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The release of engineered nanomaterials (ENMs) during manufacturing, use and disposal of nano-enabled products (NEPs) is a potential route of environmental nanopollution. To date, there is limited knowledge on the ecological impact of ENMs incorporated in NEP matrices and how they compare to pristine nanoparticles. Here, we examined the fate and effect of silver nanowires (AgNWs) embedded in a cellulose matrix for the production of printed paper electronics (PPE) (nano)technologies. The fate and impact of fragmented AgNWs-PPE was monitored for 21 days in freshwater mesocosms mimicking a pond ecosystem. The Ag release and AgNWs-PPE behavior in water was further characterized in abiotic batch incubations. Qualitative and quantitative analyses were carried out to estimate the Ag partitioning between the environmental compartments and the aging of AgNWs-PPE as well as bioaccumulation and behavioral responses in biota. In contaminated pond mesocosms, the NEP cellulose/polyvinylidene chloride matrix resulted in rapid settling of the Ag on the sediments and prevented Ag release into the water column. The highest aqueous concentration measured corresponded to less than 0.5% of the total Ag introduced. The AgNWs-PPE fragments accumulated at the water sediment interface, where they were rapidly (bio)degraded and became bioavailable for benthic organisms. Aquatic snails accumulated a significant fraction of the Ag (1.4 ± 0.5%) and displayed enhanced burrowing behavior in comparison to controls. In batch experiments, alteration of the ENM morphology was evident at the NEP surface. Here, the colocalization of Ag and S clusters suggests aging viasulfidation, similar to other pristine Ag ENMs. However, the cellulose matrix prevented weathering of the AgNWs within the NEP, which presented a near-pristine state even after 21 days of incubation. Overall, these results indicate that the fate and impact of Ag embedded in the AgNWs-PPE were driven by the cellulose matrix. In particular, given the specific properties and behavior of paper-based (nano)products, these may constitute a unique category when evaluating NEP environmental impact. The data gathered in this study can help in defining the environmental fate of such materials and provide useful information to address future studies focused on ENM environmental fate and risk assessment in a life-cycle perspective.

In the past decade, mesocosms have emerged as a useful tool for the environmental study of engineered nanomaterials (ENMs) as they can mimic the relevant exposure scenario of contamination. Herein, we analyzed the scientific outcomes of aquatic mesocosm experiments, with regard to their designs, the ENMs tested, and the end points investigated. Several mesocosm designs were consistently applied in the past decade to virtually mimic various contamination scenarios with regard to ecosystem setting as well as ENMs class, dose, and dosing. Statistical analyses were carried out with the literature data to identify the main parameters driving ENM distribution in the mesocosms and the potential risk posed to benthic and planktonic communities as well as global ecosystem responses. These analyses showed that at the end of the exposure, mesocosm size (water volume), experiment duration, and location indoor/outdoor had major roles in defining the ENMs/metal partitioning. Moreover, a higher exposure of the benthic communities is often observed but did not necessarily translate to a higher risk due to the lower hazard posed by transformed ENMs in the sediments (e.g., aggregated, sulfidized). However, planktonic organisms were generally exposed to lower concentrations of potentially more reactive and toxic ENM species. Hence, mesocosms can be complementary tools to existing standard operational procedures for regulatory purposes and environmental fate and risk assessment of ENMs. To date, the research was markedly unbalanced toward the investigation of metal-based ENMs compared to metalloid- and carbon-based ENMs but also nanoenabled products. Future studies are expected to fill this gap, with special regard to high production volume and potentially hazardous ENMs. Finally, to take full advantage of mesocosms, future studies must be carefully planned to incorporate interdisciplinary approaches and ensure that the large data sets produced are fully exploited.

Most works on mechanism synthesis consider models that employ trigonometric functions and rely on derivative-free optimisation, such as bio-inspired and hybrid heuristics. Derivative-free strategies have the advantage of being applied directly to explore the design space. However, such strategies require tuning to achieve satisfactory results and do not provide certificates of solution quality. To this end, this work presents two alternative models: the first one consists of a trigonometric function-based model; while the second relies solely on natural coordinates, in which the nonlinear terms are bilinear. Both models result in mixed-integer nonlinear programming (MINLP) formulations. Mechanism constraints are conveniently expressed in this formulation, including Grashof's condition, prescribed timing, and increasing and decreasing angle sequence. In standard numerical cases of four-bar linkage path synthesis, global and local MINLP solvers yielded provably optimal designs in some cases and in others they outperformed works from the literature.

The study of mechanisms is one of the most important areas on which machine design relies. Research in mechanism can be roughly divided into two main problems: mechanism analysis and mechanism synthesis. This paper focuses on topology analysis of mechanism, by means of screw theory representation of mechanisms. Freedoms and constraints in mechanisms are thus described applying the Kirchhoff's laws adaptation to multibody systems proposed by Davies. Based on this modelling, overconstraint in mechanisms is analysed in terms of free motions and constraints. The self-aligning mechanisms kinematically equivalent to an overconstraint mechanism are investigated. Two new algorithms for enumerating all self-aligning kinematically equivalent mechanisms to an overconstrained one and for selecting an optimal self-aligning topology, based on a set of criteria, are proposed. All algorithms have been implemented in Sage software and run in polynomial time. Examples of applications are presented, and the results obtained are validated with literature cases.

Objective.We present an overview of international literature concerning macroglossia-related etiology, clinical and instrumental diagnoses, surgical treatments, complications, and recurrences. Moreover, we present a series of cases of patients affected by macroglossia who have been treated surgically at the Department of Maxillofacial Surgery of the University of Rome “La Sapienza”. Methods.Between 1990 and 1999, only after attempts to solve this pathologic condition with medical and orthodontic treatment, we treated surgically a total of 7 patients (4 male and 3 female). The surgical techniques used were Köle glossectomy and Dingman and Grabb glossectomy. We analyzed the clinical and instrumental study and the surgical treatment, including possible complications and recurrences. Results.After follow-up of a period from 2 to 9 years, macroglossia recurrences were absent, showing that the Köle and the Dingman and Grabb glossectomies are viable surgical options for treatment of macroglossia. Conclusion.The best therapy for each case macroglossia must be carefully evaluated, with the right medical therapy and orthodontic therapy attempted first and surgical treatment performed only when the first and second therapy fail. Moreover, surgical techniques must be chosen in accordance with the functional results that one wants to achieve and must be the most conservative technique to preserve the vascular-nerve bundle. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002;94:566-71)

The authors assessed the rate of craniomaxillofacial fractures in soccer and the areas where they occur, describing above all the injury pattern of this sport. Over a 5-year period (1995–2000) 46 cases of 329 with fractures associated with different sports activities have been surgically operated at the maxillofacial surgery department of the Policlinico “Umberto I” Hospital, University “La Sapienza” of Rome.

Osteoma is a benign, slow-growing tumor, which mainly occurs in the bones and cavities of the middle third of the face, representing the most frequent benign tumor of the paranasal sinuses. Osteoma of the paranasal sinuses is generally asymptomatic and it is discovered only as a coincidental radiological finding; when it becomes symptomatic, the most common presenting symptoms are headaches and facial pain. Rarely the sinusal osteoma may entail secondary orbital extension, with ocular signs and symptoms. Primary intraorbital involvement is extremely rare. The authors present a review of the literature and report two cases of primary orbital osteoma. In both cases surgical treatment led to the complete remission of symptoms. Diagnosis and surgical therapy are discussed.

DNA from female and male hemp (Cannabis sativaL.) plants belonging to nine different varieties were screened with180 RAPD primers in a search for sex-associated DNA markers. About 1500bands were produced in total, nine primers were found yielding one or two DNA bands amplified in all nine male DNA bulks and absent in all female DNA bulks. These putatively male-associated markers were then scored in three different F1progenies, deriving from a cross between a common male parent and three different female plants. The sex of the progeny was accurately scored on the basis of the floral phenotype, and the presence of the nine male-associated markers was verified by RAPD analysis. In all three progenies examined, all the male plants showed the DNA markers previously identified by bulk segregant analysis (BSA) on the hemp varieties, while all the female plants lacked them. The fact that the association between these markers and the staminate phenotype is found when examining male plants of distantly related varieties, and that such linkage is never broken when different progenies are examined, strongly supports the hypothesis that the markers found are physically located on the Y chromosome, in a region excluded from recombination during meiosis. Another marker was shown to be present in the male parent, in all the male plants of each progeny, and in 50% of the female progenies, while it was absent in the female parent; the possible occurrence of markers deriving from multiple amplification sites of the genome is discussed.

Sensory impairment after bilateral sagittal split osteotomy (BSSO) due to inferior alveolar nerve (IAN) lesions may be either temporary or permanent and either complete or partial. The aim of this prospective study is to evaluate, by means of objective sensory testing, IAN sensory disturbances development in patients who underwent BSSO.

Seventy-seven cases of delayed or inadequately treated zygoma fractures, treated between 1977 and 1999 in the Maxillofacial Surgery Division of the La Sapienza University in Rome, are presented. The functional and aesthetic problems caused by this pathology are analyzed. The results achieved resolve some of the various aspects of inadequately treated malar fractures. These are possible because of the development of great biomaterials and the introduction of rigid internal fixation. As a consequence the surgical techniques have been revolutionized. Cases, with functional-aesthetic deficits or only aesthetic deficits, are studied separately. An accurate preoperative study permits the operation suitable for the specific features of the individual case to be carried out.

Pleomorphic adenoma affecting the lachrymal gland requires a well-grounded clinical and therapeutic protocol to avoid the risk of malignant transformation or disease recurrence, which is quite dangerous at this site. The authors present a clinical case of pleomorphic adenoma recurrence affecting the right lachrymal gland in a patient who first underwent a biopsy, with subsequent resection of the neoplasm. The authors also review the clinical and radiological features enabling a differential diagnosis and describe the radical “exenteratio orbitae” surgery for pleomorphic adenoma recurrence 7 years after the first operation, which was performed because of total derangement of the orbital cavity. The patient remains disease-free 5 years after this surgical treatment. Therefore, it turns out that an incisional biopsy carries a higher biological cost for the patient.

The objective was to study the genetic structure and degree of variability of hemp (Cannabis sativaL.) varieties. Six varieties of hemp were analyzed by random amplified polymorphic DNA (RAPD) analysis, using 10 plants per variety. The varieties were a dioecious landrace, a dioecious selection from it, a cross‐bred cultivar, a monoecious variety, a drug strain, and an inbred female line. The genetic complexity of each cultivar was investigated by determining the number of bands produced by the primers used, the number of fixed and polymorphic loci, the average allele frequency, and the heterozygosity. A good correlation was found between these parameters and the genetic origin and breeding strategy of each variety. The average polymorphism over all varieties and loci was 97.1%; the single cultivar polymorphism ranged from 31.1 to 85.5%. Heterozygosity ranged from 0.05 (inbred female line) to 0.26 (cross‐bred Fibranova). The average heterozygosity calculated over all 102 loci and all plants studied was 0.29. The Fst (Wright's fixation index) value calculated for all loci was 0.48, and only 33.3% of the scored loci had higher values and can be considered informative for cultivar identification. A Fisher's test based on allele frequencies suggested complete differentiation among all varieties, with the exception of the Italian dioecious varieties Carmagnola and CS, for which no discriminating alleles were found. The correlations among the molecular data and the genetic structure of the different cultivars and the consequences in relation to variety discrimination in hemp are discussed.

The authors present the clinical case of a 61-year-old patient with Hand-Schüller-Christian disease associated with multisystemic involvement. The onset of such puzzling symptoms and the extremely rarity of this disease in a patient of such advanced age resulted in a delayed diagnosis and subsequently delayed treatment of the patient.

The CMS central DAQ system is built using commercial hardware (PCs and networking equipment), except for two components: the Front-end Readout Link (FRL) and the Fast Merger Module (FMM). The FRL interfaces the sub-detector specific front-end electronics to the central DAQ system in a uniform way. The FRL is a compact-PCI module with an additional PCI 64bit connector to host a Network Interface Card (NIC). On the sub-detector side, the data are written to the link using a FIFO-like protocol (SLINK64). The link uses the Low Voltage Differential Signal (LVDS) technology to transfer data with a throughput of up to 400 MBytes/s. The FMM modules collect status signals from the front-end electronics of the sub-detectors, merge and monitor them and provide the resulting signals with low latency to the first level trigger electronics. In particular, the throttling signals allow the trigger to avoid buffer overflows and data corruption in the front-end electronics when the data produced in the front-end exceeds the capacity of the DAQ system. Both cards are compact-PCI cards with a 6U form factor. They are implemented with FPGAs. The main FPGA implements the processing logic of the card and the interfaces to the variety of busses on the card. Another FPGA contains a custom compact-PCI interface for configuration, control and monitoring. The chosen technology provides flexibility to implement new features if required. [Copyright &y& Elsevier]