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Efficiency plays a crucial role in portfolio optimization. This notion is formulated by means of stochastic optimization techniques. Very often this problem is subject to partial uncertainty or incomplete information on the probability distribution and on the preferences expressed by means of the utility function. In this case both the objective function and the underlying probability measure are not known with precision. To address this kind of issues, we propose to model the notion of incomplete information by means of set-valued analysis and, therefore, we propose two different extensions of the classical model. In the first one we rely on the notion of set-valued function while the second one utilizes the notion of set-valued probability. For both of them we investigate stability properties. These results are also linked to the notion of robustness of the aforementioned problem. Finally we apply the obtained results to portfolio theory and stochastic dominance. [ABSTRACT FROM AUTHOR]

The aim of this work is to analyze some conditions for the existence of solution of a perturbed mixed variational system and that of an associated inverse problem related to the collage-based approach, both on perforated domains or domains with holes. In addition, we study the influence of the size of the holes and state some convergence results. Finally, we conduct a computational study for solving some of those inverse problems. [ABSTRACT FROM AUTHOR]

In this paper we extend the notion of stochastic efficiency and inefficiency in portfolio optimization to the case of incomplete information by means of set-valued probabilities. The notion of set-valued probability models the concept of incomplete information about the underlying probability space and the probability associated with each scenario. Unlike other approaches in literature, our notion of inefficiency is introduced by means of the Monge–Kantorovich metric. We provide some numerical examples to illustrate this approach. [ABSTRACT FROM AUTHOR]

It is now generally accepted that Euclidean-based metrics may not always adequately represent the subjective judgement of a human observer. As a result, many image processing methodologies have been recently extended to take advantage of alternative visual quality measures, the most prominent of which is the Structural Similarity Index Measure (SSIM). The superiority of the latter over Euclidean-based metrics have been demonstrated in several studies. However, being focused on specific applications, the findings of such studies often lack generality which, if otherwise acknowledged, could have provided a useful guidance for further development of SSIM-based image processing algorithms. Accordingly, instead of focusing on a particular image processing task, in this paper, we introduce a general framework that encompasses a wide range of imaging applications in which the SSIM can be employed as a fidelity measure. Subsequently, we show how the framework can be used to cast some standard as well as original imaging tasks into optimization problems, followed by a discussion of a number of novel numerical strategies for their solution. [ABSTRACT FROM AUTHOR]

Three organic compounds containing azole rings 1-benzyl-4-phenyl-1H-1,2,3-triazole (I1), 5-phenyl-3-propylisoxazole (I2), and 3,5-diphenylisoxazole (I3) were synthesized and characterized as corrosion inhibitors on galvanized steel and copper-nickel (Cu-Ni, 90/10) substrates. The three tested azole inhibitors acted as corrosion inhibitors on galvanized steel in the presence of real cooling water used as electrolyte. Electrochemical performance indicated that the presence of heteroatoms, such as N and O, with free pair electrons, the chain length, and the aromatic ring plays an important role in the capacity to inhibit corrosion of galvanized steel. 3,5-diphenylisoxazole (I3) has the best inhibition activity with jcorr of 2.04 × 10−7 (5 ppm), 7.57 × 10−8 (10 ppm), and 1.73 × 10−8 (20 ppm) A cm−2, followed by compounds I1 and I2. The synthesized compounds are comparable or even higher than the electrochemical performance of commercial inhibitor tolyltriazole (TTA, jcorr = 3.06 × 10−8 A cm−2). Conversely, for Cu-Ni (90/10) substrates, commercial TTA with 20 ppm displayed the lowest corrosion current densities (jcorr = 3.20 × 10−8 A cm−2) through a characteristic anodic pseudo-passivation; however, pits were observed after ~550 mVAg/AgCl. In contrast, the synthesized compounds tended to suppress anodic copper dissolution at positive potentials but, in the best case, displayed greater corrosion rates I3 (1.463 mils per year (MPY)), I2 (1.515 MPY), and I1 (0.677 MPY) in comparison with TTA (0.091 MPY). The low inhibition efficiency (IE) of synthesized compounds is correlated to the weak absorption on the copper surface. [ABSTRACT FROM AUTHOR]

Markowitz’s work has had a major impact on academic research and the financial industry as a whole. The main idea of his model is risk aversion of average investors and their desire to maximise the expected return with the least risk. In this paper we extend the classical Markowitz’s model by introducing a portfolio optmization model in which the underlying space of events is described in terms of a probability multimeasure. The notion of probability multimeasure allows to formalize the concept of imprecise probability measure and incomplete information. [ABSTRACT FROM AUTHOR]

Objective: Different authors hypothesized an important impact of sexual behavior on the prevalence of oral human papillomavirus (HPV) infections. In order to investigate this relationship more in detail and in contrast to most other studies, the present work focused on the population group with the highest risk for sexually transmitted infections: young and sexual active adults. Materials and methods: Three hundred and ten men and women aged 18-30 years could be recruited. After the completion of a risk-factor survey, brush smear samples for oral HPV detection were taken in every participant. Results: In 18.1 %, oral HPV could be detected. Overall, smoking ( p = 0.0074) and a high number of different sexual partners (vaginal: p = 0.0001; oral: p < 0.0001) were significantly correlated with a positive HPV testing. In case of high risk HPV infections, besides tobacco and sexual behavior, alcohol consumption showed a significant association with a positive testing ( p = 0.0212). Conclusions: Overall, the prevalence of oral HPV seems to be higher in young, sexual active adults compared to other population groups. Tobacco and alcohol may facilitate an oral HPV infection. Sexual behavior, especially oral sex practices, seems to play a crucial role in the transmission of oral HPV. Clinical relevance: The presented data, especially the association of oral high risk HPV positivity and promiscuity, may lead to improvements in the existing oral HPV prevention strategies like a HPV vaccination for both genders. [ABSTRACT FROM AUTHOR]

Copyright of Stomatologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For a metric space $(\mathbb {X},d)$ the classical Monge-Kantorovich metric d gives a distance between two probability measures on $\mathbb {X}$ which is tied to the underlying distance d on $\mathbb {X}$ in an essential way. In this paper, we extend the Monge-Kantorovich metric to signed measures and set-valued measures (multimeasures) and, in each case, prove completeness of a suitable space of these measures. Using this extension as a framework, we construct self-similar multimeasures by using an IFS-type Markov operator. [ABSTRACT FROM AUTHOR]

In the first part of this paper we show how inverse problems for differential equations can be solved using the so-called collage method. Inverse problems can be solved by minimizing the collage distance in an appropriate metric space. We then provide several numerical examples in mathematical biology. We consider applications of this approach to the following areas: population dynamics, mRNA and protein concentration, bacteria and amoeba cells interaction, tumor growth. [ABSTRACT FROM AUTHOR]

Copyright of Stomatologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We add stochastic technological progress, modelled as a geometric Brownian motion with drift, to an augmented Uzawa-Lucas growth model. Under a particular combination of parameters we derive a closed form solution to the model and analytical expressions which show that uncertainty reduces the optimal levels of consumption and increases the proportion of human capital devoted to producing new human capital. [ABSTRACT FROM AUTHOR]

Understanding the spatial and temporal variation in soil respiration within small geographic areas is essential to accurately assess the carbon budget on a global scale. In this study, we investigated the factors controlling soil respiration in an altitudinal gradient in a southern Mediterranean mixed pine–oak forest ecosystem in the north face of the Sierra de Guadarrama in Spain. Soil respiration was measured in five Pinus sylvestris L. plots over a period of 1 year by means of a closed dynamic system (LI-COR 6400). Soil temperature and water content were measured at the same time as soil respiration. Other soil physico-chemical and microbiological properties were measured during the study. Measured soil respiration ranged from 6.8 to 1.4 μmol m−2 s−1, showing the highest values at plots situated at higher elevation. Q 10 values ranged between 1.30 and 2.04, while R 10 values ranged between 2.0 and 3.6. The results indicate that the seasonal variation of soil respiration was mainly controlled by soil temperature and moisture. Among sites, soil carbon and nitrogen stocks regulate soil respiration in addition to soil temperature and moisture. Our results suggest that application of standard models to estimate soil respiration for small geographic areas may not be adequate unless other factors are considered in addition to soil temperature. [ABSTRACT FROM AUTHOR]

Introduction: Transcranial Doppler (TCD) can detect the cerebral circulation arrest (CCA) in brain death. TCD is highly specific, but less sensitive because of false-negatives accounting for up to 10%. The aim of the study was to explore the diagnostic accuracy of TCD and to determine whether it can be augmented by strategies such as the insonation of the extracranial internal carotid artery (ICA) and sequential examinations.Methods: Data of 184 patients, who met clinical criteria of brain death, observed from 1998 through 2006, were retrospectively reviewed. The study of cerebral arteries was performed through the transtemporal approach, suboccipital insonation of the vertebro-basilar system, transorbital insonation of the ICA and ophthalmic artery, and transcervical insonation of the extracranial ICA. Repeated exams were performed in cases of persistent diastolic flow.Results: The specificity of the testing was 100%, no false-positive cases were recorded. The sensitivity of conventional TCD examination was 82.1%. The insonation of the extracranial ICA increased sensitivity to 88% allowing the detection of CCA in those patients lacking temporal windows; serial examinations further increased sensitivity to 95.6%.Conclusions: The addition of insonation of the cervical ICA and of the siphon increased sensitivity of TCD. Nevertheless, a CCA flow patterns may appear later on those segments. Serial examinations, may be needed in those cases. [ABSTRACT FROM AUTHOR]

Background: The progression of HIV-1 infection towards its more advanced stages is accompanied by changes in iron metabolism and increased body iron stores. Patients and Methods: Given the ability of HIV to alter iron metabolism, we studied the principal (transferrin system) and alternative (citrate system) iron pathways in a group of 65 HIV-infected patients (symptomatic stage B1-B3) and in a group of 36 healthy seronegative individuals. We determined serum citrate levels, haptoglobin (Hp) haplotypes, expression of transferrin receptor (CD71) on cell lines infected with HIV-1 as well as iron markers including blood iron, transferrin and ferritin. Results: Our data showed decreased serum citrate levels in the HIV-infected patients compared to controls (92.9 ±± 22.4 μM/l vs 126.2 ± 29.2 μM/l; p < 0.01). In particular, the serum citrate levels negatively correlated with HIV-1 RNA copy number (mean: 2.53 ± 1.88 × 105/ml, rs = 0.70, p < 0.01) and positively correlated with CD4+ T-lymphocyte count (mean: 241 ± 168/ml, rs = 0.64, p > 0.05). Accordingly, blood iron, transferrin and red cell concentrations were lower in HIV-infected patients compared to the controls, whereas serum ferritin levels were higher in HIV-infected patients. Moreover, the Hp haplotype distribution showed significant differences only in the group of HIV-infected patients (p = 0.02; χ² test). Conclusion: Our results show that iron metabolism is altered in patients with HIV-1 infection. The alternative pathway (citrate system) is particularly affected, since when citrate levels are low, both aconitase activity and HIV-1 replication need iron. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the clinical use of radionuclide-labeled white blood cell scintigraphy in the detection of focal sepsis.Design: Prospective clinical study.Setting: A medical/surgical 12-bed intensive care unit (ICU) in a university hospital.Patients: 26 trauma and surgical patients affected by sepsis of unknown origin were studied.Measurements and Results: After the usual diagnostic approach, patients were submitted to a total body scan by using the patient's leukocytes labeled with technetium-99m (99m-Tc) HMPAO; three scintigraphy were performed within 20 h of tracer injection; the result of scan was completed with all clinical and instrumental data, including ultrasound (US) arnd computed tomography (CT), and the diagnostic efficacy was demonstrated for each patient on discharge from the ICU. The scan was able to detect 20 sites of infection; it was possible to rule out 11 suspected sites; only in two cases was the result considered to be false positive or false negative; in two cases the result was considered to be uncertain. These results show the high sensitivity (95%), specificity (91%) and accuracy (94%) of the method.Conclusions: In ICU patients with sepsis, nuclear medicine can provide additional data, as the injection of radionuclide-labeled white blood cells (WBCs) allows the imaging of sites of infection. Analysis of our results suggests that scintigraphy with 99m-Tc-labeled WBCs can be considered a useful tool in the detection of the source of infection. [ABSTRACT FROM AUTHOR]

Complement fixation (CF), indirect double-antibody sandwich (DAS) enzyme-linked immunosorbent assay (ELISA) and solid-phase immune electron microscopy (SPIEM) were compared for their ability to subgroup 73 human rotavirus (HRV) strains from infants and young children with gastroenteritis admitted to one or the other of two different hospitals of Northern Italy. By both indirect DAS ELISA and SPIEM all 73 HRV strains were classified into one or the other of two subgroups. By CF only 67 strains could be subgrouped, as six HRV-positive stools showed anticomplementary activity which could not be eliminated. Indirect DAS ELISA required subgroup-specific, unabsorbed antisera from two different animal species. For SPIEM two antisera from a single animal species were needed, but they had to be absorbed with single-shelled bovine rotavirus for HRV subgrouping to be reliable. Indirect DAS ELISA appeared to be the technique most suitable for extensive application in epidemiological studies of HRV infections by different subgroups. However, SPIEM allowed rapid subgrouping of HRV in stool specimens showing anticomplementary activity in the CF test or non-specific reactions in the ELISA test. In one area of Northern Italy the prevalence of subgroup I HRV infections was 7.8 per cent, while in another it reached 68.1 per cent in the same period. [ABSTRACT FROM AUTHOR]

The production of nitric oxide (NO) by macrophages is important for the killing of intracellular pathogens, such as Toxoplasma gondii. Gamma interferon (IFN-γ) and lipopolysaccharide stimulate NO production. The aim of this study was to investigate the importance of NO, IFN-γ and interleukin-12 (IL-12) in the host immune response in AIDS patients suffering from toxoplasmic encephalitis (TE). It was demonstrated that the production of NO, detected as nitrite/nitrate in the sera and in the cerebrospinal fluid (CSF) of 32 AIDS patients with TE, was normal. In addition, levels of IFN-γ in the sera and in the CSF of patients with TE were not increased. In contrast, serum level of IL-12 in these patients were significantly increased (6.5±7.1 pg/ml; P-0.0368), compared to the control patients (1.7±3.5 pg/ml). Furthermore, increased but not significant levels of IL-12 were also observed in the CSF of patients with TE (2.2±4.7 pg/ml; controls: 0.5±1.9 pg/ml). The results of this study indicate that reactivation or recurrence of T. gondii infection in HIV-1-infected patients is probably due to a down-regulation of IFN-γ along with a resulting non-optimal NO activity. [ABSTRACT FROM AUTHOR]

Human herpesvirus-6 (HHV-6) is the etiologic agent of roseola infantum, and has been implicated as a possible cause of encephalitis in pediatric and adult patients. A case of meningoencephalitis in an otherwise healthy, immunocompetent 59-year-old woman is described. The diagnosis of HHV-6 meningoencephalitis was confirmed by detecting viral DNA in cerebrospinal fluid collected in the acute stage of the disease by polymerase chain reaction. The patient was treated with acyclovir and recovered without any sequelae. The current knowledge of the pathophysiology, clinical course and outcome of HHV-6 meningoencephalitis in immunocompetent adult patients is also reviewed. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate nitric oxide (NO) activity in patients with uncomplicated malaria. Lipopolysaccharide and gamma interferon (IFN-γ) are potent inducers of NO by inducing production of NO synthase. NO activity was determined by measuring serum levels of nitrite/nitrate (metabolic end products of NO), and IFN-γ in patients with uncomplicated malaria, mostly caused by Plasmodium falciparum. Neither serum levels of nitrite/nitrate nor of IFN-γ were significantly increased in patients with uncomplicated malaria, especially in patients with P. falciparum infection, and in those with high parasitaemia. These results show that NO cannot play a role in uncomplicated malaria, and it is still debatable if NO production in this infection has beneficial or detrimental effects. [ABSTRACT FROM AUTHOR]

Meningeal involvement in leptospiral infection is quite common, usually mild and often overlooked. In contrast, cases of isolated involvement of the central nervous system, including aseptic meningitis, have been reported only rarely. A case of a patient with acute aseptic meningitis caused by Leptospira australis serovar bratislava is reported. This is believed to be the first report of aseptic meningitis due to Leptospira australis. This case indicates the need to consider human leptospirosis in the differential diagnosis of aseptic meningitis. [ABSTRACT FROM AUTHOR]

Copyright of Infection is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Infection is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)