890 research outputs found

    Core-competitive Auctions

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    One of the major drawbacks of the celebrated VCG auction is its low (or zero) revenue even when the agents have high value for the goods and a {\em competitive} outcome could have generated a significant revenue. A competitive outcome is one for which it is impossible for the seller and a subset of buyers to `block' the auction by defecting and negotiating an outcome with higher payoffs for themselves. This corresponds to the well-known concept of {\em core} in cooperative game theory. In particular, VCG revenue is known to be not competitive when the goods being sold have complementarities. A bottleneck here is an impossibility result showing that there is no auction that simultaneously achieves competitive prices (a core outcome) and incentive-compatibility. In this paper we try to overcome the above impossibility result by asking the following natural question: is it possible to design an incentive-compatible auction whose revenue is comparable (even if less) to a competitive outcome? Towards this, we define a notion of {\em core-competitive} auctions. We say that an incentive-compatible auction is α\alpha-core-competitive if its revenue is at least 1/α1/\alpha fraction of the minimum revenue of a core-outcome. We study the Text-and-Image setting. In this setting, there is an ad slot which can be filled with either a single image ad or kk text ads. We design an O(lnlnk)O(\ln \ln k) core-competitive randomized auction and an O(ln(k))O(\sqrt{\ln(k)}) competitive deterministic auction for the Text-and-Image setting. We also show that both factors are tight

    Post-Mortem Immunohistochemical Evidence of β2-Adrenergic Receptor Expression in the Adrenal Gland

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    The evidence from post-mortem biochemical studies conducted on cortisol and catecholamines suggest that analysis of the adrenal gland could provide useful information about its role in human pathophysiology and the stress response. Authors designed an immunohistochemical study on the expression of the adrenal β2-adrenergic receptor (β2-AR), a receptor with high-affinity for catecholamines, with the aim to show which zones it is expressed in and how its expression differs in relation to the cause of death. The immunohistochemical study was performed on adrenal glands obtained from 48 forensic autopsies of subjects that died as a result of different pathogenic mechanisms using a mouse monoclonal β2-AR antibody. The results show that immunoreactivity for β2-AR was observed in all adrenal zones. Furthermore, immunoreactivity for β2-AR has shown variation in the localization and intensity of different patterns in relation to the original cause of death. To the best of our knowledge, this is the first study that demonstrates β2-AR expression in the human cortex and provides suggestions on the possible involvement of β2-AR in human cortex hormonal stimulation. In conclusion, the authors provide a possible explanation for the observed differences in expression in relation to the cause of death

    Immunofluorescence evaluation of Myf5 and MyoD in masseter muscle of unilateral posterior crossbite patients

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    A unilateral posterior crossbite is a malocclusion where the low activity of the affected masseter muscle is compensated by the contralateral muscle hypertrophy. It is still unknown if, in the same condition, myogenesis with new fibre formation takes place. Aim: the aim of the present study was to evaluate the expression of myogenesis markers, such as Myf5 and MyoD, in masseter muscles of unilateral posterior crossbite patients. Materials and methods: biopsies from fifteen surgical patients with unilateral posterior crossbites have been analysed by immunofluorescence reactions. The results show the expression of Myf5 and MyoD in the contralateral muscle but not in the ipsilateral one. Moreover, statistical analysis shows the higher number of satellite cells in the contralateral side if compared to the ipsilateral one. Conclusions: these results suggest that in contralateral muscle, hyperplastic events take place, as well as hypertrophy

    Cosmetics for acne: indications and recommendations for an evidence-based approach.

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    AIM: The aim of this review was to evaluate, by a thorough revision of the literature, the true efficacy of currently available topic and systemic cosmetic acne agents. METHODS: The efficacy of currently available cosmetic acne agents has been retrospectively evaluated via thorough revision of the literature on matched electronic databases (PubMed). All retrieved studies, either randomized clinical trials or clinical trials, controlled or uncontrolled were considered. RESULTS: Scientific evidence suggests that most cosmetic products for acne may enhance the clinical outcome. Cleansers should be indicated to all acne patients; those containing benzoyl peroxide or azelaic/salicylic acid/triclosan show the best efficacy profile. Sebum-controlling agents containing nicotinamide or zinc acetate may minimize excessive sebum production. Cosmetics with antimicrobial and anti-inflammatory substances such as, respectively, ethyl lactate or phytosphingosine and nicotinamide or resveratrol, may speed acne recovery. Topical corneolytics, including retinaldehyde/glycolic acid or lactic acid, induce a comedolytic effect and may also facilitate skin absorption of topical drugs. Finally, the use of specific moisturizers should be strongly recommended in all acne patients. CONCLUSION: Cosmetics, if correctly prescribed, may improve the performance of the therapy, whereas wrong procedures and/or inadequate cosmetics may worsen acne. Cosmetological recommendations may allow clinicians to make informed decisions about the role of various cosmetics and to indentify the appropriate indications and precautions. The choice of the most effective product should take into consideration the ongoing pharmacological therapy and acne type/severity as well

    Sb-SnO2-Nanosized-Based Resistive Sensors for NO2 Detection

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    A study over Sb-promoted tin oxide nanopowders for sensing applications is reported. nanopowders pure and promoted with 5 wt% of antimony were prepared by wet chemical methods and widely characterized by TEM, XRD, and XPS techniques. Thick film resistive sensors were fabricated by depositing the synthesized nanopowders by drop-coating on interdigited alumina substrates. The sensing characteristics of the pure and Sb-promoted sensors for the monitoring of trace level of were studied. The response of the sensors to water vapor was also investigated, revealing that Sb acts favorably eliminating the interference of humidity

    Salicylic Acid Peel Incorporating Triethyl Citrate and Ethyl Linoleate in the Treatment of Moderate Acne: A New Therapeutic Approach.

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    BACKGROUND: Acne affects many adolescents. Conventional therapy often results in side effects and poor adherence, and the treatment does not consider the psychological effect of acne on patients, which is comparable with that of disabling diseases. OBJECTIVES: To evaluate the efficacy and tolerability of a peel (30% salicylic acid, triethyl citrate and ethyl linoleate) combined with a home therapy with three topical agents (triethyl citrate, ethyl linoleate and salicylic acid 0.5% cream, lotion) in moderate acne of the face. DESIGN: Prospective, observational, multicenter, open-label, postmarketing, phase IV study. METHODS: Patients were assessed by comparing Global Acne Grading System (GAGS) score and total lesion count from 15 days before the first peel (T-15 ), after four salicylic peels (every 10 ± 2 days (T0 , T10 , T20 , T30 ), and 20 days after of the end of the study (T50 ). This treatment was associated to a home therapy. RESULTS: Fifty-three patients completed the study. The average GAGS score fell 49% between T-15 and T50 (p < .001). No patient withdrew for adverse events. CONCLUSIONS: This therapy was effective and well-tolerated in all cases. Chemo-exfoliation sessions ensured the continuous monitoring of clinical results and improved patient quality of life

    Experience of a tertiary referral center in managing bladder cancer in conjunction with neurogenic bladder

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    Study design: Case series. Objectives: The aim of this study was to present our experience with the management of bladder cancer (BCa) in individuals followed for neurogenic bladder (NB). Setting: An Italian tertiary referral center for NB. Methods: We retrospectively collected all pre-operative, intra-operative, and post-operative data of our NB cases with BCa, diagnosed from 2004 to 2019. Results: We included ten cases: eight with acquired spinal cord injury (SCI) and two with myelomeningocele (MMC). Considering individuals with acquired SCI, the median age at BCa diagnosis and time since SCI were 53 and 34 years, respectively. One out of seven cases had positive urine cytology. All cases underwent a radical cystectomy, diagnosing squamous cell carcinoma (SCC) and transitional cell carcinoma in 60 and 40% cases, respectively. Surgical-related complications occurred after 90% procedures. Three out of eight individuals with acquired SCI died 2, 12, and 80 months after the diagnosis. Both individuals with MMC presented no evidence of disease after 24 and 27 months. Conclusions: BCa in individuals with NB proved to be associated with a diagnosis at an advanced stage and a high rate of surgical complications. In this population we advocate annual genitourinary ultrasound exam and urine cytology, and cystoscopy in all cases of macrohematuria. Considering the low accuracy of urine cytology and the difficult-to-interpret inflamed bladder walls at cystoscopy in NB, a patient-tailored follow-up schedule based on specific risk factors (e.g., smoking status, indwelling urinary catheter) is mandatory to diagnose and treat BCa at an early stage

    Mediterranean Diet as a Shield against Male Infertility and Cancer Risk Induced by Environmental Pollutants: A Focus on Flavonoids

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    The role of environmental factors in influencing health status is well documented. Heavy metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, dioxins, pesticides, ultrafine particles, produced by human activities put a strain on the body’s entire defense system. Therefore, together with public health measures, evidence-based individual resilience measures are necessary to mitigate cancer risk under environmental stress and to prevent reproductive dysfunction and non-communicable diseases; this is especially relevant for workers occupationally exposed to pollutants and/or populations residing in highly polluted areas. The Mediterranean diet is characterized by a high intake of fruits and vegetables rich in flavonoids, that can promote the elimination of pollutants in tissues and fluids and/or mitigate their effects through different mechanisms. In this review, we collected evidence from pre-clinical and clinical studies showing that the impairment of male fertility and gonadal development, as well as cancers of reproductive system, due to the exposure of organic and inorganic pollutants, may be counteracted by flavonoids
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