Fourth Family Neutrinos and the Higgs Boson

We evaluate the LHC discovery potential for the fourth family Standard Model neutrinos in the process $pp\to Z/h\to\nu_{4}{\bar{\nu}_{4}}\to W\mu W\mu$. We show that, depending on their masses, the simultaneous discovery of both the Higgs boson and the heavy neutrinos is probable at early stages of LHC operation. Results are presented for both Majorana and Dirac type fourth family neutrinos.Comment: 12 pages, uses axodraw.sty, v2: includes typo fixes, improved analysis, v4: minor modifications in response to the JHEP refere

Morphometric analysis of the sella turcica in Turkish individuals with different dentofacial skeletal patterns

Background: The aim of this study was to evaluate the morphometric analysis of sella turcica in a Turkish population according to gender, age, and dentofacial skeletal type and to investigate the prevalence of sella turcica shapes in different dentofacial skeletal types. Materials and methods: The lateral cephalometric radiographs of 362 patients (145 males, 217 females) were included and grouped by age, gender, and dentofacial skeletal patterns. Linear dimensions of sella turcica, which include the length, height, and diameter, were measured, and the shapes of sella turcica were evaluated. Results: The anatomical variants of the sella turcica in this study were normal morphology (39.0%), followed by pyramidal shape (15.5%), double contour of floor (14.6%), oblique anterior wall (14.4%), irregular dorsum sella (8.6%), and sella turcica bridge (8.0%). Significant differences were found between sella turcica shapes and dentofacial skeletal types (p < 0.01). Females had greater diameter size of sella turcica than males (p < 0.01). In addition, the subjects in the 15–21 age group had larger sella turcica depths and diameters than the subjects in the 9–14 age group (p < 0.05 and p < 0.01, respectively). However, no significant differences were found between age groups in terms of sella turcica lengths (p > 0.05). Conclusions: Results from this study showed that the sample had a higher rate of morphological variation (39% normal, 61% other types) in comparison with other populations or ethnic groups. The class III patients had more irregularity (notching) types in the posterior part of the dorsum sella and fewer oblique anterior wall types than the others. Linear dimensions and morphological types of sella turcica in this study can be used as reference for additional investigators, such as radiologists, orthodontists, maxillofacial surgeons, and neurosurgeons, to interpret and plan surgical procedures involving the sellar region

Modelling of Gas Transport through Polymer/MOF Interfaces: A Microsecond-Scale Concentration Gradient-Driven Molecular Dynamics Study

Membrane-based separation technologies offer a cost-effective alternative to many energy-intensive gas separation processes, such as distillation. Mixed matrix membranes (MMMs) composed of polymers and metal–organic frameworks (MOFs) have attracted a great deal of attention for being promising systems to manufacture durable and highly selective membranes with high gas fluxes and high selectivities. Therefore, understanding gas transport through these MMMs is of significant importance. There has been longstanding speculation that the gas diffusion behavior at the interface formed between the polymer matrix and MOF particles would strongly affect the global performance of the MMMs due to the potential presence of nonselective voids or other defects. To shed more light on this paradigm, we have performed microsecond long concentration gradient-driven molecular dynamics (CGD-MD) simulations that deliver an unprecedented microscopic picture of the transport of H2 and CH4 as single components and as a mixture in all regions of the PIM-1/ZIF-8 membrane, including the polymer/MOF interface. The fluxes of the permeating gases are computed and the impact of the polymer/MOF interface on the H2/CH4 permselectivity of the composite membrane is clearly revealed. Specifically, we show that the poor compatibility between PIM-1 and ZIF-8, which manifests itself by the presence of nonselective void spaces at their interface, results in a decrease of the H2/CH4 permselectivity for the corresponding composite membrane as compared to the performances simulated for PIM-1 and ZIF-8 individually. We demonstrate that CGD-MD simulations based on an accurate atomistic description of the polymer/MOF composite is a powerful tool for characterization and understanding of gas transport and separation mechanisms in MMMs

Three-dimensional volumetric analysis of the maxillary sinus: a cone-beam computed tomography study

Background: This study aimed to determine the volumetric size of the maxillary sinus and investigate the effect of gender and age on maxillary sinus volume (MSV) using cone-beam computed tomography (CBCT) images in a Turkish subpopulation. Materials and methods: This retrospective volumetric CBCT study was carried out on 133 individuals (84 females, 49 males) between 8 and 51 years old. MSV was measured using the MIMICS 21.0 software (Materialise HQ Technologielaan, Leuven, Belgium). All statistical analyses were performed using the SPSS 21.0 (SPSS, Chicago, IL, USA) software. Mean and standard deviation of both maxillary sinuses measurements were calculated and compared to gender and age. P values < 0.05 were considered to indicate statistical significance. Results: Mean volume of the right maxillary sinus was 13.173 cm3, while for the left was 13.194 cm3. There was no significant difference between right and left maxillary sinus volumes (p > 0.05). There was no significant correlation between MSV and age (p > 0.05). It was found that MSV did not change according to gender (p > 0.05). Conclusions: Right and left maxillary sinus volumes were not different from each other. Gender and age were not found to be related to maxillary sinus volume