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Predicting wins, losses and attributes' sensitivities in the soccer World Cup 2018 using neural network analysis
Predicting the results of soccer competitions and the contributions of match attributes, in particular, has gained popularity in recent years. Big data processing obtained from different sensors, cameras and analysis systems needs modern tools that can provide a deep understanding of the relationship between this huge amount of data produced by sensors and cameras, both linear and non-linear data. Using data mining tools does not appear sufficient to provide a deep understanding of the relationship between the match attributes and results and how to predict or optimize the results based upon performance variables. This study aimed to suggest a different approach to predict wins, losses and attributes' sensitivities which enables the prediction of match results based on the most sensitive attributes that affect it as a second step. A radial basis function neural network model has successfully weighted the effectiveness of all match attributes and classified the team results into the target groups as a win or loss. The neural network model's output demonstrated a correct percentage of win and loss of 83.3% and 72.7% respectively, with a low Root Mean Square training error of 2.9% and testing error of 0.37%. Out of 75 match attributes, 19 were identified as powerful predictors of success. The most powerful respectively were: the Total Team Medium Pass Attempted (MBA) 100%; the Distance Covered Team Average in zone 3 (15-20 km/h; Zone3_TA) 99%; the Team Average ball delivery into the attacking third of the field (TA_DAT) 80.9%; the Total Team Covered Distance without Ball Possession (Not in_Poss_TT) 76.8%; and the Average Distance Covered by Team (Game TA) 75.1%. Therefore, the novel radial based function neural network model can be employed by sports scientists to adapt training, tactics and opposition analysis to improve performance
Association between diverticulosis and colonic neoplastic lesions in individuals with a positive faecal immunochemical test
Background The association between diverticulosis and colonic neoplastic lesions has been suggested, but data in literature are conflicting. This study aimed to investigate such a relationship in patients participating in a colorectal cancer screening program who underwent high-quality colonoscopy.Methods Data from consecutive individuals 50-75 years of age with a positive faecal immunological test were considered. Diverticulosis was categorised as present or absent. The prevalence of neoplastic lesions (adenoma, advanced adenoma, and cancer) between individuals with and those without diverticula was compared. A multivariate analysis was performed.Results Overall, data from 970 consecutive individuals were evaluated, and diverticulosis was detected in 354 (36.5%) cases. At least one adenoma was detected in 490 (50.5%) people, at least one advanced adenoma in 264 (27.2%), multiple adenoma in 71 (7.3%), whilst a cancer was diagnosed in 48 (4.9%) cases. At univariate analysis, the adenoma detection rate in patients with diverticula was significantly higher than in controls (55.9% vs 47.4%; p=0.011). At multivariate analysis, presence of diverticulosis was an independent risk factor for both adenoma detection rate (OR=1.58; 95% CI=1.14-2.18; p=0.006) and advanced adenoma (OR=1.57; 95% CI=1.10-2.24; p=0.013), but not for colorectal cancer.Conclusions In a colorectal screening setting, the adenoma detection rate was significantly higher in individuals with diverticulosis than in controls
Strain and field modulation in bilayer graphene band structure
Using an external electric field, one can modulate the bandgap of Bernal
stacked bilayer graphene by breaking A-~B symmetry. We analyze strain effects
on the bilayer graphene using the extended Huckel theory and find that reduced
interlayer distance results in higher bandgap modulation, as expected.
Furthermore, above about 2.5 angstrom interlayer distance, the bandgap is
direct, follows a convex relation to electric field and saturates to a value
determined by the interlayer distance. However, below about 2.5 angstrom, the
bandgap is indirect, the trend becomes concave and a threshold electric field
is observed, which also depends on the stacking distance.Comment: 3 pages, 5 figures - v1 and v2 are the same, uploaded twice - v3,
some typos fixed and a reference adde
High concordance between trained nurses and gastroenterologists in evaluating recordings of small bowel video capsule endoscopy (VCE)
Background & Aims: The video capsule endoscopy (VCE) is an accurate and validated tool to investigate the entire small bowel mucosa, but VCE recordings interpretation by the gastroenterologist is time-consuming. A pre-reading of VCE recordings by an expert nurse could be accurate and cost saving. We assessed the concordance between nurses and gastroenterologists in detecting lesions on VCE examinations. Methods: This was a prospective study enrolling consecutive patients who had undergone VCE in clinical practice. Two trained nurses and two expert gastroenterologists participated in the study. At VCE pre-reading the nurses selected any abnormalities, saved them as “thumbnails” and classified the detected lesions as a vascular abnormality, ulcerative lesion, polyp, tumor mass, and unclassified lesion. Then, the gastroenterologist evaluated and interpreted the selected lesions and, successively, reviewed the entire video for potential missed lesions. The time for VCE evaluation was recorded. Results: A total of 95 VCE procedures performed on consecutive patients (M/F: 47/48; mean age: 63 ± 12 years, range: 27−86 years) were evaluated. Overall, the nurses detected at least one lesion in 54 (56.8%) patients. There was total agreement between nurses and gastroenterologists, no missing lesions being discovered at a second look of the entire VCE recording by the physician. The pre-reading procedure by nurse allowed a time reduction of medical evaluation from 49 (33-69) to 10 (8-16) minutes (difference:-79.6%). Conclusions: Our data suggest that trained nurses can accurately identify and select relevant lesions in thumbnails that subsequently were faster reviewed by the gastroenterologist for a final diagnosis. This could significantly reduce the cost of VCE procedure
Interacting spin-2 fields in three dimensions
Using the frame formulation of multi-gravity in three dimensions, we show
that demanding the presence of secondary constraints which remove the
Boulware-Deser ghosts restricts the possible interaction terms of the theory
and identifies invertible frame field combinations whose effective metric may
consistently couple to matter. The resulting ghost-free theories can be
represented by theory graphs which are trees. In the case of three frame
fields, we explicitly show that the requirement of positive masses and energies
for the bulk spin-2 modes in AdS is consistent with a positive central
charge for the putative dual CFT.Comment: 26 pages, 3 figures, v2: minor changes, matches published versio
Accuracy of Circulation Estimation Schemes Applied to Discretised Velocity Field Data
Numerical experiments are conducted on the velocity field of the Oseen vortex to determine the effect of random errors in the velocity field on the circulation estimate. The circulation is estimated by either a velocity integral or a vorticity integral over a particular region of integration. A novel method for the determination of this region is used. The accuracy of circulation estimation schemes is characterised in terms of the velocity sample spacing, the amount of random noise in the velocity field and the vorticity estimation scheme used. It is found that, in general, the velocity integral outperforms the vorticity integral in terms of reducing total error
Nonvolatile memory with molecule-engineered tunneling barriers
We report a novel field-sensitive tunneling barrier by embedding C60 in SiO2
for nonvolatile memory applications. C60 is a better choice than ultra-small
nanocrystals due to its monodispersion. Moreover, C60 provides accessible
energy levels to prompt resonant tunneling through SiO2 at high fields.
However, this process is quenched at low fields due to HOMO-LUMO gap and large
charging energy of C60. Furthermore, we demonstrate an improvement of more than
an order of magnitude in retention to program/erase time ratio for a metal
nanocrystal memory. This shows promise of engineering tunnel dielectrics by
integrating molecules in the future hybrid molecular-silicon electronics.Comment: to appear in Applied Physics Letter
Zero Temperature Insulator-Metal Transition in Doped Manganites
We study the transition at T=0 from a ferromagnetic insulating to a
ferromagnetic metallic phase in manganites as a function of hole doping using
an effective low-energy model Hamiltonian proposed by us recently. The model
incorporates the quantum nature of the dynamic Jahn-Teller(JT) phonons strongly
coupled to orbitally degenerate electrons as well as strong Coulomb correlation
effects and leads naturally to the coexistence of localized (JT polaronic) and
band-like electronic states. We study the insulator-metal transition as a
function of doping as well as of the correlation strength U and JT gain in
energy E_{JT}, and find, for realistic values of parameters, a ground state
phase diagram in agreement with experiments. We also discuss how several other
features of manganites as well as differences in behaviour among manganites can
be understood in terms of our model.Comment: To be published in Europhysics Letter
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