Lifting a Realistic SO(10) Grand Unified Model to Five Dimensions

It has been shown recently that the problem of rapid proton decay induced by dimension five operators arising from the exchange of colored Higgsinos can be simply avoided in grand unified models where a fifth spatial dimension is compactified on an orbifold. Here we demonstrate that this idea can be used to solve the Higgsino-mediated proton decay problem in any realistic SO(10) model by lifting that model to five dimensions. A particular SO(10) model that has been proposed to explain the pattern of quark and lepton masses and mixings is used as an example. The idea is to break the SO(10) down to the Pati-Salam symmetry by the orbifold boundary conditions. The entire four-dimensional SO(10) model is placed on the physical SO(10) brane except for the gauge fields, the 45 and a single 10 of Higgs fields, which are placed in the five-dimensional bulk. The structure of the Higgs superpotential can be somewhat simplified in doing so, while the Yukawa superpotential and mass matrices derived from it remain essentially unaltered.Comment: 17 pages, version to be published in Phys. Rev. D with expanded discussion of the suppression of dim-5 proton decay operator

Environmental control of asexual reproduction and somatic growth of <i>Aurelia</i> spp. (Cnidaria, Scyphozoa) polyps from the Adriatic Sea

Polyps of two moon jellyfish species, Aurelia coerulea and A. relicta, from two Adriatic Sea coastal habitats were incubated under multiple combinations of temperature (14, 21°C), salinity (24, 37 ppt) and food regime (9.3, 18.6, 27.9 μg C ind−1 week−1) to comparatively assess how these factors may influence major asexual reproduction processes in the two species. Both species exhibited a shared pattern of budding mode (Directly Budded Polyps: DBP; Stolonal Budded Polyps: SBP), with DBP favoured under low food supply (9.3 μg C ind −1 week−1) and low temperature (14°C), and SBP dominant under high temperature (21°C). However, A. coerulea showed an overall higher productivity than A. relicta, in terms of budding and podocyst production rates. Further, A. coerulea exhibited a wide physiological plasticity across different temperatures and salinities as typical adaptation to ecological features of transitional coastal habitats. This may support the hypothesis that the invasion of A. coerulea across coastal habitats worldwide has been driven by shellfish aquaculture, with scyphistoma polyps and resting stages commonly found on bivalve shells. On the contrary, A. relicta appears to be strongly stenovalent, with cold, marine environmental optimal preferences (salinity 37 ppt, T ranging 14–19°C), corroborating the hypothesis of endemicity within the highly peculiar habitat of the Mljet lake. By exposing A. relicta polyps to slightly higher temperature (21°C), a previously unknown developmental mode was observed, by the sessile polyp regressing into a dispersive, temporarily unattached and tentacle-less, non-feeding stage. This may allow A. relicta polyps to escape climatic anomalies associated to warming of surface layers and deepening of isotherms, by moving into deeper, colder layers. Overall, investigations on species-specific eco-physiological and ontogenetic potentials of polyp stages may contribute to clarify the biogeographic distribution of jellyfish and the phylogenetic relationships among evolutionary related sister clades

Slippery customers for conservation: distribution and decline of anguillid eels in South Africa

1. Four anguillid eel species occur in the western Indian Ocean rivers of Africa: Anguilla bengalensis, Anguilla bicolor, Anguilla marmorata and Anguilla mossambica. These catadromous fishes face multiple stressors, including habitat alteration and deterioration, barriers to migration, pollution and the adverse impacts of alien species, but knowledge of eel species occurrence, abundance and ecology in Africa remains poor. 2. This study investigated the present and historical distribution of anguillid eels and the potential associated drivers of declines at the southern extremities of their ranges in South Africa. Data analysed included sampling conducted in KwaZulu–Natal and Eastern Cape between 2015 and 2020, and secondary data extracted from databases, museums and local management agencies. 3. The median extent of inland penetration increased as follows: 22 km for A. bicolor, 29 km for A. marmorata, 94 km for A. bengalensis and 293 km for A. mossambica. The median altitude followed a similar pattern. 4. Extent of occurrence analyses were carried out at the regional level in KwaZulu–Natal. The sampling data on present distribution (2015–2020), compared with historical data, suggests declines in the extents of occurrence of the four eel species in KwaZulu–Natal, ranging between 31 and 48% in the last 30 years and between 35 and 82% since the 1950s. 5. With increasing human threats in the region, especially from watercourse modification and water abstraction, further declines for these species are expected. Conservation measures recommended include the maintenance or restoration of the ecological connectivity of important rivers and the implementation of freshwater protected areas. Although eels are at present not widely exploited in South Africa, there is a need for fisheries regulations to manage sustainable commercial exploitation

Regrafting of the Split-Thickness Skin Graft Donor-Site: Is It Beneficial?

Split-thickness skin grafting remains a fundamental treatment for patients with deep burns and other traumatic injuries. Unfortunately, the donor site wound that remains after split skin graft (SSG) harvesting may also cause problems for the patient; they can lead to discomfort and scars with a poor cosmetic outcome. Regrafting of the donor site is one of the methods described to improve donor site healing and scarring. In this report, we describe a case of a 26-year-old woman with a self-inflicted chemical burn (0.5% TBSA) who underwent split skin grafting. During surgery, only part of the donor site was regrafted with split skin graft remnants. This part healed faster and had a better scar quality at 3 months postsurgery. Nevertheless, the appearance and patients' opinion on the regrafted part deteriorated after 12 months. With this case report, we aim to create awareness of the long-term consequences of regrafting, which may differ from short-time results. Patients expected to have poor reepithelialization potential may benefit from regrafting of the SSG on the donor site. But in healthy young individuals, timewise there would be no benefit since it can lead to an aesthetically displeasing result

Fermion masses in SO(10) with a single adjoint Higgs field

It has recently been shown how to break SO(10) down to the Standard Model in a realistic way with only one adjoint Higgs. The expectation value of this adjoint must point in the B-L direction. This has consequences for the possible form of the quark and lepton mass matrices. These consequences are explored in this paper, and it is found that one is naturally led to consider a particular form for the masses of the heavier generations. This form implies typically that there should be large (nearly maximal) mixing of the mu- and tau-neutrinos. An explanation that does not involve large tan beta also emerges for the fact that b and tau are light compared to the top quark.Comment: 20 pages, LaTeX, clarification of statements about multiple adjoint Higgs fields in the context of superstring theor

SUSY GUTs under Siege : Proton Decay

SO(10) supersymmetric grand unified theories [SUSY GUTs] provide a beautiful framework for physics beyond the standard model. Experimental measurements of the three gauge couplings are consistent with unification at a scale $M_G \sim 3 \times 10^{16}$ GeV. In addition predictive models for fermion masses and mixing angles have been found which fit the low energy data, including the recent data for neutrino oscillations. SO(10) boundary conditions can be tested via the spectrum of superparticles. The simplest models also predict neutron and proton decay rates. In this paper we discuss nucleon decay rates and obtain reasonable upper bounds. A clear picture of the allowed SUSY spectra as constrained by nucleon decay is presented.Comment: 13 page

Treatment of extra-articular proximal and middle phalangeal fractures of the hand: a systematic review

The aim of the study was to systematically review the patient reported and functional outcomes of treatment for extra-articular proximal or middle phalangeal fractures of the hand in order to determine the best treatment options. The review methodology was registered with PROSPERO. A systematic literature search was conducted in electronic bibliographic databases. Two independent reviewers performed screening and data extraction. The evaluation of quality of the included studies was performed using the Structured Effectiveness Quality Evaluation scale. The initial search yielded 2354 studies. The full text manuscripts of 79 studies were evaluated of which 16 studies met the inclusion criteria. In total, 513 extra-articular proximal and middle phalangeal fractures of the hand were included of which 118 (23%) were treated non-operatively, 188 (37%) were treated by closed reduction internal fixation (CRIF) and 207 (40%) by open reduction internal fixation. It can be recommended that closed displaced extra-articular phalangeal fractures can be treated non-operatively, even fractures with an oblique or complex pattern, provided that closed reduction is possible and maintained. Conservative treatment is preferably performed with a cast/brace allowing free mobilization of the wrist. No definite conclusion could be drawn upon whether closed reduction with extra-articular K-wire pinning or transarticular pinning is superior; however, it might be suggested that extra-articular K-wire pinning is favoured. When open reduction is necessary for oblique or spiral extra-articular fractures, lag screw fixation is preferable to plate and screw fixation. But, similar recovery and functional results are achieved with transversally inserted K-wires compared to lag screw fixation. Type of study/level of evidence: therapeutic III

SUSY GUT Model Building

I discuss an evolution of SUSY GUT model building, starting with the construction of 4d GUTs, to orbifold GUTs and finally to orbifold GUTs within the heterotic string. This evolution is an attempt to obtain realistic string models, perhaps relevant for the LHC. This review is in memory of the sudden loss of Julius Wess, a leader in the field, who will be sorely missed.Comment: 24 pages, 14 figures, lectures given at PiTP 2008, Institute for Advanced Study, Princeton, to be published in the European Physical Journal

Treatment of extra-articular proximal and middle phalangeal fractures of the hand: a systematic review

The aim of the study was to systematically review the patient reported and functional outcomes of treatment for extra-articular proximal or middle phalangeal fractures of the hand in order to determine the best treatment options. The review methodology was registered with PROSPERO. A systematic literature search was conducted in electronic bibliographic databases. Two independent reviewers performed screening and data extraction. The evaluation of quality of the included studies was performed using the Structured Effectiveness Quality Evaluation scale. The initial search yielded 2354 studies. The full text manuscripts of 79 studies were evaluated of which 16 studies met the inclusion criteria. In total, 513 extra-articular proximal and middle phalangeal fractures of the hand were included of which 118 (23%) were treated non-operatively, 188 (37%) were treated by closed reduction internal fixation (CRIF) and 207 (40%) by open reduction internal fixation. It can be recommended that closed displaced extra-articular phalangeal fractures can be treated non-operatively, even fractures with an oblique or complex pattern, provided that closed reduction is possible and maintained. Conservative treatment is preferably performed with a cast/brace allowing free mobilization of the wrist. No definite conclusion could be drawn upon whether closed reduction with extra-articular K-wire pinning or transarticular pinning is superior; however, it might be suggested that extra-articular K-wire pinning is favoured. When open reduction is necessary for oblique or spiral extra-articular fractures, lag screw fixation is preferable to plate and screw fixation. But, similar recovery and functional results are achieved with transversally inserted K-wires compared to lag screw fixation. Type of study/level of evidence: therapeutic III

Course of scar quality of donor sites following split skin graft harvesting: Comparison between patients and observers

There exists little to no data on the development of donor-site scars that remain after split skin graft harvesting. The objectives of this study were to (a) examine changes in characteristics of donor-site scar quality over time and (b) assess the agreement between patient-reported and observer-reported donor-site scar quality in a burn population. A prospective cohort study was conducted including patients who underwent split skin grafting for their burn injury. Patients and observers completed the Patient and Observer Scar Assessment Scale (POSAS) for the first harvested donor site at 3 and 12 months post-surgery. This study included 80 patients with a median age of 34 years. At 3 months post-surgery, the patients scored the POSAS items itch and color as most deviant from normal skin, both improved between 3 and 12 months (3.1 vs 1.5 and 5.0 vs 3.5, respectively [P <.001]). Other scar characteristics did not show significant change over time. The patients' overall opinion score improved from 3.9 to 3.2 (P <.001). Observers rated the items vascularization and pigmentation most severe, only vascularization improved significantly between both time points. Their overall opinion score decreased from 2.7 to 2.3 (P <.001). The inter-observer agreement between patients and observers was considered poor (ICC < 0.4) at both time points. Results of current study indicate that observers underestimate the impact of donor-site scars. This has to b