Existence of the D0-D4 Bound State: a detailed Proof

We consider the supersymmetric quantum mechanical system which is obtained by dimensionally reducing d=6, N=1 supersymmetric gauge theory with gauge group U(1) and a single charged hypermultiplet. Using the deformation method and ideas introduced by Porrati and Rozenberg, we present a detailed proof of the existence of a normalizable ground state for this system

Integration of production and financial models to analyse the financial impact of livestock diseases: a case study of Schmallenberg virus disease on British and French dairy farms

AIMS AND OBJECTIVES: The aim of the study was to investigate and compare the financial impact of Schmallenberg disease for different dairy production types in the United Kingdom and France. MATERIALS AND METHODS: Integrated production and financial models for dairy cattle were developed and applied to Schmallenberg virus (SBV) disease in a British and French context. The five main production systems that prevail in these two countries were considered. Their respective gross margins measuring the holding's profitability were calculated based on public benchmarking, literature and expert opinion data. A partial budget analysis was performed within each production model to estimate the impact of SBV in the systems modelled. Two disease scenarios were simulated: low impact and high impact. RESULTS: The model gross margin obtained per cow space and year ranged from £1014 to £1484 for the UK and from £1037 to £1890 for France depending on the production system considered. In the UK, the net SBV disease costs in £/cow space/year for an average dairy farm with 100 milking spaces were estimated between £16.3 and £51.4 in the high-impact scenario and between £8.2 and £25.9 in the low-impact scenario. For France, the net SBV disease costs in £/cow space/year ranged from £19.6 to £48.6 in the high-impact scenario and £9.7 to £22.8 in the low-impact scenario, respectively. CONCLUSION: The study illustrates how the combination of production and financial models allows assessing disease impact taking into account differing management and husbandry practices and associated price structures in the dairy sector. It supports decision-making of farmers and veterinarians who are considering disease control measures as it provides an approach to estimate baseline disease impact in common dairy production systems in the UK and France

Induced mass in N=2 super Yang-Mills theories

The masses of the matter fields of N=2 Super-Yang-Mills theories can be defined as parameters of deformed supersymmetry transformations. The formulation used involves central charges for the matter fields. The explicit form of the deformed supersymmetry transformations and of the invariant Lagrangian in presence of the gauge supermultiplet are constructed. This works generalizes a former one, due to the same authors, which presented the free matter case.Comment: 15 pages, Late

Nonlinear Circuit Analysis via Perturbation Methods and Hardware Prototyping

Nonlinear signal processing is necessary in many emerging applications where form factor and power are at a premium. In order to make such complex computation feasible under these constraints, it is necessary to implement the signal processors as analog circuits. Since analog circuit design is largely based on a linear systems perspective, new tools are being introduced to circuit designers that allow them to understand and exploit circuit nonlinearity for useful processing. This paper discusses two such tools, which represent nonlinear circuit behavior in a graphical way, making it easy to develop a qualitative appreciation for the circuits under study

Ultrastructure of grape leaf protoplasts in comparison with the source tissue

Based on their histochemical properties, protoplasts from grape leaf mesophyll were found to be viable and devoid of remnants of the cell wall. The results were confirmed by electron microscopy of sectioned and freeze-etched protoplast preparations. The only remarkable difference between cells in the intact tissue and the protoplasts was the occurrence of electron-dense globules in the cytoplasm of some individuals. These "osmiophilic bodies" are believed to be due to inevitable plasmolytic effects during wall removal and seem not to have any influence on protoplast CO2-assimilation, as has been demonstrated earlier. lt therefore appears that the vital structures remain intact and functional, in spite of the stress situation created by the isolation procedure.Ultrastruktur von Rebenblatt-Protoplasten und Ausgangsgewebe - ein VergleichAnhand histochemischer Nachweise, welche das Weiterfunktionieren der Plasmamembran als physiologische Barriere nach dem Isolationsprozeß bestätigen, können Mesophyllprotoplasten von Vitis vinifera L. als lebensfähig betrachtet werden. Dieser Befund, sowie das vollständige Fehlen von Zellwandresten, wurde durch elektronenmikroskopische Untersuchungen an Ultradünnschnitten bzw. Gefrierätzproben von Protoplastenpräparaten erhärtet. Das vereinzelte Auftreten von elektronendichten, runden Gebilden (sog. osmiophilic bodies) im Cytoplasma ist vermutlich eine der plasmolysierenden Wirkung des Isolationsmediums zuzuschreibende Erscheinung. Wie früher gezeigt, hat aber die verwendete Isolationsmethodik keinen negativen Einfluß auf den photosynthetischen C-Stoffwechsel der Protoplasten. Daraus geht hervor, daß die lebenswichtigen Zellkomponenten, trotz der isolationsbedingten Streßsituation, keinen irreversiblen und damit nachweisbaren, strukturellen oder funktionellen Beeinträchtigungen unterworfen sind

Serious bacterial infections in patients with rheumatoid arthritis under anti‐TNF‐α therapy

Objective. With rising numbers of anti‐tumour necrosis factor α (TNF‐α) treatments for rheumatoid arthritis (RA), Crohn's disease and other conditions, physicians unaware of potential pitfalls are increasingly likely to encounter associated severe infections. Our purpose was to assess the incidence and nature of severe infections in our RA patients under anti‐TNF‐α therapy. Methods. We reviewed patient charts and records of the Infectious Disease Unit for serious infections in patients with RA in the 2 yr preceding anti‐TNF‐α therapy and during therapy. Results. Serious infections affected 18.3% of patients treated with infliximab or etanercept. The incidence was 0.181 per anti‐TNF‐α treatment year vs 0.008 in the 2 yr preceding anti‐TNF‐α therapy. In several cases, only a few signs or symptoms indicated the severity of developing infections, including sepsis. Conclusions. A high level of suspicion of infection is necessary in patients under anti‐TNF‐α therapy. We suggest additional strategies for the prevention, rapid identification and pre‐emptive therapy of such infection

N=2 central charge superspace and a minimal supergravity multiplet

We extend the notion of central charge superspace to the case of local supersymmetry. Gauged central charge transformations are identified as diffeomorphisms at the same footing as space-time diffeomorphisms and local supersymmetry transformations. Given the general structure we then proceed to the description of a particular vector-tensor supergravity multiplet of 24+24 components, identified by means of rather radical constraints

The Nature of Online Charter Schools: Evolution and Emerging Concerns

Online charter schools are unique among K-12 online learning options for students. They are full-time, public schools that combine online learning with traditional and home schooling practices. They are often chartered by a state agency, supported in full or in part with state funds and most often managed by a private educational management company. Some extol the virtues of these schools as being able to reach unique student populations at a fraction of the cost borne by traditional public school education. Others are concerned over the lack of evidence supporting the effectiveness of these schools and the problems encountered by young learners who are separated from their teachers due to the online nature of learning in this environment. The goal of this literature review is to: (a) provide a definition of online charter schools; (b) describe their evolution and current status; (c) describe their operations; and, (d) to reveal emerging concerns, including governance, funding and effectiveness. Finally, the authors conclude that there are three significant gaps found in the literature concerning online charter schools and provide recommendations for further research