37 research outputs found

    Studi Intrusi Air Laut dengan Menggunakan Metode Resistivitas Konfigurasi Dipoledipole di Kawasan Desa Lubuk Saban Kecamatan Pantai Cermin Provinsi Sumatera Utara

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    The research detection of sea water intrusion had been performed using the electrical resistivity methods. The study was conducted in the village of Lubuk Saban, in the district of Pantai Cermin, North Sumatera Province. Taked of data using a resistivitimeter, Dipole-Dipole configuration. The obtained data are current (I) data and potential difference (V) data. Data processing is performed by using Res2dinv software, the result is in the form of 2D resistivity image of the subsurface resistivity. Rock resistivity values on the one track (a distance 25 m from the beach) ranged between 1,08 Ω .m – 116 Ω .m, the second track (a distance 34 m from the beach) ranged from 4,54 Ω m – 71,5 Ω m and the third track (a distance 44 m from the beach) ranged between 0,152 Ω m – 53,1 Ω m. Interpreted data showed that the intrusion of the sea water has been found in the village of Lubuk saban with the resistivity value of rocks ranged from 0,5 to 5 Ω m

    Studi Intrusi Air Laut dengan Menggunakan Metode Resistivitas Konfigurasi Dipoledipole di Kawasan Desa Lubuk Saban Kecamatan Pantai Cermin Provinsi Sumatera Utara

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    The research detection of sea water intrusion had been performed using the electrical resistivity methods. The study was conducted in the village of Lubuk Saban, in the district of Pantai Cermin, North Sumatera Province. Taked of data using a resistivitimeter, Dipole-Dipole configuration. The obtained data are current (I) data and potential difference (V) data. Data processing is performed by using Res2dinv software, the result is in the form of 2D resistivity image of the subsurface resistivity. Rock resistivity values on the one track (a distance 25 m from the beach) ranged between 1,08 Ω .m – 116 Ω .m, the second track (a distance 34 m from the beach) ranged from 4,54 Ω m – 71,5 Ω m and the third track (a distance 44 m from the beach) ranged between 0,152 Ω m – 53,1 Ω m. Interpreted data showed that the intrusion of the sea water has been found in the village of Lubuk saban with the resistivity value of rocks ranged from 0,5 to 5 Ω m

    A Method for the Generation of Ectromelia Virus (ECTV) Recombinants: In Vivo Analysis of ECTV vCD30 Deletion Mutants

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    Ectromelia virus (ECTV) is the causative agent of mousepox, a lethal disease of mice with similarities to human smallpox. Mousepox progression involves replication at the initial site of infection, usually the skin, followed by a rapid spread to the secondary replicative organs, spleen and liver, and finally a dissemination to the skin, where the typical rash associated with this and other orthopoxviral induced diseases appears. Case fatality rate is genetically determined and reaches up to 100% in susceptible mice strains. Like other poxviruses, ECTV encodes a number of proteins with immunomodulatory potential, whose role in mousepox progression remains largely undescribed. Amongst these is a secreted homologue of the cellular tumour necrosis factor receptor superfamily member CD30 which has been proposed to modulate a Th1 immune response in vivo

    GM-CSF Production Allows the Identification of Immunoprevalent Antigens Recognized by Human CD4+ T Cells Following Smallpox Vaccination

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    The threat of bioterrorism with smallpox and the broad use of vaccinia vectors for other vaccines have led to the resurgence in the study of vaccinia immunological memory. The importance of the role of CD4+ T cells in the control of vaccinia infection is well known. However, more CD8+ than CD4+ T cell epitopes recognized by human subjects immunized with vaccinia virus have been reported. This could be, in part, due to the fact that most of the studies that have identified human CD4+ specific protein-derived fragments or peptides have used IFN-γ production to evaluate vaccinia specific T cell responses. Based on these findings, we reasoned that analyzing a large panel of cytokines would permit us to generate a more complete analysis of the CD4 T cell responses. The results presented provide clear evidence that TNF-α is an excellent readout of vaccinia specificity and that other cytokines such as GM-CSF can be used to evaluate the reactivity of CD4+ T cells in response to vaccinia antigens. Furthermore, using these cytokines as readout of vaccinia specificity, we present the identification of novel peptides from immunoprevalent vaccinia proteins recognized by CD4+ T cells derived from smallpox vaccinated human subjects. In conclusion, we describe a “T cell–driven” methodology that can be implemented to determine the specificity of the T cell response upon vaccination or infection. Together, the single pathogen in vitro stimulation, the selection of CD4+ T cells specific to the pathogen by limiting dilution, the evaluation of pathogen specificity by detecting multiple cytokines, and the screening of the clones with synthetic combinatorial libraries, constitutes a novel and valuable approach for the elucidation of human CD4+ T cell specificity in response to large pathogens

    Strategies for preventing group B streptococcal infections in newborns: A nation-wide survey of Italian policies

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    Gaussian approximation for bias reduction in Q-learning

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    Temporal-Difference off-policy algorithms are among the building blocks of reinforcement learning (RL). Within this family, Q-Learning is arguably the most famous one, which has been widely studied and extended. The update rule of Q-learning involves the use of the maximum operator to estimate the maximum expected value of the return. However, this estimate is positively biased, and may hinder the learning process, especially in stochastic environments and when function approximation is used. We introduce the Weighted Estimator as an effective solution to mitigate the negative effects of overestimation in Q-Learning. The Weighted Estimator estimates the maximum expected value as a weighted sum of the action values, with the weights being the probabilities that each action value is the maximum. In this work, we study the problem from the statistical perspective of estimating the maximum expected value of a set of random variables and provide bounds to the bias and the variance of the Weighted Estimator, showing its advantages over other estimators present in literature. Then, we derive algorithms to enable the use of the Weighted Estimator, in place of the Maximum Estimator, in online and batch RL, and we introduce a novel algorithm for deep RL. Finally, we empirically evaluate our algorithms in a large set of heterogeneous problems, encompassing discrete and continuous, low and high dimensional, deterministic and stochastic environments. Experimental results show the effectiveness of the Weighted Estimator in controlling the bias of the estimate, resulting in better performance than representative baselines and robust learning w.r.t. a large set of diverse environments

    Functional and radiological outcome of anterior retroperitoneal versus posterior transforaminal interbody fusion in the management of single-level lumbar degenerative disease

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    OBJECTIVE In this study the authors compared the anterior lumbar interbody fusion (ALIF) and posterior transforaminal lumbar interbody fusion (TLIF) techniques in a homogeneous group of patients affected by single-level L5-S1 degenerative disc disease (DDD) and postdiscectomy syndrome (PDS). The purpose of the study was to analyze perioperative, functional, and radiological data between the two techniques. METHODS A retrospective analysis of patient data was performed between 2015 and 2018. Patients were clustered into two homogeneous groups (group 1 = ALIF, group 2 = TLIF) according to surgical procedure. A statistical analysis of clinical perioperative and radiological findings was performed to compare the two groups. A senior musculoskeletal radiologist retrospectively revised all radiological images. RESULTS Seventy-two patients were comparable in terms of demographic features and surgical diagnosis and included in the study, involving 32 (44.4%) male and 40 (55.6%) female patients with an average age of 47.7 years. The mean follow-up duration was 49.7 months. Thirty-six patients (50%) were clustered in group 1, including 31 (86%) with DDD and 5 (14%) with PDS. Thirty-six patients (50%) were clustered in group 2, including 28 (78%) with DDD and 8 (22%) with PDS. A significant reduction in surgical time (107.4 vs 181.1 minutes) and blood loss (188.9 vs 387.1 ml) in group 1 (p < 0.0001) was observed. No significant differences in complications and reoperation rates between the two groups (p = 0.561) was observed. A significant improvement in functional outcome was observed in both groups (p < 0.001), but no significant difference between the two groups was found at the last follow-up. In group 1, a faster median time of return to work (2.4 vs 3.2 months) was recorded. A significant improvement in L5-S1 postoperative lordosis restoration was registered in the ALIF group (9.0 vs 5.0, p = 0.023). CONCLUSIONS According to these results, interbody fusion is effective in the surgical management of discogenic pain. Even if clinical benefits were achieved earlier in the ALIF group (better scores and faster return to work), both procedures improved functional outcomes at last follow-up. The ALIF group showed significant reduction of blood loss, shorter surgical time, and better segmental lordosis restoration when compared to the TLIF group. No significant differences in postoperative complications were observed between the groups. Based on these results, the ALIF technique enhances radiological outcome improvement in spinopelvic parameters when compared to TLIF in the management of adult patients with L5-S1 DDD

    Dealing with interdependencies and uncertainty in multi-channel advertising campaigns optimization

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    In 2017, Internet ad spending reached 209 billion USD worldwide, while, e.g., TV ads brought in 178 billion USD. An Internet advertising campaign includes up to thousands of sub-campaigns on multiple channels, e.g., search, social, display, whose parameters (bid and daily budget) need to be optimized every day, subject to a (cumulative) budget constraint. Such a process is often unaffordable for humans and its automation is crucial. As also shown by marketing funnel models, the sub-campaigns are usually interdependent, e.g., display ads induce awareness, increasing the number of impressions-and, thus, also the number of conversions-of search ads. This interdependence is widely exploited by humans in the optimization process, whereas, to the best of our knowledge, no algorithm takes it into account. In this paper, we provide the first model capturing the sub-campaigns interdependence. We also provide the IDIL algorithm, which, employing Granger Causality and Gaussian Processes, learns from past data, and returns an optimal stationary bid/daily budget allocation. We prove theoretical guarantees on the loss of IDIL w.r.t. the clairvoyant solution, and we show empirical evidence of its superiority in both realistic and real-world settings when compared with existing approaches

    Functional and radiological outcome of anterior retroperitoneal versus posterior transforaminal interbody fusion in the management of single-level lumbar degenerative disease

    No full text
    OBJECTIVE In this study the authors compared the anterior lumbar interbody fusion (ALIF) and posterior transforaminal lumbar interbody fusion (TLIF) techniques in a homogeneous group of patients affected by single-level L5-S1 degenerative disc disease (DDD) and postdiscectomy syndrome (PDS). The purpose of the study was to analyze perioperative, functional, and radiological data between the two techniques. METHODS A retrospective analysis of patient data was performed between 2015 and 2018. Patients were clustered into two homogeneous groups (group 1 = ALIF, group 2 = TLIF) according to surgical procedure. A statistical analysis of clinical perioperative and radiological findings was performed to compare the two groups. A senior musculoskeletal radiologist retrospectively revised all radiological images. RESULTS Seventy-two patients were comparable in terms of demographic features and surgical diagnosis and included in the study, involving 32 (44.4%) male and 40 (55.6%) female patients with an average age of 47.7 years. The mean follow-up duration was 49.7 months. Thirty-six patients (50%) were clustered in group 1, including 31 (86%) with DDD and 5 (14%) with PDS. Thirty-six patients (50%) were clustered in group 2, including 28 (78%) with DDD and 8 (22%) with PDS. A significant reduction in surgical time (107.4 vs 181.1 minutes) and blood loss (188.9 vs 387.1 ml) in group 1 (p < 0.0001) was observed. No significant differences in complications and reoperation rates between the two groups (p = 0.561) was observed. A significant improvement in functional outcome was observed in both groups (p < 0.001), but no significant difference between the two groups was found at the last follow-up. In group 1, a faster median time of return to work (2.4 vs 3.2 months) was recorded. A significant improvement in L5-S1 postoperative lordosis restoration was registered in the ALIF group (9.0 vs 5.0, p = 0.023). CONCLUSIONS According to these results, interbody fusion is effective in the surgical management of discogenic pain. Even if clinical benefits were achieved earlier in the ALIF group (better scores and faster return to work), both procedures improved functional outcomes at last follow-up. The ALIF group showed significant reduction of blood loss, shorter surgical time, and better segmental lordosis restoration when compared to the TLIF group. No significant differences in postoperative complications were observed between the groups. Based on these results, the ALIF technique enhances radiological outcome improvement in spinopelvic parameters when compared to TLIF in the management of adult patients with L5-S1 DDD

    The use of stereotaxic cytology in the diagnosis of non-palpable breast lesions. Personal experience

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    Background and aims. The increasingly frequent use of mammography for the early diagnosis of breast cancer and the consequent identification of mammary lesions at a preclinical stage raises the fundamental problem of the differential diagnosis between non-suspected non-palpable lesions (NPL) which can therefore be monitored over time and suspected NPL or definite carcinoma requiring histological confirmation and surgical biopsy. The diagnostic accuracy of mammography alone is not sufficiently high to differentiate benign lesions from malignant or strongly suspected ones. The use of surgical biopsy in the event of suspected NPL could be significantly reduced by the use of stereotaxic cytology which would improve the diagnostic accuracy of mammography. Methods. The study refers to 72 suspected NPL undergoing surgical biopsy after having performed stereotaxic cytology on a sample taken with a dedicated mammographic device (Mammotest- TRC). Results. The rate of inadequate samples for correct cytological evaluation was 16.1%. Of the 72 NPL undergoing surgical biopsy, 40 (55.5%) were found to be carcinomas and 32 (44.5%) were benign lesions. The sensitivities of mammography alone and cytology alone in identifying infraclinical breast carcinoma were respectively 0.85 and 0.95. If the results of the two methods were evaluated together, the level of sensitivity was 0.98. Conclusions. The use of stereotaxic cytology enables a marked improvement to be achieved in the diagnostic accuracy of mammography for the identification of suspected NPL to undergo surgical biopsy, notably reducing the cost of biopsy (number of benign lesions for each carcinoma diagnosed) and consequent discomfort for patients
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