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Concept: Major


The ant genus Pheidole-for all of its hyperdiversity and global ubiquity-is remarkably conservative with regard to morphological disparity. A striking exception to this constrained morphology is the spinescent morphotype, which has evolved multiple times across distantly related lineages of Indoaustralian Pheidole. The Pheidole cervicornis group contains perhaps the most extraordinary spinescent forms of all Pheidole. Here we present a taxonomic revision of the P. cervicornis group, and use microtomographic scanning technology to investigate the internal anatomy of the thoracic spines. Our findings suggest the pronotal spines of Pheidole majors, are possibly skeletomuscular adaptations for supporting their disproportionately large heads. The ‘head support hypothesis’ is an alternative to the mechanical defense hypothesis most often used to explain spinescence in ants. The P. cervicornis group is known only from New Guinea and is represented by the following four species, including two described here as new: P. barumtaun Donisthorpe, P. drogon sp. nov., P. cervicornis Emery, and P. viserion sp. nov. The group is most readily identified by the minor worker caste, which has extremely long pronotal spines and strongly bifurcating propodeal spines. The major and minor workers of all species are illustrated with specimen photographs, with the exception of the major worker of P. cervicornis, which is not known.

Concepts: Evolution, Species, Insect, Major, Ant, Hymenoptera, Minor scale, Minor chord


Studies examining the relation of information processing speed, as measured by reaction time, with mortality are scarce. We explored these associations in a representative sample of the US population.

Concepts: Sample, Mortality rate, Sample size, Sampling, Demography, Information, Cultural studies, Major


Introduction: Raypex 6 is an electronic apex locator (EAL) that has not yet been tested in vivo. The purpose of this in vivo study was to compare the accuracy of two EALs: the Dentaport ZX and the Raypex 6. Methods: The study involved 36 straight single-rooted teeth. A 10-K file was advanced until the EAL detected the major foramen. The file was fixed in a replaceable pattern of light-cured composite. The apical part of each canal was trimmed to expose the file tip. The distances from the file tips to the major foramen were measured. Results: Wilcoxon’s signed Rank test found no significant differences between the Dentaport ZX and Raypex 6 in terms of their abilities to detect the major foramen (P = .52) The Dentaport ZX was accurate 82.35% of the time to ± 0.5 mm and 97.05% of the time to ± 1 mm, whereas the Raypex 6 was accurate 88.22% of the time to ± 0.5 mm and 100% of the time to ± 1 mm. Conclusions: No statistically significant differences were observed between the performance of the Dentaport ZX and Raypex 6 EALs under the in vivo clinical conditions used in this study.

Concepts: Statistics, Measurement, Statistical significance, In vivo, Psychometrics, Major, Significant figures, Military rank


The emphasis placed on the activities of mobile teams in the detection of gambiense human African trypanosomiasis (HAT) can at times obscure the major role played by fixed health facilities in HAT control and surveillance. The lack of consistent and detailed data on the coverage of passive case-finding and treatment further constrains our ability to appreciate the full contribution of the health system to the control of HAT.

Concepts: Parasitic diseases, Trypanosoma brucei, African trypanosomiasis, Major, Trypanosome, Tsetse fly, Sleeping sickness, ObsCure II


Worldwide, leprosy is one of the major causes of preventable disability. India contributes to 60% of global leprosy burden. With increasing numbers of leprosy with grade 2 disability (visible disability) at diagnosis, we aimed to determine risk factors associated with grade 2 disability among new cases and explore patients and providers' perspectives into reasons for late presentation.

Concepts: Health care provider, Medical terms, Patient, Physician, Illness, Major


We sought to obtain novel insights into schizophrenia pathogenesis by exploiting the association between the disorder and chromosomal copy number (CNV) burden. We combined data from 5,745 cases and 10,675 controls with other published datasets containing genome-wide CNV data. In this much-enlarged sample of 11,355 cases and 16,416 controls, we show for the first time that case CNVs are enriched for genes involved in GABAergic neurotransmission. Consistent with non-genetic reports of GABAergic deficits in schizophrenia, our findings now show disrupted GABAergic signaling is of direct causal relevance, rather than a secondary effect or due to confounding. Additionally, we independently replicate and greatly extend previous findings of CNV enrichment among genes involved in glutamatergic signaling. Given the strong functional links between the major inhibitory GABAergic and excitatory glutamatergic systems, our findings converge on a broad, coherent set of pathogenic processes, providing firm foundations for studies aimed at dissecting disease mechanisms.

Concepts: Gene, Genetics, Bacteria, Copy number variation, Neuroscience, Case, Major


Synaesthetic people are probably more numerous than usually thought. This unique sensory phenomenon may concern up to 4% of the general population. Physicians are not very aware of synaesthesias because synaesthetes ignore themselves and most often consider this perceptive faculty as common and not pathological. We report in detail a grapheme-phoneme to colour developmental synaesthesia in a 54-year-old woman. The major contribution of research over the last two decades is also summarized.

Concepts: Psychology, Greek loanwords, Color, Major, Qualia, Synesthesia, Women's suffrage, Field officer


The aim of this study was to report the trends in provision of cholecystectomy in the National Health System in England over the 9 year period from 2000 to 2009 and to determine the major risk factors associated with subsequent poor outcome.

Concepts: Medicine, Universal health care, Public health, Epidemiology, 1920, Major, Trigonometric functions


Study Design. Retrospective case control study.Objective. To evaluate the effectiveness of bracing in patients with Chiari malformation-associated scoliosis (CMS) following posterior fossa decompression (PFD).Summary of Background Data. The effectiveness of bracing has been poorly studied in CMS patients who have received PFD.Methods. A retrospective study was conducted on 22 CMS patients who received brace treatment for their scoliosis following PFD. Forty-four age- and gender-matched IS patients who received bracing served as the control group. The bracing outcome was considered a failure if the curve worsened ≥ 6°; otherwise, the treatment was considered to be successful.Results. The age and Risser grade were similar between the CMS and IS patients at brace initiation. The initial curve magnitude of CMS patients (mean, 32.9° ± 6.3°; range, 20°-45°) was marginally significantly larger than that of the IS patients (mean, 29.6° ± 6.4°; range, 20°-45°). Until the final follow-up, a ≥ 6° worsening of the major curve occurred in 8 CMS patients (36%) and in 15 IS patients (34%). Overall, 7 CMS patients (32%) and 13 IS patients (30%) underwent spinal fusion surgery. No significant differences were observed between the two groups in the surgery rates or the bracing success rates (P>0.05). In the CMS patients, neither the performance of syringosubarachnoid shunting nor the extent of tonsillar descent correlated with the bracing outcomes, whereas a double major curve pattern was found to be predictive for the failure of bracing.Conclusion. Brace treatment subsequent to PFD is effective in preventing curve progression for 64% of CMS patients, which is comparable to the rate that is observed in IS patients. Double major curve pattern may be a risk factor in predicting treatment failure in CMS patients.

Concepts: Scientific method, Vertebral column, Scoliosis, The Age, Retrospective, Major, Spinal fusion, Scheuermann's disease


Pneumatic dilation (PD) and laparoscopic Heller myotomy (LHM) can be definitive therapies for achalasia; recent data suggest comparable efficacy. However, risk must also be considered. We reviewed the major complication rate of PD and LHM in a high-volume center and reviewed the corresponding literature.

Concepts: Surgery, Review, Major, Achalasia, Heller myotomy, Esophageal dilatation