History of exotic Meson (4-quark) and Baryon (5-quark) States

I briefly review the history of exotic meson (4-quark) and baryon (5-quark) states, which is rooted in the formalism of Regge pole and duality. There are robust model-independent predictions for the exchange of 4-quark (Baryonium) Regge trajectories in several processes, which are strongly supported by experiment. On the other hand the predictions for the spectroscopy of 4-quark resonances are based on specific QCD inspired models, with some experimental support. The corresponding predictions for the recently discovered exotic baryon (Pentaquark) state are briefly discussed.Comment: 14 pages Latex including 4 eps figures, final version to appear as a topical review in J. Phys.

Neodymium isotope constraints on provenance, dispersal, and climate-driven supply of Zambezi sediments along the Mozambique Margin during the past ∼45,000 years

Marine sediments deposited off the Zambezi River that drains a considerable part of the southeast African continent provide continuous records of the continental climatic and environmental conditions. Here we present time series of neodymium (Nd) isotope signatures of the detrital sediment fraction during the past ~45,000 years, to reconstruct climate-driven changes in the provenance of clays deposited along the Mozambique Margin. Coherent with the surface current regime, the Nd isotope distribution in surface sediments reveals mixing of the alongshore flowing Zambezi suspension load with sediments supplied by smaller rivers located further north. To reconstruct past changes in sediment provenances, Nd isotope signatures of clays that are not significantly fractionated during weathering processes have been obtained from core 64PE304-80, which was recovered just north of the Zambezi mouth at 1329 m water depth. Distinctly unradiogenic clay signatures (ENd values <214.2) are found during the Last Glacial Maximum, Heinrich Stadial 1, and Younger Dryas. In contrast, the Nd isotope record shows higher, more radiogenic isotope signatures during Marine Isotope Stage 3 and between ~15 and ~5 ka BP, the latter coinciding with the timing of the northern hemisphere African Humid Period. The clay-sized sediment fraction with the least radiogenic Nd isotope signatures was deposited during the Holocene, when the adjacent Mozambique Shelf became completely flooded. In general, the contribution of the distinctly unradiogenic Zambezi suspension load has followed the intensity of precession-forced monsoonal precipitation and enhanced during periods of increased southern hemisphere insolation and high-latitude northern hemispheric climate variability

Demineralization Preventive Practices among Nigerian Orthodontists– An Evidence‑based Approach?

Background: The prevalence of white spot lesions/tooth demineralization during orthodontic fixed appliance therapy ranges widely from 2 to 96%&nbsp; of patients. The purpose of this study was to evaluate measures used by orthodontists practicing in Nigeria to manage demineralization during and after fixed orthodontic treatment and how it compares with the available evidence‑based information. Method: Study group comprised of 60 practitioners (21 orthodontists and 39 orthodontic residents) in Nigeria. Self‑administered questionnaires were used to obtain information on the measures they use to prevent the occurrence of demineralization at the onset and during orthodontic treatment, as well as the management of its occurrence at treatment completion. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) software, version 17.0. Descriptive statistics were used. Level of significance was set at P &lt; 0.05. Results: Responses obtained showed that 96.7% of orthodontic practitioners routinely advised their patients on tooth cleaning methods; the use of manual orthodontic toothbrush (78.3%) and dental floss (51.7%) being popularly recommended methods. However, 51.7% used a specific&nbsp; demineralization preventive protocol at the start of treatment. Oral hygiene instruction was observed to be the most commonly adopted protocol (51.7%), followed by fluoride rinses (41.7%) (considered relatively ineffective). Extraoral hygiene instruction was the most common treatment&nbsp; protocol used when tooth demineralization occurred during and after treatment (56.7% and 73.3% respectively). Approximately 92% of the orthodontists agreed on the need for the development of a basic protocol to prevent demineralization. Conclusion: The demineralization preventive measures used by Nigerian orthodontists and orthodontic residents are inconsistent and not based on evidence‑based information. The development of standardized demineralization prevention protocol was therefore recommended. Keywords: Demineralization, oral hygiene, white spot lesion

Alternative Male Mating Behaviors Dependent on Relative Body Size in Captive Oval Squid Sepioteuthis lessoniana (Cephalopoda, Loliginidae)

We observed the reproductive behavior of the oval squid Sepioteuthis lessoniana in captivity. The male used three different mating behaviors: male-parallel (MP), male-upturned (MU) and sneaking. Male competition over females frequently occurred before and during the female egg-laying period, and the outcome of most fights depended on male body size. Larger males guarded their partners from other males and performed MP mating during the egg-laying period of the paired females. In contrast, there was no pairing and mate guarding in MU mating and sneaking, which were adopted by smaller subordinate males as alternative tactics outside female egg-laying period and during the period, respectively. MP matings were 95% successful, but more than half of MU matings were unsuccessful. Higher mating success in MP mating was achieved through pairing, whereas males in MU mating were less successful because mating attempts without pair formation were often foiled by escape of the female. Sneaking was successful in all cases but occurred less frequently. Spermatophores were attached at the opening of the oviduct in MP mating, whereas they were attached around the female buccal membrane in MU mating and sneaking. Considering the route of egg transportation, higher fertilization success can be expected in MP mating because of the advantageous location of the attached spermatophores. Our results suggest that MP mating is used by larger, paired males during the female egg-laying period, and that MU mating and sneaking are alternative tactics adopted by smaller, subordinate males. These alternative mating behaviors would be conditional strategy dependent on relative body size, because some individual males displayed both MP and MU mating behaviors

Attitude and perception of orthodontic patients to orthodontic treatment time and accelerated orthodontics.

Objectives: The purpose of this study was to evaluate the aitude and perception of orthodontic patients to the duration of orthodontic treatment and the procedures for accelerating orthodontic tooth movement.Methods: This was a cross-sectional analytical study. The study population was made up of patients undergoing fixed appliance orthodontic treatment at the Orthodontic Unit of the Lagos University Teaching Hospital. A convenience sampling technique was used and data collection was via selfadministered questionnaires and an information sheet. The questionnaires assessed patients' knowledge of accelerated orthodontic procedures as well as their perception of orthodontic treatment time and willingness to undergo some accelerated orthodontic treatment procedures. The procedures evaluated included corticotomy, piezocision, micro-osteoperforation, laser therapy, local administration of injections and use of vibrations.Results: One hundred orthodontic patients (n=100, adolescents, 46%; adults, 54%) were surveyed comprising 36 males and 64 females. Most of the participants (88%) had never heard of accelerated orthodontics. A majority of respondents (75%) believed that orthodontic treatment time was too long, and were willing to undergo additional procedures to reduce treatment time (81%). Subjects' willingness to undergo the procedures were inversely proportional to the degree of its invasiveness for all groups, with at least a third of the patients willing to accept a 10% increase in treatment fees for a reduction in treatment time across all techniques surveyed.Conclusion: The orthodontic patients surveyed considered treatment time protracted and were interested in undergoing adjunctive orthodontic procedures to accelerate tooth movement, with a consequent increase in treatment cost. They, however, had a limited knowledge of the different methods of accelerating orthodontic treatment. Key words: Accelerated orthodontics, orthodontic treatment tim