scholarly journals Properties of Predictive Gain Modulation in a Dragonfly Visual Neuron

2018 ◽  
Author(s):  
Joseph M Fabian ◽  
James R Dunbier ◽  
David C O'Carroll ◽  
Steven D Wiederman
Keyword(s):  
Receptive Field ◽  
Visual Signal ◽  
Gain Modulation ◽  
Success Rates ◽  
Gain Enhancement ◽  
Input Signals ◽  
Target Detecting ◽  
Motion Detectors ◽  
Visual Neuron ◽  
Over Time

Dragonflies pursue and capture tiny prey and conspecifics with extremely high success rates. These moving targets represent a small visual signal on the retina and successful chases require accurate detection and amplification by downstream neuronal circuits. This amplification has been observed in a population of neurons called Small Target Motion Detectors (STMDs), through a mechanism we termed predictive gain modulation. As targets drift through the receptive field responses build slowly over time. This gain is modulated across the receptive field, enhancing sensitivity just ahead of the targets path, with suppression of activity elsewhere in the surround. Whilst some properties of this mechanism have been described, it is not yet known which stimulus parameters are required to generate this gain modulation. Previous work suggested that the strength of gain enhancement was predominantly determined by the duration of the targets prior path. Here we show that the predictive gain modulation is more than a sluggish build-up of gain over time. Rather, gain is dependent on both past and present parameters of the stimulus. We also describe response variability as a major challenge of target detecting neurons and propose that the predictive gain modulations role is to drive neurons into response saturation, thus minimising neuronal variability despite noisy visual input signals.

scholarly journals Clinical and echocardiographic trends in percutaneous balloon mitral valvuloplasty

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Ofir Koren ◽  
Asaf Israeli ◽  
Ehud Rozner ◽  
Nassem Darawshy ◽  
Yoav Turgeman
Keyword(s):  
Heart Failure ◽  
Medical Center ◽  
Success Rates ◽  
Mitral Valvuloplasty ◽  
Percutaneous Balloon Mitral Valvuloplasty ◽  
Developing Heart ◽  
Percutaneous Balloon ◽  
Study Population ◽  
Procedural Success ◽  
Over Time

Abstract Background The prevalence of Rheumatic Mitral Stenosis (MS) has significantly changed over the last decades. We intend to examine patient demographics, Echocardiographic characteristics, procedural success rates, and complications throughout 30-years. Methods We conducted a single-center descriptive observational study. The study population consists of patients undergone percutaneous balloon mitral valvuloplasty (PBMV) at Emek Medical Center in Israel from January 1990 to May 2019. Results Four hundred seventeen patients underwent PBMV during the study period and were eligible for the study. Age did not change significantly over time (p = 0.09). The prevalence of Male and patients who were smoking and had multiple comorbidities such as hypertension, dyslipidemia, ischemic heart disease, and chronic kidney disease became increases over time (p = 0.02, p = 0.02, p = 0.001, p = 0.01, p = 0.02, and p = 0.001, respectively). Wilkins score and all its components increased over time, and the total score was higher in females (p = 0.01). Seventy-nine (18.9%) patients had complications. The rate of complications did not change over decades. Patients with Wilkins score > 8, post-procedural MR of ≥2, and post-procedural MVA < 1.5 had the highest risk for the need of Mitral valve replacement (MVR) surgery in 2 years following PBMV (3.64, 4.03, 2.44, respectively, CI 95%, p < .0001 for all). The median time in these patients was 630 days compared to 4–5 years in the entire population. Patients with Post-procedural MR of ≥2 and post-procedural MVA < 1.5 had ten times risk for developing heart failure (HR 9.07 and 10.06, respectively, CI 95%, P < .0001). Conclusion Our research reveals trends over time in patients’ characteristics and echocardiographic features. Our study population consists of more male patients with multiple comorbidities and more complex and calcified valvular structures in the last decade. Wilkins score > 8, post-procedural MR of ≥2, and post-procedural MVA < 1.5 cm2 were in-depended predictors for the time for surgery and heart failure hospitalization.

Color properties of the motion detectors projecting to the goldfish tectum: III. Color-opponent interactions in the receptive field

2015 ◽  
Vol 14 (04) ◽  
pp. 441-454 ◽  
Author(s):  
Elena M. Maximova ◽  
Paul V. Maximov ◽  
Ilija Damjanović ◽  
Alexey T. Aliper ◽  
Anna A. Kasparson ◽  
...  
Keyword(s):  
Receptive Field ◽  
Color Properties ◽  
Motion Detectors

The Impact of Project Management Methodologies on Project Success

2019 ◽  
pp. 418-437
Author(s):  
Hazem Abdulla ◽  
Mukhtar Alhashimi ◽  
Allam Mohammed Hamdan
Keyword(s):  
Project Management ◽  
Oil And Gas ◽  
Project Success ◽  
Qualitative Interviews ◽  
Oil And Gas Industry ◽  
Success Rates ◽  
Gas Industry ◽  
Survey Responses ◽  
The Impact ◽  
Over Time

This study assessed the impact of project management methodologies (PMMs) on project success in the oil and gas industry in the Kingdom of Bahrain. It also explored the different project methodologies used along with their strengths and weaknesses. Quantitative approach with the support of qualitative interviews was used to achieve the objectives of this research. A total of 95 survey responses were received and 17 interviews were conducted. Projects in the oil and gas industry are more about safety than speed, and hence, the use of comprehensive methodologies and applying the relevant methodology elements are important for oil and gas projects. Furthermore, the companies in the oil and gas industry in Bahrain have to pay more attention to their project management methodologies and get it evolved and improved over time to achieve higher project success rates.

scholarly journals Effects of dental general anaesthesia treatment on early childhood caries: a prospective cohort study in China

BMJ Open ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. e028931 ◽  
Author(s):  
Haofeng Jiang ◽  
Lu Shen ◽  
Dan Qin ◽  
Songlin He ◽  
Jinhua Wang
Keyword(s):  
Early Childhood ◽  
Cohort Study ◽  
Oral Health ◽  
Prospective Cohort ◽  
Early Childhood Caries ◽  
Success Rates ◽  
Recurrence Rates ◽  
Dental Procedures ◽  
Dental General Anaesthesia ◽  
Over Time

ObjectivesTo evaluate the success rates of dental procedures, the recurrence rates of caries and changes in oral health-related quality of life (OHRQoL) in children following treatment for early childhood caries (ECC) under dental general anaesthesia (DGA) in Chongqing, China.DesignA single-centre prospective cohort study conducted from December 2016 to June 2017.SettingA tertiary stomatological hospital in Chongqing, China.ParticipantsA total of 159 children aged 2–5 years who received treatment for ECC under DGA were included.Main outcome measuresThe primary outcomes were the success rates of dental procedures (the number of successful procedures divided by the total number of procedures) and the recurrence rates of caries. The success and recurrence rates were evaluated by a specialised examiner. The secondary outcome was the change in children’s OHRQoL after DGA treatment, which was measured with the Early Childhood Oral Health Impact Scale (ECOHIS).ResultsOverall, 117 children (73.6%) and 101 children (63.5%) participated in 6-month and 12-month clinical examinations, respectively, and 151 children (95.0%) completed OHRQoL surveys pretreatment and at 1, 3, 6 and 12 months post-treatment. The resin composite, stainless steel crown, indirect pulp capping, pulpectomy, space maintenance and dental sealant success rates were 89.6%, 96.3%, 96.0%, 94.4%, 76.9% and 92.9%, respectively, at 6 months and 78.8%, 95.1%, 92.2%, 88.9%, 63.6% and 89.3%, respectively, at 12 months. 10 (8.5%) and 19 children (18.8%) developed recurrent caries within 6 and 12 months, respectively. Within 1 year of treatment, the total ECOHIS scores at each post-treatment time point were still significantly lower than those at pretreatment, although they had increased slowly over time.ConclusionsOverall, high success rates were obtained for the dental procedures, and the children’s OHRQoL significantly improved after treatment. However, there was a tendency towards caries relapse, and the children’s OHRQoL deteriorated over time.

The Application of Modern Metallurgical Principles And Knowledge to the Manufacture of Mokumé Gane (Wood-Grain Metal) Decorative Alloy

2004 ◽  
Vol 852 ◽  
Author(s):  
Ian T. Ferguson ◽  
Brian Derby ◽  
G. E. Thompson
Keyword(s):  
Aluminium Alloys ◽  
Success Rates ◽  
Hot Press ◽  
Visual Effects ◽  
Roll Bonding ◽  
Solid State Bonding ◽  
New Type ◽  
Wood Grain ◽  
Further Development ◽  
Over Time

ABSTRACTMokumé Gane layered metal is a 300-year old decorative metal laminate technique peculiar to the isolated culture of the Japanese Shogunate. Like many complex craft practices handed down through individual experience, the manufacture and development of Mokumé Gane has changed minimally over time. The application of contemporary metallurgical knowledge and solid state bonding techniques such as Hot Press Diffusion Bonding and Hot Roll Bonding provide for further development of Mokumé Gane: bonding success rates are improved, and manufacturing times are reduced. In addition, the range of possible metal combinations is substantially increased; 42 different combinations to date have been successfully bonded, including a new type of Mokumé Gane employing aluminium alloys. This research has allowed a very large increase in the variety of colours, patterns, and visual effects, available to contemporary metalsmiths and jewellers.

scholarly journals How stable are stop smoking practitioner success rates over time?

2014 ◽  
Vol 4 (2) ◽  
pp. 220-225 ◽  
Author(s):  
Leonie S. Brose ◽  
Robert West ◽  
Andy McEwen
Keyword(s):  
Success Rates ◽  
Stop Smoking ◽  
Over Time

scholarly journals Clinical and Echocardiographic Trends in Percutaneous Balloon Mitral Valvuloplasty

2020 ◽  
Author(s):  
Ofir Koren ◽  
Asaf Israeli ◽  
Ehud Rozner ◽  
Nassem Darawshy ◽  
Yoav Turgeman
Keyword(s):  
Standard Of Care ◽  
Complication Rates ◽  
Success Rates ◽  
Current Standard ◽  
Mitral Valvuloplasty ◽  
Patient Demographics ◽  
Percutaneous Balloon Mitral Valvuloplasty ◽  
Percutaneous Balloon ◽  
Male Patients ◽  
Over Time

Abstract Background Percutaneous balloon mitral valvuloplasty (PBMV) is the current standard of care for selected patients with rheumatic mitral stenosis. We examined trends in patient demographics, Wilkins score and additional echocardiographic characteristics, success rates, and complications over a 30-year period.Methods We conducted a retrospective observational descriptive study. The study population consists of patients hospitalized in intensive cardiac care (ICCU) due to significant symptomatic MS, from January 1990 to May 2019.Results 417 patients who underwent PBMV were eligible. Age did not change significantly over time. Male patients who were smoking and had multiple comorbidities such as hypertension, dyslipidemia, ischemic heart disease, and chronic kidney disease became more prevalence (p=0.02, p=0.02, p=0.001, p=0.01, p=0.02, and p=0.001 respectively). Wilkins score and all its components increased over time, which was higher in females (p=0.01), and was not correlated with age (p=0.95). Severe leaflets immobility (Grade 4) predicted complications (p=0.03, respectively). Wilkins over 9 successfully predicted the occurrence of complications, conversely, no efficient cutoff was found in the following decades. Wilkins score managed to predict a technically successful procedure (p=0.02), but not complications (p=0.12). Lastly, complication rates did not significantly change over the years.Conclusion Our research covers three decades of experience in PBMV and shows several trends: We see more male patients, who have multiple comorbidities. The Wilkins score increased over the years and was predictive of successful operations as opposed to complications who were predicted mainly by the leaflet mobility index.

The case for early post-vasectomy semen analysis combining small non-motile sperm and azoospermia

2018 ◽  
Vol 12 (1) ◽  
pp. 50-53
Author(s):  
Jane Hendry ◽  
Robert Small ◽  
Abdullah Zreik ◽  
Niamh Smyth ◽  
Joby Taylor
Keyword(s):  
Patient Compliance ◽  
Semen Analysis ◽  
Motile Sperm ◽  
Success Rates ◽  
Level Of Evidence ◽  
Verbal Instructions ◽  
Time Period ◽  
Sampling Protocols ◽  
The Impact ◽  
Over Time

Background: Post-vasectomy semen analysis timing and criteria guidelines have evolved over time. Through analysis of our unit’s practice of post-vasectomy semen analysis from earlier sampling protocols at 8 weeks to single sampling at 12 weeks then 16 weeks, the impact on success rates and patient compliance were assessed. In addition, the use of small numbers of non-motile sperm and azoospermia combined rates as a marker of sterility were examined. Methods: All patients who underwent vasectomy in 2011 (8 and 12-week samples), 2013 (12-week samples) and 2016 (16-week samples) were included. Patients were given written and verbal instructions explaining the sample delivery protocol and samples. χ2 Testing was used to compare patient compliance and the results of post-vasectomy semen analysis with significance set at P<0.05. Results: In total 1124 vasectomies were performed, with 21% ( N=232) of patients non-compliant with submitting samples at the requested time period. Azoospermia rates increased with a longer time to post-vasectomy semen analysis from 82% to 95%, P<0.001; however, declining compliance meant the proportion of patients given clearance remained the same (70% vs. 68%, P=0.32). Rates of small non-motile sperm declined over an increasing time to post-vasectomy semen analysis. Therefore combined azoospermia and small non-motile sperm rates remained stable over an increasing sampling time (95% vs. 99%, P=0.39). Conclusion: The use of earlier post-vasectomy semen analysis is recommended as patient compliance decreases with the time from vasectomy. When azoospermia and small non-motile sperm rates are combined the rates of success of the procedure remain the same over time therefore earlier testing at 8 weeks is feasible without compromising clearance rates. Level of evidence: Not applicable for this single centre audit.

scholarly journals Abnormal development of cerebellar-striatal circuitry in Huntington disease

Neurology ◽  
2020 ◽  
Vol 94 (18) ◽  
pp. e1908-e1915 ◽  
Author(s):  
Alexander V. Tereshchenko ◽  
Jordan L. Schultz ◽  
Joel E. Bruss ◽  
Vincent A. Magnotta ◽  
Eric A. Epping ◽  
...  
Keyword(s):  
Functional Mri ◽  
Huntington Disease ◽  
Developmental Trajectories ◽  
Abnormal Development ◽  
Compensatory Mechanisms ◽  
Functional Connections ◽  
Input Signals ◽  
History Of ◽  
Age Range ◽  
Over Time

ObjectiveTo test the hypothesis that the trajectory of functional connections over time of the striatum and the cerebellum differs between presymptomatic patients with the Huntington disease (HD) gene expansion (GE) and patients with a family history of HD but without the GE (GNE), we evaluated functional MRI data from the Kids-HD study.MethodsWe utilized resting-state, functional MRI data from participants in the Kids-HD study between 6 and 18 years old. Participants were divided into GE (CAG 36–59) and GNE (CAG <36) groups. Seed-to-seed correlations were calculated among 4 regions that provide input signals to the anterior cerebellum: (1) dorsocaudal putamen, (2) globus pallidus externa, (3) subthalamic nucleus, and (4) pontine nuclei; and 2 regions that represented output from the cerebellum: the dentate nucleus to the (1) ventrolateral thalamus and (2) dorsocaudal putamen. Linear mixed effects regression models evaluated differences in developmental trajectories of these connections over time between groups.ResultsFour of the six striatal–cerebellum correlations showed significantly different trajectories between groups. All showed a pattern where in the early age ranges (6–12 years) there was hyperconnectivity in the GE compared to the GNE, with those trajectories showing linear decline in the latter half of the age range.ConclusionThese results parallel previous findings showing striatal hypertrophy in children with GE as early as age 6. These findings support the notion of developmentally higher connectivity between the striatum and cerebellum early in the life of the child with HD GE, possibly setting the stage for cerebellar compensatory mechanisms.

Both Supplementary and Presupplementary Motor Areas Are Crucial for the Temporal Organization of Multiple Movements

1998 ◽  
Vol 80 (6) ◽  
pp. 3247-3260 ◽  
Author(s):  
Keisetsu Shima ◽  
Jun Tanji
Keyword(s):  
Waiting Time ◽  
Temporal Organization ◽  
Visual Signals ◽  
Aminobutyric Acid ◽  
Visual Signal ◽  
Reaching Movement ◽  
Impaired Memory ◽  
Sequence Of Movements ◽  
Over Time ◽  
Motor Areas

Shima, Keisetsu and Jun Tanji. Both supplementary and presupplementary motor areas are crucial for the temporal organization of multiple movements. J. Neurophysiol. 80: 3247–3260, 1998. To study the involvement of the supplementary (SMA) and presupplementary (pre-SMA) motor areas in performing sequential multiple movements that are individually separated in time, we injected muscimol, a γ-aminobutyric acid agonist, bilaterally into the part of each area that represents the forelimb. Two monkeys were trained to perform three different movements, separated by a waiting time, in four or six different orders. First, each series of movements was learned during five trials guided by visual signals that indicated the correct movements. The monkeys subsequently executed the three movements in the memorized order, without the visual signals. After the injection of muscimol (3 μl, 5 μg/μl in 10 min) into either the SMA or pre-SMA bilaterally, the animals started making errors in performing the sequence of movements correctly from memory. However, when guided with a visual signal, they could select and perform the three movements correctly. The impaired memory-based sequencing of movements worsened progressively with time until the animals could not perform the task. Yet they still could associate the visual signals with the different movements at that stage. In control experiments on two separate monkeys, we found that injections of the same amount of muscimol into either the SMA or pre-SMA did not cause problems with nonsequential reaching movement regardless of whether it was visually triggered or self-initiated. These results support the view that both the SMA and pre-SMA are crucially involved in sequencing multiple movements over time.

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