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Optimal firing rate estimation. 总被引:1,自引:0,他引:1
We define a measure for evaluating the quality of a predictive model of the behavior of a spiking neuron. This measure, information gain per spike (Is), indicates how much more information is provided by the model than if the prediction were made by specifying the neuron's average firing rate over the same time period. We apply a maximum Is criterion to optimize the performance of Gaussian smoothing filters for estimating neural firing rates. With data from bullfrog vestibular semicircular canal neurons and data from simulated integrate-and-fire neurons, the optimal bandwidth for firing rate estimation is typically similar to the average firing rate. Precise timing and average rate models are limiting cases that perform poorly. We estimate that bullfrog semicircular canal sensory neurons transmit in the order of 1 bit of stimulus-related information per spike. 相似文献
44.
Can performance‐based financing help reaching the poor with maternal and child health services? The experience of rural Rwanda 下载免费PDF全文
Laurence Lannes Bruno Meessen Agnes Soucat Paulin Basinga 《The International journal of health planning and management》2016,31(3):309-348
More than 20 countries in Africa are scaling up performance‐based financing (PBF), but its impact on equity in access to health services remains to be documented. This paper draws on evidence from Rwanda to examine the capacity of PBF to ensure equal access to key health interventions especially in rural areas where most of the poor live. Specifically, it focuses on maternal and child health services, distinguishing two wealth groups, and uses data from a rigorous impact evaluation. Difference‐in‐difference technique is used, and different model specifications are tested: control for unobserved heterogeneity and common random error using linear probability model, seemingly unrelated regression equations, and clustering and fixed effects. Results suggest that in Rwanda, PBF improved efficiency rather than equity for most health services. We find that PBF achieved efficiency gains by improving access to health services for those easier to reach, generally the relatively more affluent. It turns out to be less effective in reaching the poorest. Our results illustrate the advantages of rigorous randomized impact evaluation data as results published earlier using a nationally representative survey (Demographic and Health Survey) were not able to capture the pro‐rich nature of the PBF scheme in Rwanda. Our paper advocates for building mechanisms targeting the vulnerable groups in PBF strategies. It also highlights the need to understand the impact of PBF together with the specific development of health insurance coverage and the organization of the health system. 相似文献
45.
Dzintars Gotham Lorenzo Moja Maarten van der Heijden Sarah Paulin Ingrid Smith Peter Beyer 《Health policy (Amsterdam, Netherlands)》2021,125(3):296-306
IntroductionThe pipeline of new antibacterials remains limited. Reasons include low research investments, limited commercial prospects, and scientific challenges. To complement existing initiatives such as research grants, governments are exploring policy options for providing new market incentives to drug developers.Materials and methodsReimbursement interventions for antibacterials in France, Germany, Sweden, US, and UK were reviewed and analysed by the authors.ResultsIn France, Germany, and the US, implemented interventions centre on providing exceptions in cost-containment mechanisms to allow higher prices for certain antibacterials. In the US, also, certain antibacterials are granted additional years of protection from generic competition (exclusivity) and faster regulatory review. The UK is piloting a model that will negotiate contracts with manufacturers to pay a fixed annual fee for ongoing supply of as many units as needed. Sweden is piloting a model that will offer manufacturers of selected antibacterials contracts that would guarantee a minimum annual revenue. A similar model of guaranteed minimal annual revenues is under consideration in the US (PASTEUR Act).ConclusionsThe UK and Sweden are piloting entirely novel procurement and reimbursement models. Existing interventions in the US, France, and Germany represent important, but relatively minor interventions. More countries should explore the use of novel models and international coordination will be important for ‘pull’ incentives to be effective. If adopted, the PASTEUR legislation in the US would constitute a significant ‘pull’ incentive. 相似文献
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Hafnia alvei in stool specimens from patients with diarrhea and healthy controls. 总被引:3,自引:2,他引:1 下载免费PDF全文
J Ridell A Siitonen L Paulin L Mattila H Korkeala M J Albert 《Journal of clinical microbiology》1994,32(9):2335-2337
We found an epidemiological association of Hafnia alvei with diarrhea, because the organism was isolated from 12 of 77 (16%) adult Finnish tourists to Morocco who developed diarrhea and from 0 of 321 tourists without diarrhea (P < 0.001). From another group of 112 adult Finnish diarrheal patients, only 2 (2%) yielded H. alvei. In contrast to some Bangladeshi strains of H. alvei, the Finnish strains were negative for the attachment-effacement lesion by an in vitro fluorescent acting staining test and also did not show homology to the Escherichia coli attachment-effacement gene (eaeA) by PCR. These results suggest that a mechanism or mechanisms other than the attachment-effacement lesion may also be involved in the association of H. alvei with diarrhea. 相似文献
48.
Mary Ann Dutton Laura C. Hohnecker Paulin M. Halle Kimberly J. Burghardt 《Journal of traumatic stress》1994,7(4):549-564
This study compared levels of violence, social support, and post-traumatic stress between battered women charged with a violent crime against an abusive partner and those seeking help from a mental health clinic. Results indicated that forensic battered women were more likely than clinical battered women to report experiencing severe violence, including sexual abuse, in their relationships. Women in the forensic sample also reported less social support and greater post-traumatic stress than women in the clinical sample. However, when social support and level of violence were accounted for, levels of general post-traumatic stress indicators (MMPI-PTSD, CR-PTSD, GSI) were no longer different between groups, although levels of specific post-traumatic stress indicators (intrusion, avoidance) remained higher for battered women in the forensic sample. Implications for understanding battered women's response to violence and their post-traumatic reactions to it are discussed. 相似文献
49.
María Laura Alberti Francisco Paulin Heidegger Mateos Toledo Martín Eduardo Fernández Fabián Matías Caro Jorge Rojas-Serrano Mayra Edith Mejía 《Reumatología clinica》2018,14(2):75-80
Objectives
To identify clinical or immunological features in patients with undifferentiated connective tissue disease (UCTD) associated interstitial lung disease (ILD), in order to group them and recognize different functional and high resolution computed tomography (HRCT) behavior.Methods
Retrospective cohort study. Patients meeting Kinder criteria for UCTD were included. We defined the following predictive variables: ‘highly specific’ connective tissue disease (CTD) manifestations (Raynaud's phenomenon, dry eyes or arthritis), high antinuclear antibody (ANA) titer (above 1: 320), and ‘specific’ ANA staining patterns (centromere, cytoplasmic and nucleolar patterns). We evaluated the following outcomes: change in the percentage of the predicted forced vital capacity (FVC%) during the follow-up period, and HRCT pattern.Results
Sixty-six patients were included. Twenty-nine (43.94%) showed at least one ‘highly specific’ CTD manifestation, 16 (28.57%) had a ‘specific’ ANA staining pattern and 29 (43.94%) high ANA titer. Patients with ‘highly specific’ CTD manifestations were younger (mean [SD] 52 years [14.58] vs 62.08 years [9.46], P < .001), were more likely men (10.34% vs 48.65%, P < .001) and showed a smaller decline of the FVC% (median [interquartile range] 1% [?1 to 10] vs -6% [?16 to ?4], P < .006). In the multivariate analysis, the presence of highly specific manifestations was associated with improvement in the FVC% (B coefficient of 13.25 [95% confidence interval, 2.41 to 24.09]). No association was observed in relation to the HRCT pattern.Conclusion
The presence of ‘highly specific’ CTD manifestations was associated with female sex, younger age and better functional behavior. These findings highlight the impact of the clinical features in the outcome of patients with UCTD ILD. 相似文献50.
R M Weintraub J M Aroesty S Paulin F H Levine J E Markis P J LaRaia S I Cohen G F Kurland 《The American journal of cardiology》1979,43(5):877-882
Of 82 patients with medically refractory unstable angina pectoris seen between October 1972 and January 1978, 60 patients underwent a combination of intraaortic balloon pump counterpulsation, cardiac catheterization and coronary revascularization. Most patients had atherosclerotic involvement of the vessels of the anterior left ventricular wall, 48 patients (80 percent) had abnormalities of left ventricular wall contraction and 22 patients (36 percent) had evidence of acute myocardial injury. One operative and one late death occurred. The perioperative infarction rate was 5 percent. Survivors, followed up for 3 to 63 months (mean 31 months), have done remarkably well; 77 percent are considered employable,and more than 90 percent are in functional class I or II. 相似文献