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O propósito deste trabalho é pesquisar a influência do tempo de ensaio (t) e da concentração de lama abrasiva (C) sob o comportamento ao desgaste microabrasivo de uma liga de aço contendo aluminetos de ferro. Ensaios “ball-cratering” foram conduzidos sob a liga fabricada Fe-30Al-6Cr (at.%), junto a uma esfera de aço AISI 52100 e lamas abrasivas preparadas com óxido de alumínio (Al2O3) + água. Diferentes condições de ensaio foram estabelecidas e os resultados mostraram que o tempo de ensaio e a concentração da lama abrasiva influenciaram as atuações dos modos de desgaste microabrasivo e o volume de desgaste (V), sendo V proporcional à t e C (V (t,C)).

This paper presents a combined subjective and objective evaluation of an application mixing interactive virtual reality (VR) experience with 360° storytelling. The hypothesis that the modern immersive archaeological VR application presenting cultural heritage from a submerged site would sustain high levels of presence, immersion, and general engagement was leveraged in the investigation of the user experience with both the subjective (questionnaires) and the objective (neurophysiological recording of the brain signals using electroencephalography (EEG)) evaluation methods. Participants rated the VR experience positively in the questionnaire scales for presence, immersion, and subjective judgement. High positive rating concerned also the psychological states linked to the experience (engagement, emotions, and the state of flow), and the experience was mostly free from difficulties linked to the accustomization to the VR technology (technology adoption to the head-mounted display and controllers, VR sickness). EEG results are in line with past studies examining brain responses to virtual experiences, while new results in the beta band suggest that EEG is a viable tool for future studies of presence and immersion in VR.

The comprehensive characterization of Intramolecular Charge Transfer (ICT) stemming in push-pull molecules with a delocalized π-system of electrons is noteworthy for a bespoke design of organic materials, spanning widespread applications from photovoltaics to nanomedicine imaging devices. Photo-induced ICT is characterized by structural reorganizations, which allows the molecule to adapt to the new electronic density distribution. Herein, we discuss recent photophysical advances combined with recent progresses in the computational chemistry of photoactive molecular ensembles. We focus the discussion on femtosecond Transient Absorption Spectroscopy (TAS) enabling us to follow the transition from a Locally Excited (LE) state to the ICT and to understand how the environment polarity influences radiative and non-radiative decay mechanisms. In many cases, the charge transfer transition is accompanied by structural rearrangements, such as the twisting or molecule planarization. The possibility of an accurate prediction of the charge-transfer occurring in complex molecules and molecular materials represents an enormous advantage in guiding new molecular and materials design. We briefly report on recent advances in ultrafast multidimensional spectroscopy, in particular, Two-Dimensional Electronic Spectroscopy (2DES), in unraveling the ICT nature of push-pull molecular systems. A theoretical description at the atomistic level of photo-induced molecular transitions can predict with reasonable accuracy the properties of photoactive molecules. In this framework, the review includes a discussion on the advances from simulation and modeling, which have provided, over the years, significant information on photoexcitation, emission, charge-transport, and decay pathways. Density Functional Theory (DFT) coupled with the Time-Dependent (TD) framework can describe electronic properties and dynamics for a limited system size. More recently, Machine Learning (ML) or deep learning approaches, as well as free-energy simulations containing excited state potentials, can speed up the calculations with transferable accuracy to more complex molecules with extended system size. A perspective on combining ultrafast spectroscopy with molecular simulations is foreseen for optimizing the design of photoactive compounds with tunable properties.

Within the i-MareCulture and Lab4Dive projects, an international partnership is developing different technologies for both in-situ and virtual underwater exploration. In particular, an underwater tablet dedicated to the archaeological sites is being developed to improve the recreational diving experience and support the research activities conducted by the archaeological divers. This tablet allows the diver to recognize his position in the underwater site, to acquire geo-localized photos and notes and to visualize the hypothetical reconstruction of the underwater remains through the augmented reality. In addition, it has been realized a virtual diving application that enables every user to explore some different underwater archaeological sites of the Mediterranean Sea without the need to conduct a proper dive. This virtual visit can be enjoyed by means of different Head Mounted Displays (HMDs), such as the HTC Vive, the Samsung Gear VR or the Google Daydream, exploiting the features of these devices to interact with the virtual environment. During the visit, additional information can be obtained playing some videos realized with the typical approach of the storytelling and a 360° field of view.

Background: Self-directed multimedia resources that provide psycho-educational information to selected populations have been supported in child health related areas including parenting skills in adults and literacy in children. Comparable programs for use with bereaved children and families have not been adequately developed or empirically examined. Examining usability and satisfaction with such materials is critical, especially when dealing with bereavement. Objective: This study evaluated the feasibility of the multimedia kit "Talk, Listen, Connect III: 'When Families Grieve™'" ("TLC III") for use with caregivers and their parentally bereaved children (ages 2-16 years). Primary outcomes included the utilization and overall satisfaction with the "TLC III" kit and the kit's impact on caregiver-child communication. Secondary outcomes, engagement, family coping, and caregiver and child grief also were examined. Participants: Ninety-three caregivers completed pre- and post-viewing questionnaires (59 in the "TLC III" group, 34 in the comparison group). Results: Caregivers who viewed the "TLC III" kit materials reported greater satisfaction with kit materials and greater impact on family coping with death than did caregivers who viewed the "Ready" kit. No significant differences were found with regard to pre- to post-test changes on any of the primary or secondary outcome measures after controlling for pretest scores. Conclusions: Multimedia programs should be considered as adjuncts or alternatives to traditional therapies and further evaluated for use with parental bereavement; particularly among inaccessible segments of the population. Future studies should consider innovative approaches to examining the effects of such programs on complex problems faced by children.

A tomada de decisão financeira é um dos aspectos estudados pelas Finanças Comportamentais, que partem do pressuposto da racionalidade limitada dos indivíduos. Considerando especificamente os estudantes, pode-se compreender a validade dos julgamentos realizados, sendo um auxílio na atuação profissional dos mesmos. Assim, o presente estudo buscou analisar os vieses comportamentais de aversão à perda e excesso de confiança nos estudantes do Curso de Administração de uma Universidade do Rio Grande do Sul sob a ótica do gênero. O primeiro viés faz com que os indivíduos corram riscos mais freqüentes em suas decisões, já o segundo, faz com que os mesmos confiem mais do que deveriam em seus próprios conhecimentos e opiniões. Realizou-se uma pesquisa survey composta por 81 respondentes, a partir de um questionário estruturado, o qual abordou os vieses comportamentais e questões de perfil. Por meio da análise foi possível observar que os estudantes possuem os vieses analisados e que estes afetam a tomada de decisão. Sob a ótica do gênero, percebeu-se que não há diferença.

Background and study aims Endoscopic drainage of walled-off pancreatic necrosis (WOPN) is feasible when contact with the gastric or duodenal wall is present; when WOPN cannot be accessed endoscopically, a percutaneous approach can be considered. Percutaneous use of esophageal self-expandable metal stents (SEMS) to establish access to a WOPN cavity was evaluated.

CK2 is a pleiotropic S/T protein kinase (formerly known as casein kinase 2) which is attracting increasing interest as therapeutic target, and the identification of its substrates is a crucial step in determining its involvement in different pathological conditions. We recently found that S131 of Akt2 (homologous to the well established CK2 target S129 of Akt1) is not phosphorylated by CK2 either in vitro or in vivo, although the consensus sequence recognized by CK2 (S/T-x-x-E/D/pS/pT) is conserved in it. Here, by exploiting synthetic peptides, in cell transfection experiments, and computational analysis, we show that a single sequence element, a T at position n+1, hampers phosphorylation, causing an α-helix structure organization which prevents the recognition of its own consensus by CK2. Our results highlight the role of negative determinants as crucial modulators of CK2 targeting and corroborate the concept that Akt1 and Akt2 display isoform specific features. Experiments with synthetic peptides suggest that Akt2 S131 could be phosphorylated by kinases of the Plk (Polo-like kinase) family, which are insensitive to the presence of the n+1 T. The low phylogenetic conservation of the Akt2 sequence around S131, as opposed to the extremely well-conserved Akt1 homologous sequence, would indicate a dominant positive role in the selective pressure only for the Akt1 phosphoacceptor site committed to undergo phosphorylation by CK2. By contrast, Akt2 S131 may mediate the response to specific physio/pathological conditions, being consequently shielded against basal CK2 targeting.

Dystroglycan (DG) is a membrane receptor, belonging to the dystrophin-glycoprotein complex (DGC) and formed by two subunits, α-dystroglycan (α-DG) and β-dystroglycan (β -DG). The C-terminal domain of α-DG and the N-terminal extracellular domain of β -DG are connected, providing a link between the extracellular matrix and the cytosol. Under pathological conditions, such as cancer and muscular dystrophies, DG may be the target of metalloproteinases MMP-2 and MMP-9, contributing to disease progression. Previously, we reported that the C-terminal domain α-DG (483-628) domain is particularly susceptible to the catalytic activity of MMP-2; here we show that the α-DG 621-628 region is required to carry out its complete digestion, suggesting that this portion may represent a MMP-2 anchoring site. Following this observation, we synthesized an α-DG based-peptide, spanning the (613-651) C-terminal region. The analysis of the kinetic and thermodynamic parameters of the whole and the isolated catalytic domain of MMP-2 (cdMMP-2) has shown its inhibitory properties, indicating the presence of (at least) two binding sites for the peptide, both located within the catalytic domain, only one of the two being topologically distinct from the catalytic active groove. However, the different behavior between whole MMP-2 and cdMMP-2 envisages the occurrence of an additional binding site for the peptide on the hemopexin-like domain of MMP-2. Interestingly, mass spectrometry analysis has shown that α-DG (613-651) peptide is cleavable even though it is a very poor substrate of MMP-2, a feature that renders this molecule a promising template for developing a selective MMP-2 inhibitor.

Introduction: Marfan’s Syndrome (MS) is a multisystem disorder of the connective tissue. A number of oral manifestations and craniofacial characteristics show a strong correlation with MS. There are no data available in the literature with regard to morphological characteristics of the maxilla in Marfan’s syndrome assessed by 3D morphometric analysis. Aim: To use geometric morphometric analysis in order to evaluate the characteristics of palatal shape in a group of Marfan subjects compared with a control group. Materials and Methods: For this preliminary study, a group of five male subjects (mean age of 9.1±0.8 years) with a clinical diagnosis of MS were selected for the Marfan Group (MG). The Control Group (CG) was composed of five non-syndromic male subjects (mean age 9.3±0.6) years. Maxillary study casts of all subjects were scanned using an extraoral scanner. Landmarks and semi landmarks were digitized (239 landmarks) and geometric morphometric methods were used. Procrustes analysis was applied and principal component analysis was performed to reveal the main patterns of palatal shape variation. Results: A statistically significant difference between the palate’s shape of MG and CG was found. The variability described by the first principal component was morphologically the most significant because it defines the 65.7% of total shape variability and describes changes in all three dimensions. MG mainly presents alteration of the palatal vault in the vertical plane and in the transverse dimension of the posterior region. Conclusion: Marfan subjects have a specific palatal morphology characterised by high palatal vault and narrow maxillary posterior region.

Ever since the Middle Ages, the relation between nature and architecture has characterised Mantua’s environmental situation and urban form. The artificial formation of the lakes transformed the city into a peninsula and placed it in the state of a comprehensive artefact whose complexity had to be considered in the case of every new intervention. Water is the limen of the city’s essence: the boundary separating it from the countryside and a defensive barrier; a threshold between nature and artifice by means of embankment-bridges; and a medium of the fluvial interchange. Some design experimentations delineate the principles of a critical continuity in which renewal means belonging to the stratification of the history of the places.

Entrepreneurship is very important in a society due to its influence with the growth and development of a country. The importance of studying and knowing the entrepreneurial activity and the entrepreneur's profile contributes positively to identify estimates of this activity and to clarify the future of this process. In this sense, this article presents the evolution of entrepreneurship in Brazil over the past 13 years, using for the study secondary data obtained from the GEM and IBGE researches, in which the search was conducted in documentary basis from 2001 to 2013. The results present a descriptive analysis of the Global Entrepreneurship Monitor entrepreneurship indicators (GEM) concerning to the new entrepreneur rate and the rate of nascent entrepreneurs, growth of the Brazilian GDP related to entrepreneurship, entrepreneurship rate according to the entrepreneur stages (initial and established), initial entrepreneurs according to their motivation (by chance and necessity), by gender entrepreneurs, age, level of education. It was also carried out statistical analysis where the trend of the variables over time was verified by simple linear regression at the significance level of 5%. The study concludes that Brazil tends to present significant growth towards entrepreneurship, an advancement of the female contribution to the economy, increase of entrepreneurs because of more opportunities and stability in the existing businesses.

This work presents a study on the effect of sliding distance on abrasive wear modes transition in micro-abrasive wear. Ball-cratering wear tests were conducted with specimens of P20 cemented carbide (WC-Co) and M2 tool steel, balls of 52100 steel and abrasive slurry prepared with SiC particles and distilled water. Results were analyzed in terms of Ag (area with grooving abrasion) and Ar (area with rolling abrasion) as a function of sliding distance and pressure; they have indicated that with the increasing of sliding distance and, a consequent decreasing of pressure, there is the transition from grooving abrasion to rolling abrasion.

BACKGROUND: An epidemic of asbestos-related disease is ongoing in most industrialized countries, mainly attributable to past occupational exposure but partly due to environmental exposure. In this perspective, the incidence of pleural mesothelioma close to a former asbestos-cement plant in a national contaminated site was estimated. METHODS: The census-tracts interested by atmospheric dispersion of facilities in the contaminated site were identified. Two subareas with different estimated environmental asbestos impact were distinguished. An ecological study at micro-geographic level was performed. The standardized incidence ratios (SIR) for study area and the two subareas, in comparison with region and municipality were computed. The standardized incidence rate ratio (IRR) between the two subareas was computed. RESULTS: Mesothelioma incidence in the study area was increased: 46 cases were observed with respect to 22.23 expected (SIR: 2.02). The increase was confirmed in analysis considering only the subjects without an occupationally exposure to asbestos: 19 cases among men (SIR = 2.48; 95% CI: 1.49-3.88); 11 case among women (SIR = 1.34; 95% CI: 0.67-2.40). The IRR between the two subareas is less than one in overall population considering all age-classes and of 3 fold (IRR = 3.14, 95% CI: 0.65-9.17) in the age-classes below 55 years. CONCLUSIONS: The findings indicate an increased incidence of pleural mesothelioma in the neighbourhood of asbestos-cement plant, and a possible etiological contribution of asbestos environmental exposure in detected risks.

The purpose of this qualitative study was: (a) to explore the cognitive and metacognitive processes of mathematics problem-solving discourse of 10-year-old students in Russia, Spain, Hungary, and the United States; and (b) to explore the patterns of social interactions during small group work. Data were analyzed using a cognitive/metacognitive framework adopted from Artzt and Armour-Thomas. The analysis of think-aloud transcripts, students' reflective journals, and field observation notes revealed similar patterns of cognitive/metacognitive processes of the problem-solving discourse at the four research sites and distinct patterns of social interactions. Implications of how children used metacognition to impact learning during mathematics problem solving are discussed.

The purpose of this work is to present a ball-cratering equipment configuration to measure the coefficient of friction. Two load cells were used to measure, in real time, the “normal” and “tangential” forces during the experiments to calculate the coefficient of friction. Micro-abrasive wear tests were conducted on an AISI H10 tool steel specimen, with a ball of AISI 52100 steel and an abrasive slurry, prepared with SiC and distilled water; different values of normal force and sliding distance were defined for the wear experiments to investigate and validate the constructed machine. The results showed that due to test conditions, it was observed the occurrence of rolling abrasion. The equipment showed excellent functionality and reproducibility, in terms of formation of the wear craters and measurement of the coefficient of friction.

Many times teachers hear students say: "Why are we learning this? Why do we have to know this? When are we going to use this outside of class time?" These common questions are probably familiar to most high school teachers. An 11th-grade English teacher attended a university-school district professional development (PD) program on interdisciplinary mathematics to gain insight on how to answer these students' questions and develop a new perspective on implementing "interdisciplinary"--also called "integrative"--curriculum. When applying PD program concepts, the English teacher integrated solid and plane geometry in an interdisciplinary manner during a study of "The Scarlet Letter" (2004) by Nathaniel Hawthorne in his self-contained 11th-grade class. This analysis of his strategy provides supporting research, summarizes an interdisciplinary approach for classroom use, integrates an assessment strategy, and generalizes the approach for multiple interdisciplinary projects. (Contains 2 tables and 2 figures.)

Neutron scattering in combination with scanning electron and atomic force microscopy were employed to quantitatively resolve elemental composition, nano- through meso- to metallurgical structures and surface characteristics of two commercial stainless steel orthodontic archwires—G&H and Azdent. The obtained bulk composition confirmed that both samples are made of metastable austenitic stainless steel type AISI 304. The neutron technique’s higher detection sensitivity to alloying elements facilitated the quantitative determination of the composition factor (CF), and the pitting resistance equivalent number (PREN) for predicting austenite stability and pitting-corrosion resistance, respectively. Simultaneous neutron diffraction analyses revealed that both samples contained additional martensite phase due to strain-induced martensite transformation. The unexpectedly high martensite content (46.20 vol%) in G&H was caused by combination of lower austenite stability (CF = 17.37, p = .03), excessive cold working and inadequate thermal treatment during material processing. Together, those results assist in revealing alloying recipes and processing history, and relating these with corrosion resistance and mechanical properties. The present methodology has allowed access to unprecedented length-scale (μm to sub-nm) resolution, accessing nano- through meso-scopic properties. It is envisaged that such an approach can be extended to the study and design of other metallic (bio)materials used in medical sciences, dentistry and beyond.

Objectives: This review investigated the effects of orthodontic or functional orthopedic therapy on masseter muscle thickness through the use of ultrasonography (US) in growing subjects when compared with untreated subjects. Materials and Methods: This review systematically assessed studies that investigated growing subjects undergoing orthopedic therapy for the correction of malocclusion of vertical, sagittal and transversal plane. Electronic databases (CENTRAL, MEDLINE-PubMed, Scopus and Web of Science) were searched up to February 2019, including available RCTs and CCTs, without language restrictions. The primary outcome was the effect of orthopedic or functional treatment on masseter muscle thickness. The risk of bias of included studies was assessed through the Newcastle-Ottawa quality assessment scale with the aim of defining their methodological quality. A random-effects meta-analysis analyzing mean differences with 95% confidence intervals was used for quantitative analysis. Results: The search retrieved 749 titles, but the studies selection resulted in a final sample of 5 CCTs. The studies retrieved data from 233 children (age range: 5−22 years) and were conducted at university dental clinics. Children were treated for Class II malocclusion, increased vertical dimension or lateral cross-bite variably with rapid or slow maxillary expansion, twin block, bite block, mandibular activators, quad helix, alone or in combination. Risk of bias was assessed as medium for three studies, low for one and high for another. The meta-analysis determined that at the end of orthopedic or functional treatment masseter muscle thickness, measured through the use of US, is significantly reduced (MD −0.79 mm; 95% CI −1.28 to −0.31). The reduction in muscle thickness, therefore, could be considered an indicator for the evaluation of the success of therapy with orthodontic appliances. Conclusions: Although the meta-analysis revealed that US could be considered a less invasive and effective method to evaluate the masseter muscle thickness, single-blinded RCTs, are required to confirm US reliability in this field of application. This review was registered on PROSPERO with the following registration number: CRD42018068402.

INTRODUCTION: Bacillus cereus, a ubiquitous bacterium, can be isolated in various starchy food items, causing both emetic and diarrhoeal disease. The real burden of B. cereus outbreaks is actually poorly known in Italy. We report a B. cereus foodborne outbreak that occurred in a pub in Bari (Italy) on January 22nd 2012 during a birthday party, promptly reported by the pub owner. MATERIALS AND METHODS: Between January 22nd and 24th 2012, we performed a retrospective cohort study among the guests of the party to identify risk factors associated with illness. Leftovers of different meals were available for microbiological analysis. Faecal specimens were collected from cases. RESULTS: A total of 12 cases among the 13 customers (attack rate: 92%) were reported. All cases had consumed basmati rice and sweet and sour vegetables (aetiological fraction: 100%). B. cereus was isolated from both basmati rice served during the party and faecal specimens. DISCUSSION: The close collaboration between the pub owner and the public health officers and the possibility to test food leftovers and stool samples contributed to prevent further cases.

A Professional Development School (PDS) serves as a quality-teaching model. It is a vehicle that generates professional understanding through conversations among university professors, teachers, and teacher candidates. The author illustrates a pilot PDS program that exemplifies the many benefits of transforming the teaching model into a successful collaboration and the lessons learned by PDS participants. The partnership explores classroom culture, collaboration agendas, and quality efforts for building a conceptual framework for mathematics and science teaching and learning with fifth graders. (Contains 1 table and 1 figure.)

For thousands of years military children have been faced with many challenges that result from the combat deployment of their parents. These challenges are likely to be particularly burdensome to infants, toddlers, and preschoolers because of their emotional and cognitive immaturity, their reliance on magical thinking, and their dependence upon their parents for healthy development. This article outlines the challenges that modern young military children face, focusing on parental combat deployment, parental combat injury, parental postcombat health consequences, and parental death. Readers are reminded of the unique needs of young military children and the culturally informed services that are necessary for them to overcome these challenges.

This article aimed to investigate the effects of mental training on volleyball players service performance. Six male volleyball players aged from 18 to 25 years old of a team from the interior of São Paulo’s state were studied. The service performance was evaluated in three different championships of the same season. The services were scored in game situations at the same time of the intervention process. The measure means indicated service performance increased with the mental training practice, with more services performed correctly and less mistakes at the end of the intervention process. The mistakes dimished significantly from the baseline to the final of the intervention process and from the start of the intervention process to its final.

The micro-abrasive wear tests by rotating ball (crater wear) have played an important role in abrasive wear researches. In this type of test, the contact between a specimen and a ball on rotating motion and abrasive particles supplied between these two elements, results in a crater on the specimen, based on which the abrasive wear behaviour is analysed. The purpose of this work is to study results the reprodutibility and the silicon carbide (SiC) abrasive particles fragmentation during micro-abrasive wear tests. Tests were conducted with carburized AISI 1010 steel balls and high speed steel specimens, “with” and “without” titanium nitride (TiN) coatings. The abrasive slurry was prepared with black silicon carbide (average particle size of 5 µm) and distilled water. Grooving abrasion is related with lower reprodutibility results. For the test conditions of this work, no abrasive particles fragmentation was observed, independently of the sliding distance, what is justified, among others factors, by the low normal force applied.

Introduction: Although the pathophysiology of the testicular damage associated with varicocele remains unclear, sperm DNA damage has been identified as a potential explanation for this cause of male infertility. The current study was designed to determine the extent of sperm nuclear DNA damage in patients with varicocele, and to examine its relationship with parameters of seminal motility. Materials and method: Semen samples from 60 patients with clinical varicocele and 90 infertile men without varicocele were examined. Varicocele sperm samples were classified as normal or pathological according to the 1999 World Health Organizzation guidelines. Sperm DNA damage was evalutated using the Halosperm kit, an improved Sperm Chromatin Dispersion (SCD) test. Results: The DNA fragmentation index (DFI: percentage of sperm with denatured nuclei) values was significantly higher in patients with varicocele, either with normal or abnormal (DFI 25.8 ± 3.2 vs 17.4 ± 2.8 - P < 0,01) semen profiles. In addition, an inverse correlation was found between spermatic motility and the degree of spermatic DNA fragmentation in patients with clinical varicocele. Conclusions: Varicocele is associated with high levels of DNA-damage in spermatozoa. In addition, in subjects with varicocele, abnormal spermatozoa motility is associated with higher levels of sperm DNA fragmentation. DNA fragmentation may therefore be an essential additional diagnostic test that should be recommended for patients with clinical varicocele.

OBJECTIVES: Force platforms are widely used to evaluate the relationship between posture and dental occlusion. This study evaluated whether force platforms are able to detect eventual postural modifications resulting from dental occlusion. METHOD: A total of 44 healthy volunteers who were given no information on the aim of the study underwent six postural stabilometric exams under different mandibular and visual conditions. Four parameters were considered: sway area, sway velocity, X axis displacement of the center of the foot pressure and Y axis displacement of the center of the foot pressure. RESULTS: An analysis of variance (ANOVA) revealed the relative influence of each factor; specifically, the ocular afference significantly influenced the sway area and sway velocity parameters, and the mandibular position had only aweakinfluence on theswayareaparameter. CONCLUSIONS: Vision was shown to influence body posture, and a weak correlation was observed between mandibular position and body posture in healthy subjects. However, the force platform is most likely not able to clearly detect this relationship. Gnathologists must use caution when using force platform analysis to modify a therapeutic plan. The sway area seems to be the most sensitive parameter for evaluating the effect of occlusion on body posture.

Introduction: This study aimed to analyze the variation of dentoskeletal effects after rapid maxillary expander therapy in subjects with different vertical growth patterns.Methods: The study sample consisted of 94 patients (32 males, 62 females; mean age 8.9 ± 1.5 years) treated with rapid maxillary expander (RME) anchored on first permanent molars. For each subject, lateral cephalograms and maxillary digital dental casts were available before RME, immediately after appliance removal, and 1 year after appliance removal. All the subjects were divided into 3 groups according to their vertical facial patterns (low-angle, normal-angle, and high-angle). Cephalometric analysis was conducted on lateral cephalograms. The virtual 3-dimensional models were used to analyze the torque of the first permanent molars and intercanine and intermolar width. The differences between the vertical facial subgroups were contrasted by analysis of variance multicomparison test (P <0.05).Results: In the short-term (from before to immediately after RME removal), high-angle subjects showed a mandibular clockwise rotation compared with other groups. No significant long-term vertical and sagittal skeletal changes (from before to 1 year after RME removal) were found between the groups. A greater increase in maxillary molar torque was observed in high-angle subjects than in the other groups. The low-angle patients showed a greater increase in the intercanine diameter.Conclusions: Hyperdivergent subjects showed increased buccal tipping of the anchor molars after the expansion. Hypodivergent and normodivergent subjects showed lower buccal tipping after the expansion and an increased expansion effect in the anterior region. [ABSTRACT FROM AUTHOR]