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https://www.readbyqxmd.com/read/29782503/impact-and-recovery-process-of-mini-flash-crashes-an-empirical-study
#1
Tobias Braun, Jonas A Fiegen, Daniel C Wagner, Sebastian M Krause, Thomas Guhr
In an Ultrafast Extreme Event (or Mini Flash Crash), the price of a traded stock increases or decreases strongly within milliseconds. We present a detailed study of Ultrafast Extreme Events in stock market data. In contrast to popular belief, our analysis suggests that most of the Ultrafast Extreme Events are not necessarily due to feedbacks in High Frequency Trading: In at least 60 percent of the observed Ultrafast Extreme Events, the largest fraction of the price change is due to a single market order. In times of financial crisis, large market orders are more likely which leads to a significant increase of Ultrafast Extreme Events occurrences...
2018: PloS One
https://www.readbyqxmd.com/read/29782390/suspecting-hyperferritinemic-sepsis-in-iron-deficient-population-do-we-need-a-lower-plasma-ferritin-threshold
#2
Swarup Ghosh, Arun K Baranwal, Prateek Bhatia, Karthi Nallasamy
OBJECTIVES: Hyperferritinemia is being suggested to identify patients with sepsis-induced macrophage activation syndrome for early intervention. However, data among iron-deficient children are scarce. This study was planned to explore the biological behavior of plasma ferritin in children from communities with a high frequency of iron deficiency with septic shock and its association with the outcome. DESIGN: Prospective observational study. SETTING: Tertiary care teaching hospital in a low-middle income economy of South Asia...
May 18, 2018: Pediatric Critical Care Medicine
https://www.readbyqxmd.com/read/29782294/the-value-of-high-frequency-20-mhz-ultrasonography-for-preoperative-measurement-of-cutaneous-melanoma-thickness
#3
Andrea Kozárová, Marek Kozár, Ingrid Tonhajzerová, Táňa Pappová, Eva Minariková
High-frequency ultrasonography has become an important diagnostic tool in dermatovenerology. It is used for assessment of the cutaneous layers in diverse benign and malignant skin lesions and diseases. Herein we present the practical value of preoperative measurement of cutaneous melanoma thickness, the explanation of the possible reasons for different sonographic and histologic Breslow thickness, and the practical importance of high-frequency 20 MHz ultrasonography in preoperative measurements of cutaneous melanoma thickness...
April 2018: Acta Dermatovenerologica Croatica: ADC
https://www.readbyqxmd.com/read/29782258/-contractile-function-of-isolated-hearts-with-preserved-and-reduced-ejection-fraction-in-vivo
#4
V L Lakomkin, A A Abramov, V V Gramovich, O N Vyborov, I M Studneva, O I Pisarenko, V I Kapelko
The aim of the study was comparison of contractile function of isolated hearts of rats with doxorubicin-induced myocardial injury which were tentatively divided according to the level of ejection fraction determined by echocardiography in vivo. After 4 weeks of doxorubicin administration (2 mg/kg subcutaneously once a week) about half of animals had normal (86±1 %) and the other half reduced (61±4 %) ejection fraction. The first group was defined as diastolic heart failure (DHF) and the other as systolic (SHF)...
April 2018: Kardiologiia
https://www.readbyqxmd.com/read/29781990/fetal-mouse-cardiovascular-imaging-using-a-high-frequency-ultrasound-30-45mhz-system
#5
Marlin Touma
Congenital heart defects (CHDs) are the most common cause of childhood morbidity and early mortality. Prenatal detection of the underlying molecular mechanisms of CHDs is crucial for inventing new preventive and therapeutic strategies. Mutant mouse models are powerful tools to discover new mechanisms and environmental stress modifiers that drive cardiac development and their potential alteration in CHDs. However, efforts to establish the causality of these putative contributors have been limited to histological and molecular studies in non-survival animal experiments, in which monitoring the key physiological and hemodynamic parameters is often absent...
May 5, 2018: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/29781566/the-5-ht7-receptor-is-up-regulated-in-onuf-s-nucleus-in-rats-with-chronic-spinal-cord-injury
#6
Jianshu Ni, Nailong Cao, Xiaohu Wang, Changsheng Zhan, Jiemin Si, Baojun Gu, Karl-Erik Andersson
OBJECTIVES: To examine the effect of intrathecal 5-HT7 agonist administration on voiding function in urethane-anesthetized rat, and the change of 5-HT7 receptor expression in lumbosacral cord Onuf's nucleus after SCI. MATERIALS AND METHODS: Thirty-two female Sprague-Dawley (SD) rats were divided into spinally intact (SI) group and SCI group (n=16 each). Eight weeks after transection, half of the rats underwent continuous cystometry under urethane anesthetization, and the 5-HT7 selective agonist LP44 was given intrathecally...
May 21, 2018: BJU International
https://www.readbyqxmd.com/read/29781414/prevalence-of-human-papillomavirus-types-associated-with-cervical-lesions-in-sergipe-state-northeastern-brazil-high-frequency-of-a-possibly-carcinogenic-type
#7
I G S S Serra, E D Araujo, G S Barros, F L S G Santos, R Q Gurgel, M V A Batista
Persistent infection with high-risk human papillomavirus (HPV) is the main cause of cervical cancer and the prevalence of HPV types varies depending on the geographic region. Therefore, this study assessed the prevalence of HPV types in women with cervical lesions from Sergipe state, Northeastern Brazil. A cross-sectional study was conducted in women with cervical lesions from March to December 2014. These lesions were investigated by PCR and HPV types were identified by DNA sequencing. 432 patients were included, of which 337 patients tested positive for HPV...
May 21, 2018: Epidemiology and Infection
https://www.readbyqxmd.com/read/29781183/a-comparison-of-1-and-3-2-mhz-low-intensity-pulsed-ultrasound-on-osteogenesis-on-porous-titanium-alloy-scaffolds-an-in-vitro-and-in-vivo-study
#8
Lifang Feng, Xiaohan Liu, Hongjuan Cao, Limei Qin, Wentao Hou, Lin Wu
OBJECTIVES: Low-intensity pulsed ultrasound (LIPUS) combined with porous scaffolds can be used as a new therapy to treat bone defect repair. The aim of this study was to evaluate the effects of 1 and 3.2 MHz LIPUS on osteogenesis on porous Ti64 alloy scaffolds for both in vitro and in vivo studies. METHODS: Scaffolds were randomly divided into the high-frequency ultrasound group, low-frequency ultrasound group, and control group. Mouse pre-osteoblast cells were cultured with porous Ti-6Al-4V scaffolds in vitro to evaluate cell proliferation and differentiation...
May 21, 2018: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
https://www.readbyqxmd.com/read/29781163/effects-of-night-duty-events-on-blood-pressure-and-autonomic-modulation-in-physicians
#9
Hsiu-Hao Lee, Bing-Yu Chen, Shih-Chun Pan, Shih-Hsiang Lo, Pau-Chung Chen, Yue Leon Guo
BACKGROUND: The dynamic effects of duty events on the blood pressure (BP) and heart rate variability (HRV) of physicians on duty are unknown. METHODS: A study was conducted among 12 physicians on night duty. BP and HRV with and without the effect of a duty event were compared. The risk of higher BP and impaired HRV after a phone call were calculated. RESULTS: Physicians had higher mean BP (122.4 ± 11.1; 76.9 ± 7.1 mmHg) within 30 min after a phone calls than without a phone call (113...
May 20, 2018: American Journal of Industrial Medicine
https://www.readbyqxmd.com/read/29780824/clinical-histological-and-immunohistochemical-findings-in-inclusion-body-myositis
#10
Leonardo Valente de Camargo, Mary Souza de Carvalho, Samuel Katsuyuki Shinjo, Acary Souza Bulle de Oliveira, Edmar Zanoteli
Sporadic inclusion body myositis (sIBM) is considered the most common acquired myopathy aged over 50 years. The disease is characterized by a particular process of muscle degeneration characterized by abnormal deposit of protein aggregates in association with inflammation. The aim of this study was to present clinical and muscle histopathological findings, including immunostaining for LC3B, p62, α -synuclein, and TDP-43, in 18 patients with sIBM. The disease predominated in males (61%) and European descendants, with onset of clinical manifestations around 59 years old...
2018: BioMed Research International
https://www.readbyqxmd.com/read/29780593/interacting-with-wildlife-tourism-increases-activity-of-white-sharks
#11
Charlie Huveneers, Yuuki Y Watanabe, Nicholas L Payne, Jayson M Semmens
Anthropogenic activities are dramatically changing marine ecosystems. Wildlife tourism is one of the fastest growing sectors of the tourism industry and has the potential to modify the natural environment and behaviour of the species it targets. Here, we used a novel method to assess the effects of wildlife tourism on the activity of white sharks ( Carcharodon carcharias ). High frequency three-axis acceleration loggers were deployed on ten white sharks for a total of ~9 days. A combination of multivariate and univariate analysis revealed that the increased number of strong accelerations and vertical movements when sharks are interacting with cage-diving operators result in an overall dynamic body acceleration (ODBA) ~61% higher compared with other times when sharks are present in the area where cage-diving occurs...
2018: Conservation Physiology
https://www.readbyqxmd.com/read/29780311/characteristics-of-rest-and-postural-tremors-in-parkinson-s-disease-an-analysis-of-motor-unit-firing-synchrony-and-patterns
#12
Orsalia M Agapaki, Constantinos N Christakos, Dimitrios Anastasopoulos
The neural mechanisms responsible for resting and postural tremor in Parkinson's disease (PD) have been the object of considerable study, much of it focusing on supraspinal sites. Here, we adopted an alternative approach that emphasizes motor unit (MU) firing synchrony and patterns of discharge. To explore if these could account for known features of PD tremor, we recorded the instantaneous acceleration of the upper limb of 23 PD patients at rest or while they tried to hold a stable posture together with surface EMG and single MU discharges of upper limb muscles...
2018: Frontiers in Human Neuroscience
https://www.readbyqxmd.com/read/29780301/when-the-ostrich-algorithm-fails-blanking-method-affects-spike-train-statistics
#13
Kevin Joseph, Soheil Mottaghi, Olaf Christ, Thomas J Feuerstein, Ulrich G Hofmann
Modern electroceuticals are bound to employ the usage of electrical high frequency (130-180 Hz) stimulation carried out under closed loop control, most prominent in the case of movement disorders. However, particular challenges are faced when electrical recordings of neuronal tissue are carried out during high frequency electrical stimulation, both in-vivo and in-vitro . This stimulation produces undesired artifacts and can render the recorded signal only partially useful. The extent of these artifacts is often reduced by temporarily grounding the recording input during stimulation pulses...
2018: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/29780078/work-related-injuries-and-fatalities-in-the-geotechnical-site-works
#14
Özge Akboğa Kale, Tuğba Eskişar
Geotechnical site works are comprehensive, and they constitute the first step of the construction process. This study performs data mining of geotechnical works and analyzes the database for the root causes of accidents. The Occupational Safety and Health Administration (OSHA) was chosen for the 1984-2013 time frame with 247 cases. Descriptive statistical analyses were performed to discuss variables such as the end use of the work, project type and cost, soil type and condition, type and degree of injury, cause and type of accident, unsafe acts, and occupation and union status of the victim...
May 19, 2018: Industrial Health
https://www.readbyqxmd.com/read/29779963/action-potential-initiation-propagation-and-cortical-invasion-in-the-hyperdirect-pathway-during-subthalamic-deep-brain-stimulation
#15
Ross W Anderson, AmirAli Farokhniaee, Kabilar Gunalan, Bryan Howell, Cameron C McIntyre
BACKGROUND: High frequency (∼130 Hz) deep brain stimulation (DBS) of the subthalamic region is an established clinical therapy for the treatment of late stage Parkinson's disease (PD). Direct modulation of the hyperdirect pathway, defined as cortical layer V pyramidal neurons that send an axon collateral to the subthalamic nucleus (STN), has emerged as a possible component of the therapeutic mechanisms. However, numerous questions remain to be addressed on the basic biophysics of hyperdirect pathway stimulation...
May 12, 2018: Brain Stimulation
https://www.readbyqxmd.com/read/29778290/spatial-hearing-ability-of-the-pigmented-guinea-pig-cavia-porcellus-minimum-audible-angle-and-spatial-release-from-masking-in-azimuth
#16
Nathaniel T Greene, Kelsey L Anbuhl, Alexander T Ferber, Marisa DeGuzman, Paul D Allen, Daniel J Tollin
Despite the common use of guinea pigs in investigations of the neural mechanisms of binaural and spatial hearing, their behavioral capabilities in spatial hearing tasks have surprisingly not been thoroughly investigated. To begin to fill this void, we tested the spatial hearing of adult male guinea pigs in several experiments using a paradigm based on the prepulse inhibition (PPI) of the acoustic startle response. In the first experiment, we presented continuous broadband noise from one speaker location and switched to a second speaker location (the "prepulse") along the azimuth prior to presenting a brief, ∼110 dB SPL startle-eliciting stimulus...
April 27, 2018: Hearing Research
https://www.readbyqxmd.com/read/29778241/dual-autonomic-inhibitory-action-of-central-apelin-on-gastric-motor-functions-in-rats
#17
Mehmet Bülbül, Osman Sinen
Centrally administered apelin has been shown to inhibit gastric emptying (GE) in rodents, however, the relevant mechanism has been investigated incompletely. Using male Wistar rats, we investigated the efferent pathways involved in gastroinhibitory action of central apelin. Stereotaxic intracerebroventricular (icv) cannulation, subdiaphragmatic vagotomy (VGX) and/or celiac ganglionectomy (CGX) were performed 7 days prior to the experiments. Apelin-13 was administered (30 nmol, icv) 90 min prior to GE measurement...
July 2018: Autonomic Neuroscience: Basic & Clinical
https://www.readbyqxmd.com/read/29778240/the-autonomic-neural-mechanism-of-right-ventricular-outflow-tract-tachycardia
#18
Hung-Yu Chang, Li-Wei Lo, Yu-Ruey Chen, Yu-Hui Chou, Wei-Lun Lin, Yenn-Jiang Lin, Wei-Hsian Yin, An-Ning Feng, Shih-Ann Chen
BACKGROUND: Ventricular tachycardia (VT) and ventricular premature complexes (VPCs) originating from the right ventricular outflow tract (RVOT) are generally considered as benign arrhythmias, with ECG morphology showing LBBB pattern and inferior axis. Pathogenic mechanisms in the genesis of RVOT VT/VPC remain largely unknown. We aimed to investigate the neural mechanism in RVOT ventricular arrhythmias in canine model. METHODS: Twelve mongrel dogs (13.7 ± 1...
July 2018: Autonomic Neuroscience: Basic & Clinical
https://www.readbyqxmd.com/read/29778232/nuclear-bap1-loss-is-common-in-intrahepatic-cholangiocarcinoma-and-a-subtype-of-hepatocellular-carcinoma-but-rare-in-pancreatic-ductal-adenocarcinoma
#19
Asmaa Mosbeh, Khalil Halfawy, Wael S Abdel-Mageed, Dina Sweed, Mohamed H Abdel Rahman
Deletion in the 3p21 region, the chromosomal location of BAP1, has been reported in a subset of hepatocellular carcinoma (HCC), biliary and pancreatic cancers. This suggests that BAP1 could play a role in the pathogenesis of these tumors. We assessed the frequency of BAP1 loss by immunohistochemistry in 103 hepatic, biliary and pancreatic cancers. We also assessed chromosomal alterations in the BAP1 region in the same tumors by genotyping. We identified high frequency 4/8 (50%) of BAP1 loss in intrahepatic cholangicarcinoma (ICC)...
August 2018: Cancer Genetics
https://www.readbyqxmd.com/read/29777492/redo-proximal-thoracic-aortic-surgery-challenges-and-controversies
#20
Athanasios Antoniou, Mohamad Bashir, Amer Harky, Carmelo Di Salvo
Reoperations on the proximal thoracic aorta represent a challenge. The mortality rate is at least three times higher than it is for the initial surgery and the complications after such procedures occur with disappointingly high frequency, leading to substantial morbidity and delayed recovery. This article aims to present the early and the late outcomes of these kinds of operations, to identify the causes for failure of the primary surgery, to underline the critical points during the perioperative management of those patients and finally to emphasize on the rapid evolution and advent of techniques over the last few years...
May 18, 2018: General Thoracic and Cardiovascular Surgery
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