Experimental and theoretical investigation of 2D nanoplatelet-based conversion layers for color LED microdisplays.

In the field of augmented reality, there is a need for very bright color microdisplays to meet the user specifications. Today, one of the most promising technology to manufacture such displays involves a blue micro-LED technology and quantum dots-based color conversion layers. Despite recent progress, the external power conversion efficiencies (EPCE) of these layers remain under ∼25%, below the needs (>40%) to reach a white luminance of 100,000 cd/m2. In this work, we have synthesized CdSexS1-x nanoplatelet-based conversion layers for red and green conversion, and measured their absorption properties and EPCE performances with respect to layer thickness. On this basis, a model was developed that reliably predicts the layer EPCE while using only few input data, namely the layer absorption coefficients and the photoluminescence quantum yield (PLQY) of color photoresist. It brings a new insight into the conversion process at play at a micro-LED level and provides a simple method for extensive optimization of conversion materials. Finally, this study highlights the outstanding red conversion efficiency of photoresist layers made of core-double shell CdSexS1-x nanoplatelets with 31% EPCE (45% external PLQY) for 8 µm-thick conversion layer.

Presence of Legionella spp. in human dental plaque.

AIMS: The aim of this research is to verify the presence of Legionella in human dental plaque. METHODS: 65 adult patients not treated with systemic or local antibiotics at least 2 months before the time of sample collection were enrolled for plaque collection between September 2015 and December 2016. A brief questionnaire about lifestyle and health risks was administered. Legionella spp. detection has been executed by semi- nested PCR. RESULTS: 8 out of 65 plaque samples (12.3%) were positive for Legionella spp. As regards health risks and lifestyle aspects, no relevant difference was observed between patients involved in our study, except for two positive patients who have reported a COPD ongoing and a pneumonia in the past. CONCLUSIONS: This study represents a step forward in the knowledge of reservoirs of the microorganism and richness of oral microbiota.

Group 1 CD1-restricted T cells and the pathophysiological implications of self-lipid antigen recognition.

T cell responses are generally regarded as specific for protein-derived peptide antigens. This is based on the molecular paradigm dictated by the T cell receptor (TCR) recognition of peptide-major histocompatibility complexs, which provides the molecular bases of the specificity and restriction of the T cell responses. An increasing number of findings in the last 20 years have challenged this paradigm, by showing the existence of T cells specific for lipid antigens presented by CD1 molecules. CD1-restricted T cells have been proven to be frequent components of the immune system and to recognize exogenous lipids, derived from pathogenic bacteria, as well as cell-endogenous self-lipids. This represents a young and exciting area of research in immunology with intriguing biological bases and a potential direct impact on human health.

Cognitive, behavioral, and psychological phenotypes in small fiber neuropathy: A case-control study.

OBJECTIVE: Small fiber neuropathy (SFN) is a well-defined chronic painful condition causing severe individual and societal burden. While mood disorders have been described, cognitive and behavioral profiles of SFN patients has not been investigated. METHODS: Thirty-four painful SFN patients underwent comprehensive cognitive, behavioral, psychological, quality of life (QoL), and personality assessment using validated questionnaires. As control samples, we enrolled 36 patients with painful peripheral neuropathy (PPN) of mixed etiology and 30 healthy controls (HC). Clinical measures of neuropathic pain, duration, frequency, and intensity of pain at the time of assessment were recorded. Between-group and correlation analyses were performed and corrected for multiple comparisons. RESULTS: No differences in clinical measures were found between SFN and PPN, and all groups had similar cognitive profiles. SFN patients showed higher levels of anxiety and alexithymia (p < .005) compared to PPN and HC, considering also pain intensity. Maladaptive coping strategies characterized both patient groups, but only SFN revealed higher levels of acceptance of pain (p < .05). Pain intensity and neuropathic symptoms were associated with mood, low QoL and catastrophism (p < .001), particularly, the higher the perceived pain intensity, the higher the use of maladaptive coping strategies (p < .001). The personality assessment revealed significant feelings of worthlessness and somatization traits both in SFN and PPN (p < .002 vs HC). DISCUSSIONS: our results suggest that SFN patients had a normal-like cognitive profile, while their behavioral profile is characterized by mood disorders, alexithymia, maladaptive coping strategies, and poor QoL, as other chronic pain conditions, possibly related to pain intensity. Personality assessment suggests that somatization and feelings of worthlessness, which may worsen the neuropsychological profile, deserve clinical attention when considering patients' therapeutic approaches. At the same time, the high level of acceptance of pain is promising for therapeutic approaches based on psychological support.

Environmental risk factors for amyotrophic lateral sclerosis: methodological issues in epidemiologic studies.

The exact role of environmental risk factors in the etiology of the neurodegenerative disease amyotrophic lateral sclerosis (ALS) is still unknown. Their hypothetical contribution ranges from a minimal impact to a major role. Among the environmental factors strictu sensu (i.e., not life-style factors) suspected to play a role in ALS etiology, we consider pesticides, the metalloid selenium, some heavy metals, magnetic fields and cyanobacteria. However, the possibility exists that these factors exert their activity only in genetically susceptible persons and only after long-term exposures, thus further hampering epidemiologic studies. The recent availability of powerful tools such as population-based ALS registries for case ascertainment and clustering detection, and of environmental modeling techniques and of geographical information systems, may yield unique opportunities for offering insight into the etiology of the disease.

Dental unit water content and antibiotic resistance of Pseudomonas aeruginosa and Pseudomonas species: a case study.

Background: Many studies consider the contamination of dental unit waterlines (DUWLs), but few of them have studied the possible presence of antibiotic resistant Pseudomonas aeruginosa in the DUWLs. Aims: Investigation of the presence of P. aeruginosa and Pseudomonas spp. strains in DUWLs and evaluation of their resistance to six antibiotics (ceftazidime, netilmicin, piperacillin/tazobactam, meropenem, levofloxacin, colistin sulfate) at a public dental clinic in Milan, Italy. Results: Dental units were contaminated by P. aeruginosa with loads of 2-1,000 CFU/L and were mainly located on the mezzanine floor, with a range of 46-54%, while Pseudomonas spp. were primarily found on the first and second floors, ranging from 50 to 91%. P. aeruginosa was antibiotic resistant in 30% of the strains tested, andPseudomonas spp. in 31.8% . Cold water from controls was also contaminated by these microorganisms. Conclusion: Monitoring antibiotic resistance in the water and adopting disinfection procedures on DUs are suggested within the Water Safety Plan.

[Hygienic profile of the water in Milan swimming pools: a three-year comparative study]. / Profilo igienico-sanitario dell'acqua delle piscine milanesi: tre anni a confronto.

The aim of this work was to determine whether swimming pool water quality in Milan from 2006 to 2008 was within the standards established by national and local Italian laws (Circolare Min. Sanità 128/71 and DGR 2552/2006). In 2006, 580 samples of water from public swimming pools were analyzed to determine the presence of heterotrophic counts at 37 degrees and total coliforms; pH, free chlorine and chloride of each sample were also measured. In the following years, water from both public and private swimming pools were examined to measure heterotrophic count at 22 degrees and 36 degrees, Escherichia coli, enterococci, Pseudomonas aeruginosa, Staphylococcus aureus, pH, free chlorine, and nitrates. The total number of analyses carried out in 2007 and 2008 was 2074 and 1532, respectively. In 2006, the extent of noncompliance of all swimming pools that was observed for both physical/chemical and microbiological parameters was 72.3%, which then decreased to 53.2% and 36.2% in 2007 and 2008, respectively. In particular with regard to the microbiological analysis, an increase of noncompliance based on at least one parameter was determined (7.1% in 2006 vs. 21.5% in 2007 and 22% in 2008). In contrast, a decrease of the extent of noncompliance based on at least one physical/chemical parameter was observed (from 68.1% in 2006 to 40.4% and 22.3% in 2007 and 2008, respectively). Interestingly, public swimming pools exceeded the legal limits of microbiological concentration more often than the private ones, whereas both types of swimming pools showed a decrease in noncompliance with regard to the physical/chemical parameters.

[Investigation on strains of Legionella pneumophila, isolated from a hospital of Milano, with three genotyping methods]. / Genotipizzazione di ceppi di Legionella pneumophila, isolati in strutture sanitarie di differenti tipologie.

Various techniques have been developed in recent years for the molecular typing of microorganisms. Remains particularly difficult to isolate clinical strains for the low availability of cases and even more problematic matching clinical / environmental strains. We investigated 13 strains of Legionella pneumophila of clinical and environmental origin, isolated in 3 Health Facilities in Milan (2003-2006), using three molecular typing methods: Pulse-Field Gel Electrophoresis, Amplified Fragment Length Polymorphism and Sequence-Based Typing. PFGE and AFLP showed the correlation between a clinical case with only one of the environmental isolates taken from the places frequented by the patient, demonstrating with certainty the nosocomial origin of the case and identifying the source of infection in the shower water (Clin. 1 and Env. 1N). Two clinical samples from patients admitted to different wards presented an identical profile, which suggests that the nosocomial origin assumed an epidemic form, even without having isolated the environmental strain due to the absence of samples drawn during the period under consideration (Clin. 2 and 3). Finally, the comparison between the isolated environmental strains demonstrated a heterogeneous presence of strains, not correlated to each other although they belong to the same serum-group, having profiles that are clearly different regarding number and position of bands (Env. 2 and 4). The profile 2,10,18,10,1,1 had never been isolated and typed previously in Europe. The SBT has proved a better technique for reproducibility and interpretation of results than PFGE and AFLP To complete studies on SBT method, now considered gold standard, is currently being the EWGLI 5th Proficiency Panel, in which we are actively involved with the genotyping of five strains according to the latest version of the protocol (4.1).

[5-year surveillance for Legionella pneumophila and comparison of disinfection methods in two hospitals of Milan]. / Sorveglianza ambientale di Legionella pneumophila e meto- di di bonifica a confronto in strutture sanitarie di Milano (risultati di un quinquennio).

We performed an environmental monitoring in an hospital to estimate the level of contamination from Legionella spp., in connection with several treatments of reclamation. In period 2002-2006 we executed 238 samplings in 21 units hospitals (from hot water, biofilm, filter of the conditioning system, instrument for the assisted respiration) for the detection of Legionella spp. The contaminated points have been subordinates to reclamation (hyperchlorination, maintenance of boilers/tanks, taps' and showers' substitution, increased temperature, elimination of dead points of the system and chlorine dioxide) and subsequently we sampled to verify the efficiency of the disinfection. Environmental investigation found 58% of the cases positive for Legionella spp. (139/238), with maximum count in order of the 10(4) UFC/L, demonstrating colonization of Legionella pneumophila (132/139, 70% Serogroup 2-14, 19% Serogroup 1, 11% both). The used treatments were effective, in different ways, in the short period, but not in the medium-term, because progressive recolonization happened approximately after a month; only the use of chlorine dioxide brought to counts less than 100 UFC/L until now. Chlorine dioxide seems to maintain a mainly protecting effect, however this effectiveness will have to be demonstrated also for longer periods.

Evaluation of Milan University Dental Students' knowledge of health and hygiene risks related to clinical work.

AIM: Several different subjects in the Degree Course in Dentistry and Prosthodontics, including Hygiene, are of fundamental importance to understand and prevent hygiene/ health risks in the dental field. The aim of this investigation is to evaluate the knowledge acquired by students during the Degree Course in Dentistry. METHODS: A questionnaire was distributed to 121 students of the Degree Course in Dentistry and Prosthodontics at Milan University; the questionnaire, drawn up by the Working Group SItI ''Hygiene in Dentistry'' was structured in 3 parts: personal data; transmission of infectious diseases in dentistry; measures to control and prevent cross-infection. RESULTS: The students were all aware of the health/hygiene risks in dentistry; they knew the principal transmissible infectious diseases (while confusing actual risk of transmission with disease's fears) and the procedures at highest risk of cross-infection for patients and dental professionals; they correctly determined the highest-risk categories of patients and the individual protection devices to be used in dental practice. However, they knew little about their own vaccination status; a low percentage of students answered correctly on which environmental matrices can be contaminated or the more technical questions on disinfection and sterilisation procedures for the instruments employed. CONCLUSIONS: The students' replies show they possess a fair theoretical knowledge of transmission risks; however, some gaps exist above all in the practical application of this knowledge, and it appears clear that these should be addressed in detail, possibly with the help of a specific tutor providing support during normal clinical work in the last year of the course.

[Hygiene-sanitary risks associated with dentistry in the city of Milan. Questionnaire-based survey]. / Rischi igienico-sanitari legati all'assistenza odontoiatrica, nella città di Milano. Indagine questionaria.

BACKGROUND: Aim of this investigation is to identify possible sanitary risks connected with the practice of dentistry and to draw up guidelines which may help all those who work in this field. METHODS: Between April and July 1998, we distributed 231 questionnaires to public and private dental offices in Milan, to evaluate dentists' knowledge of sanitary risks in their practices. One hundred and sixteen of the 231 distributed questionnaires were returned. All the dentists contacted, used protective measures such as gloves, masks, glasses, and high-speed aspirators. RESULTS: Survey responses indicated that the most readily transmittable infectious diseases in dentist's practices are, in order of importance, hepatitis, AIDS, airborne diseases, and herpes. Surgery, endodontics, and the use of sharp instruments most likely lead to transmission of pathogens in both patients and dentists. Dentist's knowledge of out-patient treatment is good whereas their knowledge of the use of disinfectants for dental equipment is poor. CONCLUSIONS: The latter suggests the utility of continuing education in this critical aspect of the practice of dentistry.

[Dental offices and environment quality]. / Ambulatorio odontoiatrico e qualità ambientale.

AIM: The aim of this study was to survey, from a microbiological point of view, dental unit water, air and surface quality in public dental offices and in control environments in Milan. METHODS: We studied tap and dental unit water (from fountain, air-water syringe, turbine), at the beginning and at the end of monday and thursday morning activity; air quality with surface air system (SAS) in dental and control offices; handpieces holder, fountain block, arm of the light, dental trolley, inner and outer walls surfaces quality. RESULTS: Water from the dental unit waterline shows average exceeding the law limits 2-3 fold for total bacteriological counts at 37 degrees and 22 degrees, in all examined points, at the beginning of the working day. There is an improvement in the water contamination at the end of the activity. Pseudomonas aeruginosa is frequently found, total and fecal coliforms are absent, while Legionella pneumophila was found only in one control. Air and surfaces quality is quite good, especially in places with ventilation systems in function. CONCLUSION: Dental unit water is the most critical point among those monitored. Water quality has to be improved with specific projects.

[Quality of some working places in Milan]. / Indagine conoscitiva della qualità di ambienti di lavoro nella città di Milano.

Questionnaires were distributed to the responsibles and to the dependents of structures with high turnover of people, to have informations about numbers and typology of instruments, habits of dependents and type of cleanings. In these structures, microbiologic quality of air and of informatic instruments' surfaces were evaluated and efficacy of treatment with some products of cleaning and sanification was verified. Air microbiological contamination was comparable to that found in other similar researchs. Fecal contamination indicators were not found on instruments' surfaces, both before, and after treatment; in 8 cases (3%) Staphylococcus aureus was isolated and in 6 cases (2%) species of not pathogenous staphylococci were isolated. At the beginning of the working day, mean values of total aerobic bacterial count at 22 degrees and 37 degrees, were low, settled to zero after treatment and increased progressively during the week. Infective risk for workers can be considered insignificant because of low microbiological contamination. Specific sanification products seem not to be necessary, since common products of cleaning have the same efficacy.