE | ID: mdl-30519101

ABSTRACT

BACKGROUND: Prognosis of metastatic non-small cell lung cancer significantly improved with the availability of checkpoint inhibitors (anti-PD-1/PD-L1). Unfortunately, reliable biomarkers to predict treatment benefit are lacking. PATIENTS AND METHODS: We prospectively collected clinical and laboratory data of 56 non-small cell lung cancer patients treated with a checkpoint inhibitor. The aim was to identify baseline parameters correlating with worse outcome and to create a risk score that enabled to stratify patients into different risk groups. As inflammation is known to promote tumor growth, we focused on inflammation markers in the blood. Disease control (DC) was defined as complete response, partial response, and stable disease on CT scan according to RECIST 1.1. RESULTS: Half of the patients achieved DC. Four parameters differed significantly between the DC group and the no disease control group: Eastern Cooperative Oncology Group performance status (P=0.009), number of organs with metastases (P=0.001), lactate dehydrogenase (P=0.029), and ferritin (P=0.005). A risk score defined as the number of these parameters (0= no risk factor) exceeding a threshold (Eastern Cooperative Oncology Group performance status ≥2, number of organs with metastases ≥4, lactate dehydrogenase ≥262U/L, and ferritin ≥241 µg/L) was associated with overall survival and progression-free survival. Overall survival at 6 and 12 months is as follows: Scores 0-1: 95% and 95%; Score 2: 67% and ≤33%; Scores 3-4: 15% and 0%. Progression-free survival at 6 and 12 months is as follows: Scores 0-1: 81% and 50%; Score 2: 25% and ≤25%; Scores 3-4: 0% and 0%. CONCLUSION: We propose an easy-to-apply risk score categorizing patients into different risk groups before treatment start with a PD-1/PD-L1 antibody.

6.
Rev Med Suisse ; 13(556): 698-702, 2017 Mar 29.
Article in French | MEDLINE | ID: mdl-28722380

ABSTRACT

An algorithm is proposed to facilitate the management of onychomycosis and ensure a good therapeutical approach. Its aim is to simplify the diagnosis process by integrating a pertinent anamnesis and physical examination with the classic tool of mycology (direct examination, culture, eventually examination by PCR), in order to give the adequate targeted treatment.


Cet article propose un algorithme afin de faciliter la prise en charge thérapeutique et diagnostique de l'onychomycose. Il vise à simplifier la démarche diagnostique jusqu'à l'identification du champignon dont dépendra le traitement. Il permet de rappeler que toute onychodystrophie n'est pas une onychomycose.


Subject(s)
Algorithms , Foot Dermatoses/diagnosis , Onychomycosis/diagnosis , Foot Dermatoses/therapy , Humans , Onychomycosis/therapy , Physical Examination/methods , Polymerase Chain Reaction
7.
IEEE Trans Image Process ; 24(1): 359-73, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25494507

ABSTRACT

Foreground/background segmentation via change detection in video sequences is often used as a stepping stone in high-level analytics and applications. Despite the wide variety of methods that have been proposed for this problem, none has been able to fully address the complex nature of dynamic scenes in real surveillance tasks. In this paper, we present a universal pixel-level segmentation method that relies on spatiotemporal binary features as well as color information to detect changes. This allows camouflaged foreground objects to be detected more easily while most illumination variations are ignored. Besides, instead of using manually set, frame-wide constants to dictate model sensitivity and adaptation speed, we use pixel-level feedback loops to dynamically adjust our method's internal parameters without user intervention. These adjustments are based on the continuous monitoring of model fidelity and local segmentation noise levels. This new approach enables us to outperform all 32 previously tested state-of-the-art methods on the 2012 and 2014 versions of the ChangeDetection.net dataset in terms of overall F-Measure. The use of local binary image descriptors for pixel-level modeling also facilitates high-speed parallel implementations: our own version, which used no low-level or architecture-specific instruction, reached real-time processing speed on a midlevel desktop CPU. A complete C++ implementation based on OpenCV is available online.

8.
IEEE Trans Image Process ; 22(2): 668-78, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23047873

ABSTRACT

Computer vision is a noninvasive method for monitoring laboratory animals. In this article, we propose a robust tracking method that is capable of extracting a rodent from a frame under uncontrolled normal laboratory conditions. The method consists of two steps. First, a sliding window combines three features to coarsely track the animal. Then, it uses the edglets of the rodent to adjust the tracked region to the animal's boundary. The method achieves an average tracking error that is smaller than a representative state-of-the-art method.


Subject(s)
Behavior, Animal/classification , Image Processing, Computer-Assisted/methods , Monitoring, Ambulatory/methods , Video Recording/methods , Algorithms , Animals , Housing, Animal , Rats
9.
Clin J Am Soc Nephrol ; 7(3): 472-8, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22241817

ABSTRACT

BACKGROUND AND OBJECTIVES: Gitelman syndrome (GS) is a salt-wasting tubulopathy that results from the inactivation of the human thiazide-sensitive sodium chloride cotransporter located in the distal convoluted tubule. Tubular adaptation to renal sodium loss has been described and localized in the distal tubule in experimental models of GS but not in humans with GS. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: The tubular adaptation to renal sodium loss is described. Osmole-free water clearance and endogenous lithium clearance with furosemide infusion are used to compare 7 patients with genetically confirmed GS and 13 control participants. RESULTS: Neither endogenous lithium clearance nor osmole-free water clearance disclosed enhanced proximal fluid reabsorption in patients with GS. These patients displayed significantly lower osmole-free water clearance factored by inulin clearance (7.1 ± 1.9 versus 10.1 ± 2.2; P<0.01) and significantly lower fractional sodium reabsorption in the diluting nephron (73.2% ± 7.1% versus 86.1% ± 4.7%; P<0.005), consistent with the inactivation of the thiazide-sensitive sodium chloride cotransporter. The furosemide-induced reduction rate of fractional sodium reabsorption in the diluting segment was higher in patients with GS (75.6% ± 6.1% versus 69.9% ± 3.2%; P<0.039), suggesting that sodium reabsorption would be enhanced in the cortical part of the thick ascending limb of the loop of Henle in patients with GS. CONCLUSIONS: These findings suggest that tubular adaptation to renal sodium loss in GS would be devoted to the cortical part of the thick ascending limb of the loop of Henle in humans.


Subject(s)
Gitelman Syndrome/metabolism , Kidney Tubules/metabolism , Receptors, Drug/metabolism , Sodium/metabolism , Symporters/metabolism , Adaptation, Physiological , Adult , Case-Control Studies , Diuretics/administration & dosage , Female , France , Furosemide/administration & dosage , Genetic Predisposition to Disease , Gitelman Syndrome/blood , Gitelman Syndrome/genetics , Gitelman Syndrome/urine , Humans , Infusions, Intravenous , Inulin , Kidney Tubules/drug effects , Lithium/metabolism , Male , Middle Aged , Osmolar Concentration , Phenotype , Receptors, Drug/genetics , Sodium/blood , Sodium/urine , Solute Carrier Family 12, Member 3 , Symporters/genetics , Time Factors , Water-Electrolyte Balance
10.
Conscious Cogn ; 20(4): 1738-43, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21296005

ABSTRACT

In developmental lexical-gustatory synesthesia, specific words (inducers) can trigger taste perceptions (concurrents) and these synesthetic associations are generally stable. We describe a case of multilingual lexical-gustatory synesthesia for whom some synesthesias were bidirectional as some tastes also triggered auditory word associations. Evoked concurrents could be gustatory but also tactile sensations. In addition to words and pseudowords, many voices were effective inducers, suggesting increased connections between cortical taste areas and both voice-selective and language-selective areas. Lasting changes in some evoked tastes occurred during childhood suggesting that some plasticity can be present after the initial learning of associations. Inducers were often linked to taste concurrents phonologically or semantically, but also through identifiable childhood episodes (persons or events). Several inducers were phonologically linked to episodic inducers suggesting a process of secondary acquisition for many inducers. Implications of these observations are discussed.


Subject(s)
Auditory Perception , Perceptual Disorders/psychology , Psycholinguistics , Taste Perception , Female , Food , Humans , Multilingualism , Vocabulary , Young Adult
11.
J Med Syst ; 35(3): 377-89, 2011 Jun.
Article in English | MEDLINE | ID: mdl-20703552

ABSTRACT

This paper presents a computer vision system for monitoring medication intake in the context of home care services. We use a method based on color and shape to detect the body parts and the medication bottles. Color is used for skin detection, and the shape is used to distinguish the face from the hands and to differentiate bottles of medicine. To track these objects, we use a method based on color histograms, Hu moments, and edges. For the recognition of medication intake, we use a Petri network and event recognition. Our method has an accuracy of more than 75% and allows the detection of the medication intake in various scenarios where the user is cooperative.


Subject(s)
Medication Adherence , Pattern Recognition, Automated/methods , Signal Processing, Computer-Assisted/instrumentation , Artificial Intelligence , Face , Hand , Home Care Services , Humans , Reproducibility of Results , Video Recording
12.
Sensors (Basel) ; 10(2): 1041-61, 2010.
Article in English | MEDLINE | ID: mdl-22205857

ABSTRACT

This paper presents a region-based method for background subtraction. It relies on color histograms, texture information, and successive division of candidate rectangular image regions to model the background and detect motion. Our proposed algorithm uses this principle and combines it with Gaussian mixture background modeling to produce a new method which outperforms the classic Gaussian mixture background subtraction method. Our method has the advantages of filtering noise during image differentiation and providing a selectable level of detail for the contour of the moving shapes. The algorithm is tested on various video sequences and is shown to outperform state-of-the-art background subtraction methods.


Subject(s)
Algorithms , Models, Theoretical , Pattern Recognition, Automated
13.
Neurobiol Dis ; 35(2): 209-18, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19442734

ABSTRACT

In this study, we demonstrate that gamma oscillations (30-50 Hz) recorded in the local field potentials (LFP) of the hippocampus are a marker of temporal lobe seizure propagation and that the level of LFP synchrony in the amygdalo-hippocampal network, during these oscillations, is related to the severity of seizures. Sprague-Dawley rats were given a single systemic dose of kainic acid (KA; 6 mg/kg, i.p.) and local field potential activity (1-475 Hz) of the dorsal hippocampus, the amygdala and the neocortex was recorded. Of 135 ictal discharges, 55 (40.7%) involved both limbic structures. We demonstrated that 78.2% of seizures involving both the hippocampus and amygdala showed hippocampal gamma oscillations. Seizure duration was also significantly correlated with the frequency of hippocampal gamma oscillations (r2=0.31, p<0.01) and LFP synchrony in the amygdalo-hippocampal network (r2=0.21, p<0.05). These results suggest that gamma oscillations in the amygdalo-hippocampal network could facilitate long-range synchrony and participate in the propagation of seizures.


Subject(s)
Amygdala/physiopathology , Hippocampus/physiopathology , Periodicity , Seizures/physiopathology , Analysis of Variance , Animals , Cerebral Cortex/physiopathology , Kainic Acid , Microelectrodes , Neural Pathways/physiopathology , Rats , Rats, Sprague-Dawley , Seizures/chemically induced , Severity of Illness Index , Time Factors
14.
Comput Med Imaging Graph ; 30(8): 437-46, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17029724

ABSTRACT

This paper presents a graph-based segmentation method using multiple criteria in successive stages to segment thoracoscopic images acquired during a diskectomy procedure commonly used for thoracoscopic anterior release and fusion for scoliosis treatment. Starting with image pre-processing, including Gaussian smoothing, brightness and contrast enhancement, and histogram thresholding, a standard graph-based method is applied to produce a coarse segmentation of thoracoscopic images. Next, regions are further merged in a multistage graph-based process based on features like grey-level similarity, region size and common edge length. Experimental results show that our approach achieves good spatial coherence, accurate edge location and appropriate segmentation of the regions of interest from a sequence of thoracoscopic images.


Subject(s)
Diskectomy/methods , Image Processing, Computer-Assisted , Imaging, Three-Dimensional/methods , Thoracoscopy/methods , Algorithms , Humans , Thoracic Surgery, Video-Assisted/methods
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