Identification of stingless bees (Hymenoptera: Apidae) in Kenya using Morphometrics and DNA barcoding

Stingless bees are important pollinators of wild plants and crops. The identity of stingless bee species in Africa has not been fully documented. The present study explored the utility of morphometrics and DNA barcoding for identification of African stingless bee populations, and to further employ these tools to identify potential cryptic variation within species. Stingless bee samples were collected from three ecological zones, namely Kakamega Forest, Mwingi and Arabuko-Sokoke Forest, which are geographically distant and cover high, medium and low altitudes, respectively. Forewing and hind leg morphometric characters were measured to determine the extent of morphological variation between the populations. DNA barcodes were generated from the mitochondrial cytochrome c-oxidase I (COI) gene. Principal Component Analysis (PCA) on the morphometric measurements separated the bee samples into three clusters: (1) Meliponula bocandei; (2) Meliponula lendliana + Plebeina hildebrandti; (3) Dactylurina schmidti + Meliponula ferruginea black + Meliponula ferruginea reddish brown, but Canonical Variate Analysis (CVA) separated all the species except the two morphospecies (M. ferruginea reddish brown and black). The analysis of the COI sequences showed that DNA barcoding can be used to identify all the species studied and revealed remarkable genetic distance (7.3%) between the two M. ferruginea morphs. This is the first genetic evidence that M. ferruginea black and M. ferruginea reddish brown are separate species

Uniqueness Theorem for Generalized Maxwell Electric and Magnetic Black Holes in Higher Dimensions

Based on the conformal energy theorem we prove the uniqueness theorem for static higher dimensional electrically and magnetically charged black holes being the solution of Einstein (n-2)-gauge forms equations of motion. Black hole spacetime contains an asymptotically flat spacelike hypersurface with compact interior and non-degenerate components of the event horizon.Comment: 7 pages, RevTex, to be published in Phys.Rev.D1

Ultrarelativistic black hole in an external electromagnetic field and gravitational waves in the Melvin universe

We investigate the ultrarelativistic boost of a Schwarzschild black hole immersed in an external electromagnetic field, described by an exact solution of the Einstein-Maxwell equations found by Ernst (the ``Schwarzschild-Melvin'' metric). Following the classical method of Aichelburg and Sexl, the gravitational field generated by a black hole moving ``with the speed of light'' and the transformed electromagnetic field are determined. The corresponding exact solution describes an impulsive gravitational wave propagating in the static, cylindrically symmetric, electrovac universe of Melvin, and for a vanishing electromagnetic field it reduces to the well known Aichelburg-Sexl pp-wave. In the boosting process, the original Petrov type I of the Schwarzschild-Melvin solution simplifies to the type II on the impulse, and to the type D elsewhere. The geometry of the wave front is studied, in particular its non-constant Gauss curvature. In addition, a more general class of impulsive waves in the Melvin universe is constructed by means of a six-dimensional embedding formalism adapted to the background. A coordinate system is also presented in which all the impulsive metrics take a continuous form. Finally, it is shown that these solutions are a limiting case of a family of exact gravitational waves with an arbitrary profile. This family is identified with a solution previously found by Garfinkle and Melvin. We thus complement their analysis, in particular demonstrating that such spacetimes are of type II and belong to the Kundt class.Comment: 11 pages, REVTeX

Black Holes at the LHC

In these two lectures, we will address the topic of the creation of small black holes during particle collisions in a ground-based accelerator, such as LHC, in the context of a higher-dimensional theory. We will cover the main assumptions, criteria and estimates for their creation, and we will discuss their properties after their formation. The most important observable effect associated with their creation is likely to be the emission of Hawking radiation during their evaporation process. After presenting the mathematical formalism for its study, we will review the current results for the emission of particles both on the brane and in the bulk. We will finish with a discussion of the methodology that will be used to study these spectra, and the observable signatures that will help us identify the black-hole events.Comment: 37 pages, 14 figures, lectures presented in the 4th Aegean Summer School on Black Holes, 17-22 September 2007, Lesvos, Greece, typos corrected, comments and references adde

Higher-level bee classifications (Hymenoptera, Apoidea, Apidae sensu lato)

A higher-level classification of bees, in which the entire group is treated as a single family - the Apidae - is advocated here. A total of seven subfamilies, 51 tribes and 27 subtribes are recognized. These subfamilies correspond to the families adopted in the traditional classification. Although the proposed changes do not involve any major rearrangement, basically only changing the rank given to the main groups, the new system makes the classification of bees more consistent with that adopted for other major groups of aculeate Hymenoptera. It also departs from the 19th century practice, perpetuated in the traditional classification, of giving family-status to the main groups of bees. A correspondence table associating the taxon names used in the current traditional classification with those of the revised classification is presented. Scrapterini new tribe (type-genus Scrapter Lepeletier & Serville) is proposed to accommodate the southern African genus Scrapter.<br>Apresenta-se uma classificação para as abelhas em que o todo o grupo é tratado como uma única família - Apidae. São reconhecidas sete subfamílias, 51 tribos e 27 subtribos. As subfamílias correspondem às famílias da classificação tradicional. Apesar das mudanças propostas afetarem apenas o status dos grupos, o novo sistema torna a classificação das abelhas mais consistente com aquela adotada para os grandes grupos de Hymenoptera aculeados. Além disso, distancia-se da tradição de dar status de família aos grupos principais de abelhas, uma prática do século 19 perpetuada na classificação tradicional. É apresentada uma tabela de correspondência associando os nomes dos táxons usados na classificação tradicional corrente com aquelas da classificação sendo proposta aqui. Scrapterini tribo nova (gênero-tipo Scrapter Lepeletier & Serville) é proposta para acomodar Scrapter, um gênero restrito à porção sul do continente africano

Discomfort and pain during mammography - description, prediction, and prevention

Objective-To identify the nature of pain and discomfort experienced during mammography and how it can be ameliorated. Design-Questionnaire survey before invitation for mammography and immediately after mammography. Responses before screening were related to experience of discomfort. Setting-Health district in South East Thames region. Subjects-1160 women aged 50-64 invited routinely for screening; 774 completed first questionnaire, of whom 617 had mammography. 597 completed the second questionnaire. Main outcome measures-Reported discomfort and pain, comparisons of discomfort with that experienced during other medical procedures, qualitative description of pain with adjective checklist. Results-35% (206/597) of the women reported discomfort and 6% (37/595) pain. 10 minutes after mammography these figures were 4% (24/595) and 0.7% (4/595) respectively. More than two thirds of women ranked having a tooth drilled, having a smear test, and giving blood as more uncomfortable than mammography. The most important predictor of discomfort was previous expectation of pain (discomfort was reported by 21/32 (66%) women who expected pain and 186/531 (35%) who did not). Discomfort had little effect on satisfaction or intention to reattend. Conclusions-The low levels of reported pain and discomfort shortly after mammography and the favourable comparisons with other investigations suggest that current procedures are acceptable. Since two thirds of the women experienced less pain than expected health education and promotion must ensure that accurate information is made available and publicised