Stability of synchronization in simplicial complexes.

Various systems in physics, biology, social sciences and engineering have been successfully modeled as networks of coupled dynamical systems, where the links describe pairwise interactions. This is, however, too strong a limitation, as recent studies have revealed that higher-order many-body interactions are present in social groups, ecosystems and in the human brain, and they actually affect the emergent dynamics of all these systems. Here, we introduce a general framework to study coupled dynamical systems accounting for the precise microscopic structure of their interactions at any possible order. We show that complete synchronization exists as an invariant solution, and give the necessary condition for it to be observed as a stable state. Moreover, in some relevant instances, such a necessary condition takes the form of a Master Stability Function. This generalizes the existing results valid for pairwise interactions to the case of complex systems with the most general possible architecture.

Support practices by an interdisciplinary team in a palliative-care unit for relatives of patients in agonal phase.

BACKGROUND: In the absence of extant recommendations, the aim of this study was to formalise support practices used by an interdisciplinary team in a palliative-care unit (PCU) for the relatives of patients in the agonal phase preceding death. The secondary objective was to understand the expectations of relatives during this phase in terms of the support provided by professionals and volunteers. METHODS: Thirty-two people took part in this study; all were interviewed through focus groups (FGs). Each FG comprised one category of individuals working in the PCU: nurses, care- assistants, doctors, psychologists, other professionals, palliative-care volunteers, and relatives. Groups were surveyed using an interview guide, and the interviews were recorded and transcribed to enable identification and characterization of all practices. Care practices were classified into four categories: current consensual practices (i.e. performed by all team members), occasional consensual practices, non-consensual practices (performed by one or a few participants), and practices to be developed. RESULTS: In total, 215 practices were mentioned by professionals and palliative-care volunteers: 150 current consensual practices, 48 occasional consensual practices, 1 non-consensual practice, 16 practices yet to be developed, and 29 practices for relatives. Many practices were mentioned by different categories of participants; thus, after cross-checking, the number of practices decreased from 215 to 52. A list of practices deemed desirable by all was drawn up and then validated by the entire interprofessional team. These practices were organised around four themes: providing care and ensuring comfort; communicating, informing, and explaining; interacting; and mobilising interdisciplinary skills. CONCLUSIONS: These results underline the importance of the quality of care provided to patients, the attention given to the relatives themselves, and they highlight the importance of the helping relationship. Following this study, which established a list of varied practices aimed at supporting the relatives of patients in agonal phase, it will be important to set up a broader study seeking to establish a consensus on these practices with an interprofessional group of experts from other PCUs using broad surveys and an adapted methodology. Such studies will make it possible to develop training modules for teams working with relatives.

Alterations in comprehensive geriatric assessment decrease survival of elderly patients with cancer.

INTRODUCTION: A comprehensive geriatric assessment (CGA) evaluating several domains of health is recommended for elderly patients with cancer. Effects of altered domains on the risk of death in this population need to be clarified. The aim of this study was to estimate the independent association of each CGA domain to overall survival (OS). METHOD: Patients included in the ONCODAGE cohort completed a CGA at baseline. Cox models (one per domain) estimated the hazard ratio (HR) of death for each CGA domain. Directed Acyclic Graphs (DAGs) selected specific sets of adjustment factors for each model. RESULTS: The analysis included 1264 patients (mean age: 78 years, women: 70%). Median follow-up was 5.2 years, and 446 patients died. Each altered domain had a detrimental effect on survival, sometimes dependent on gender, age, education or time from inclusion. Nutritional status had a time-varying effect, with higher mortality rates if altered only within the first 3 years of follow-up. In case of altered mobility, the risk of death was higher only for the youngest patients and, in case of altered autonomy, only for the youngest women. An altered neurological state led to higher mortality rates; this effect increased with the level of education. Patients with altered psychological status or more than four comorbidities at baseline had also higher mortality rates. CONCLUSIONS: Patients with an altered CGA domain have a higher risk of death than those without any alteration. The effect of some alterations is different in some subgroups or at a given time of the treatments.

Validation of the Behavioural Observation Scale 3 for the evaluation of pain in adults.

BACKGROUND: Many behavioural scales are available to assess pain but none are suitable for a quick evaluation of non-sedated and non-geriatric adults. The Behavioural Observation Scale 3 (BOS-3) is short, composed of five items. This study examined its feasibility and diagnostic performances. METHODS: Adult patients were included from medical and surgical departments of the University Hospital of Bordeaux. In a cross-sectional study, BOS-3 was compared to Numerical Rate Scale (NRS) with communicating patients (CP) and Behavioural Scale for the Elderly Person (ECPA2) with non-communicating patients (NCP). Each time, BOS-3 and reference scale were performed by an internal caregiver and an external expert. RESULTS: We included 447 patients: 395 communicating and 52 non-communicating. All patients were assessed by the BOS-3 and the reference test. All BOS-3 were carried out in less than one minute with only four missing data. Its reproducibility (ICC = 0.77 [95% CI 0.73-0.81] with CP and 0.93 [95% CI 0.89-0.97] with NCP) and its internal consistency (Cronbach α = 0.67 with CP and 0.70 with NCP) were good. In non-communicating patients, ROC analysis set a threshold at 3 on 10. Sensitivity was 0.87 [95% CI 0.77-0.96], specificity 0.97 [95% CI 0.93-1.00], positive predictive value 0.93 [95% CI 0.86-0.99] and negative predictive value 0.95 [95% CI 0.89-1.00]. In communicating patients, sensitivity decreased to 0.34 [95% CI 0.28-0.38] but specificity reached 0.96 [95% CI 0.94-0.98] and positive predictive value 0.75 [95% CI 0.70-0.79]. CONCLUSIONS: BOS-3 had good metrological properties in non-communicating adults. With communicating patients, a positive BOS-3 could be an additional tool to confirm pain, when underestimated on the NRS. SIGNIFICANCE: This study describes the diagnostic performances of a behavioral pain assessment scale designed for non-geriatric and non-sedated adults. The results show its validity in non-communicating patients and suggest its usefulness as an ancillary tool in communicating patients in whom simple numerical scales are often insufficient.

Anal human papillomavirus in HIV-uninfected men who have sex with men: incidence and clearance rates, duration of infection, and risk factors.

Little is known regarding the natural history of anal human papillomavirus (HPV) infection. We aimed to evaluate incidence and clearance rates, their risk factors, and duration of anal HPV infection in HIV-uninfected men who have sex with men (MSM). A longitudinal study was conducted. Anal samples were analysed using the Linear Array HPV Genotyping test. Incidence and clearance rates, and corresponding risk factors, were estimated using a two-state Markov model. Overall, 155 MSM (median age 33.4 years) attending the largest sexually transmitted infection (STI) centre in Rome, Italy, were followed for a median of 12.2 months (Q1-Q3: 7.0-18.1). Incidence and clearance rates for any HPV were 85.6 (95% CI: 58.4-125.4) and 35.6 (95% CI: 24.7-51.5) × 1000 person-months, respectively; the median duration of infection was 9.4 months (Q1-Q3: 7.5-12.1). Receptive anal sex emerged as the only risk factor for the acquisition of any HPV (Hazard Ratio, HR = 2.65, 95% CI: 1.16-6.06). The incidence rates for carcinogenic and non-carcinogenic types were 42.3 (95% CI: 29.2-61.4) and 29.2 (95% CI: 19.5-43.7) × 1000 person-months, respectively (p = 0.13); their clearance rates were 62.9 (95% CI: 45.1-87.7) and 65.7 (95% CI: 47.4-91.0) × 1000 person-months, respectively (p = 0.83). HPV16 showed the lowest clearance rate among carcinogenic types (59.7 × 1000 person-months), and a duration of infection of 16.8 months. In conclusion, a higher incidence rate was observed for carcinogenic compared to non-carcinogenic HPV types, although the difference was not significant. HPV16 emerged as the type with the longest duration of infection and the lowest clearance rate among carcinogenic types.

Efficacy of an emollient dermoprotective cream in the treatment of elderly skin affected by xerosis.

AIM: Xerosis cutis is a frequent condition in the elderly and the topical treatments are aimed to maintain a balance between the physiological components of the epidermis and an optimal moisturization. The aim was to evaluate the efficacy of a dermoprotective cream, glycerol and paraffin-based, in the treatment of individuals affected by senile xerosis. METHODS: The patients were recruited at the Professional Dermatology and Allergology Outpatient Clinic of the San Gallicano Dermatological Institute of Rome, between 1st January 2013 and 30th September 2014. To assess the efficacy of the cream, two different areas of treatment were identified in each patient upper the limbs. All patients were staged at baseline (T0) and evaluated after 14 days (T1) and 28 days (T2) of topical treatment, using five clinical parameters: scaling, sensation of skin tightness, presence of fissuring and excoriations from scratching and erythema. The itching degree was also evaluated using a 10-steps analogical scale. RESULTS: Fifty patients with xerosis, 25 with a severe and 25 with a moderate form, over 60 were recruited and evaluated. Median age was 65 years (IQR=61-70). After 28 day of topical administration of the cream, the 54.0% of patients showed the absence of signs of xerosis, the 44.0% a mild form and the 2.0% (one patient) a moderate form. Consistently, a progressive and significative reduction of itching and transepidermal water loss (TEWL), and an improvement in skin hydration was also measured. A good profile of tolerability and no episodes of undesirable side effects, was also observed. CONCLUSION: The topical daily use of a cream glycerol and paraffin-based, seem to able to control the xerosis in elderly patients, with a significant reduction of all associated signs and symptoms. Further additional data should be collected to better confirm the role of the topical treatment in the control of disease.

Forgetting what you have checked: a link between working memory impairment and checking behaviors in obsessive-compulsive disorder.

BACKGROUND: Compulsive checking behaviors are common in obsessive-compulsive disorder (OCD). Several authors have suggested that these checking rituals could be related to memory deficits. Our aim was to test whether patients with OCD show working memory impairment in relation to their checking behavior. METHODS: We evaluated the verbal and visuospatial components of patients' and controls' working memory using the reading span and backward location span tests. Checking behaviors were measured by recording participants' eye movements during an image comparison task using a non-invasive, infra-red TOBII 1750 eyetracker. Participants were seated, head-free, in a natural position in front of the eyetracker screen where the images were displayed. RESULTS: Patients with OCD made more gaze moves to compare images than controls. Both patients' working memory spans were reduced, and the patients' deficit in the comparison task was negatively related to their working memory spans. CONCLUSIONS: This work demonstrates that checking behavior in OCD is linked to a general reduction of the patients' verbal and visuospatial working memory span.

Remote synchronization in star networks.

We study phase synchronization in a network motif with a starlike structure in which the central node's (the hub's) frequency is strongly detuned against the other peripheral nodes. We find numerically and experimentally a regime of remote synchronization (RS), where the peripheral nodes form a phase synchronized cluster, while the hub remains free with its own dynamics and serves just as a transmitter for the other nodes. We explain the mechanism for this RS by the existence of a free amplitude and also show that systems with a fixed or constant amplitude, such as the classic Kuramoto phase oscillator, are not able to generate this phenomenon. Further, we derive an analytic expression which supports our explanation of the mechanism.

Double blind clinical trial in a series of 115 patients with seborrheic dermatitis: prevention of relapses using a topical modulator of Toll like receptor 2.

AIM: Seborrheic dermatitis is a chronic inflammatory disease aggravated by Malassezia species. Toll-like receptors (TLR) are part of innate immune system that can be activated by yeasts. Previous studies showed that an association of Umbelliferae extract with a lipid (TLR2-Regul™) decreases the IL-8 expression in human skin in contact with M. furfur. The aim of this study was to assess the activity of a topical formulated with TLR2-Regul™ in the prevention of seborrheic dermatitis (SD) relapses. METHODS: Immune-competent SD adult patients were treated for SD (topical imidazoles or steroids). Cleared patients were randomized and received a topical containing TLR2-Regul™ (A) or its vehicle (B). Erythema, scales and pruritus were assessed during two months. RESULTS: The study included 115 patients, mean age 43.4, sex ratio m/f 1.5. At week 4 the relapse rate was 26% (N.=15) in group A and 43% (N.=25) in group B. At W8 the relapse rate was 21% (N.=12) in group A and 40% (N.=23) (P=0.0309). CONCLUSION: In this series of 115 adults with seborrheic dermatitis, patients treated with a topical containing TLR-Regul™ showed a significantly less relapse rate compared with the excipient group (P<0.05). TLR modulation could represent a new therapeutic approach in the prevention of seborrheic dermatitis relapses.

Recurrence-based detection of the hyperchaos-chaos transition in an electronic circuit.

Some complex measures based on recurrence plots give evidence about hyperchaos-chaos transitions in coupled nonlinear systems [E. G. Souza et al., "Using recurrences to characterize the hyperchaos-chaos transition," Phys. Rev. E 78, 066206 (2008)]. In this paper, these measures are combined with a significance test based on twin surrogates to identify such a transition in a fourth-order Lorenz-like system, which is able to pass from a hyperchaotic to a chaotic behavior for increasing values of a single parameter. A circuit analog of the mathematical model has been designed and implemented and the robustness of the recurrence-based method on experimental data has been tested. In both the numerical and experimental cases, the combination of the recurrence measures and the significance test allows to clearly identify the hyperchaos-chaos transition.

Effects of mobility in a population of prisoner's dilemma players.

We address the problem of how the survival of cooperation in a social system depends on the motion of the individuals. Specifically, we study a model in which prisoner's dilemma players are allowed to move in a two-dimensional plane. Our results show that cooperation can survive in such a system provided that both the temptation to defect and the velocity at which agents move are not too high. Moreover, we show that when these conditions are fulfilled, the only asymptotic state of the system is that in which all players are cooperators. Our results might have implications for the design of cooperative strategies in motion coordination and other applications including wireless networks.

Recurrence analysis of strange nonchaotic dynamics in driven excitable systems.

Numerous studies have shown that strange nonchaotic attractors (SNAs) can be observed generally in quasiperiodically forced systems. These systems could be one- or high-dimensional maps, continuous-time systems, or experimental models. Recently introduced measures of complexity based on recurrence plots can detect the transitions from quasiperiodic to chaotic motion via SNAs in the previously cited systems. We study here the case of continuous-time systems and experimental models. In particular, we show the performance of the recurrence measures in detecting transitions to SNAs in quasiperiodically forced excitable systems and experimental time series.

A programmable electronic circuit for modelling CO2 laser dynamics.

We introduce a programmable electronic circuit implementing the rich dynamics of CO2 laser models. The design and the implementation of the circuit are accomplished by using a programmable analog device, which permits an experimental characterization of the laser dynamics. The experimental results shown in the paper demonstrate that the circuit exhibits homoclinic chaos typical of CO2 laser with feedback modulation of cavity losses. Moreover, experimental results showing that noise regularizes the dynamical time scales of the system are reported.

[Antibacterial effect of Nd:YAG laser in periodontal pockets decontamination: a in vivo study]. / Effetto antibatterico del laser Nd:YAG nella decontaminazione delle tasche parodontali. Uno studio in vivo.

AIM: Tha aim of this paper is to assess the effects in vivo of the Nd: Yag laser on gingival microflora in patients periodontally at risk. METHODS: An investigation has been carried out on 5 patients suffering from serious periodontal disease, with a sub-gingival check-up a week after the treatment. The selected patients presented either a relapse after the raising of a traditional flap, or showed acute phenomena and were, therefore, treated with a laser with the propedeutic intention of surgery; or they refused traditional surgical therapy or presented systematic pathologies that could not be included in the appropriate protocol. Pockets were chosen that had a probe depth of between 5-8 mm, an optic fibre probe was pushed as far as possible into the probe depth, for about 1 minute per site, 5 times, at 30 second intervals. The samples, taken in order to calculate bacteria colonies, were carried out before using the laser, immediately after and, again, 1 week later. RESULTS: All the sites showed a slight reduction in the quantity of colonies forming immediately after the Nd:Yag laser application, while a week later, only if clinical inflammation appeared to be resolved, the bacteria forming colonies seemed to be reduced. CONCLUSION: From this study it can be concluded that the use of the Nd:Yad laser represents, in mild and average periodontitis, a therapeutic aid to scaling and root planing and, in the same way, in serious periodontitis for traditional surgical therapy.

[Alveolar ridge augmentation by means of onlay grafts harvested from mandibular symphysis]. / Correzione di creste ossee edentule mediante prelievi a onlay dalla sinfisi mentoniera.

AIM: Prosthestic-implant rehabilitation in subjects partially, or totally, endentulous is the method of choice for the considerable advantages involved from an aesthetic as well as functional point of view, besides preventing the physiological reabsorption that is established in the edentulous area. However, it is necessary to have an adequate quantity, as well as quality, of bone in order to support the fixture and the masticating load, conditions that up to now could often prove inferior for various reasons. Such a randomized research programme was proposed, in order to increase the bone volume by means of grafted onlays in the mandibular/chin area, with implant positioning 6 months after the operation, as a valid solution to the prosthestic problems found in the bone deficiency area. METHODS: Twenty patients with partial edentulism in the incisor-canine area were chosen. They showed no signs of periodontal diseases, bruxism or parafunctions. They underwent an autogenesis bone graft with the bone being taken from the mandibular/chin area, with positioning of the implant 6 months after the first operation, thus obtaining an increased bone height of 5 to 7 mm. RESULTS: Check ups were carried out in the 1(st) week after surgery, once a month for the first 3 months and then every 6 months and showed a minimal degree of bone reabsorption and an excellent osteo-integrative process. CONCLUSION: The use of onlay autogenous bone, compared to the other methods for increasing bone volume, is a valid solution for prosthetic-implant rehabilitation in edentulous areas.

A nonlinear circuit architecture for magnetoencephalographic signal analysis.

OBJECTIVES: The objective of this paper was to face the complex spatio-temporal dynamics shown by Magnetoencephalography (MEG) data by applying a nonlinear distributed approach for the Blind Sources Separation. The effort was to characterize and differ-entiate the phases of a yogic respiratory exercise used in the treatment of obsessive compulsive disorders. METHODS: The patient performed a precise respiratory protocol, at one breath per minute for 31 minutes, with 10 minutes resting phase before and after. The two steps of classical Independent Component Approach have been performed by using a Cellular Neural Network with two sets of templates. The choice of the couple of suitable templates has been carried out using genetic algorithm optimization techniques. RESULTS: Performing BSS with a nonlinear distributed approach, the outputs of the CNN have been compared to the ICA ones. In all the protocol phases, the main components founded with CNN have similar trends compared with that ones obtained with ICA. Moreover, using this distributed approach, a spatial location has been associated to each component. CONCLUSIONS: To underline the spatio-temporal and the nonlinearly of the neural process a distributed nonlinear architecture has been proposed. This strategy has been designed in order to overcome the hypothesis of linear combination among the sources signals, that is characteristic of the ICA approach, taking advantage of the spatial information.

Direct measurement of electrostriction in optical fibers.

The electrostriction contribution to the nonlinear refractive index in optical fiber was theoretically calculated and measured. Nonlinearity was induced directly by insertion of the optical fiber into an intense external electric field. With this technique both the Kerr and the electrostrictive contributions to the intensity dependence of the nonlinear refractive index in a step-index fiber were measured. Good agreement between calculated and measured values was observed. These results should confirm and explain the differences observed in measurement of n(2) at different bit rates.

[The onset of syndrome X in old age]. / Insorgenza della sindrome X in età geriatrica.

There is evidence that angina-like chest pain associated with normal coronary angiography (syndrome X) may appear in adult patients. We have reviewed the clinical documentation of all the patient aged 65 or more admitted to our hospital because of recent onset typical or atypical angina, who underwent an exercise tolerance test and coronary angiography. Exclusion criteria were ischaemic or valvular heart disease and significant arterial hypertension. The selection lead to a series of 11 patients (6 females, 5 males) aged 65-72 years (mean 69). The bicycle ergometric test was positive in 7 and negative or not diagnostic in 2 patients each. Thallium-201 scintigraphy (performed in 6 patients) revealed reversible perfusion defects in 4 and was equivocal in 2 patients. At coronary angiography 6 patients showed non obstructive lesions (range: 20-40%) and only 5 had normal findings: 2 of these patients showed gastro-intestinal disease which could be considered as possible trigger of chest pain. Thus only 3 patients fulfilled the criteria for a diagnosis of syndrome X. These were 2 females and 1 male and were followed-up for a minimum of 2 years. All were in good condition, with normal left ventricular function free of major cardiac events, although occasional chest pain was still present. We conclude that syndrome X may appear also in the elderly with the same clinical features already described in younger patients. The overall prognosis is good and symptoms are partially insensitive to standard therapy. The low incidence in the older age may be explained, in our series, also by the restricted criteria adapted to select the study population.