Magnetic Charge Can Locally Stabilize Kaluza-Klein Bubbles

We construct a new 2-parameter family of static topological solitons in 5D minimal supergravity which are endowed with magnetic charge and mass. The solitons are asymptotically ${\mathbb R}^4\times S^1$, where the radius of the $S^1$ has a lower bound $R_s\ge R_{min}$. Setting up initial data on a Cauchy slice at a moment of time symmetry, we demonstrate that if $R_s>R_{min}$ these solitons correspond to a perturbatively stable "small" static bubble as well as an unstable "large" static bubble, whereas if $R_s<R_{min}$ there are no static bubbles. The energetics and thermodynamics of the magnetic black string are then discussed and it is shown that the locally stable bubble is the end point of a phase transition for an appropriate range of black string parameters.Comment: 5 pages, 1 figure. v3: references and stringy discussion added, v4: introduction expanded. Minor comments throughout. Accepted for publication in PL

Nonlinear programming model of a wastewater treatment system: Sensitivity analysis and a robustness constraint

A method for sensitivity analysis in nonlinear programming is described and then illustrated using a least-cost model of a secondary wastewater treatment system. A sensitivity equation approach is used to calculate normalized sensitivity coefficients, which approximate the percent changes in model variables and objective function due to a small parameter variation. Design changes predicted by the sensitivity coefficients are confirmed by a perturbation analysis of the optimal solution. Sensitivity concepts are used to develop a robustness measure which is incorporated into the constraint set of the nonlinear model. Robustness is narrowly defined as the ability of a model solution to maintain a level of performance that meets the system design criteria even if the actual values of model parameters are not exactly the same as the values assumed for design. A gradient optimization procedure is used to examine the tradeoff between total cost and the robustness measure. A preliminary analysis shows that the trends in robust wastewater treatment plant design are in direct conflict with the optimal decisions obtained when minimizing cost without a constraint on robustness but are in agreement with those designs observed to work in practice. The robustness constraint method presented should be applicable to other optimization models of water resources systems.U.S. Department of the InteriorU.S. Geological SurveyOpe

Higher Dimensional Dilaton Black Holes with Cosmological Constant

The metric of a higher-dimensional dilaton black hole in the presence of a cosmological constant is constructed. It is found that the cosmological constant is coupled to the dilaton in a non-trivial way. The dilaton potential with respect to the cosmological constant consists of three Liouville-type potentials.Comment: 8 pages,to appear in Phys. Lett.

Enzyme replacement therapy with taliglucerase alfa: 36-month safety and efficacy results in adult patients with Gaucher disease previously treated with imiglucerase.

Taliglucerase alfa is the first available plant cell-expressed human recombinant therapeutic protein. It is indicated for treatment of patients with type 1 Gaucher disease (GD) in adult and pediatric patients in several countries. Study PB-06-002 examined the safety and efficacy of taliglucerase alfa for 9 months in patients who previously received imiglucerase. The results of adult patients from Study PB-06-002 who continued receiving taliglucerase alfa in extension Study PB-06-003 for up to 36 months are reported here. Eighteen patients received at least one dose of taliglucerase alfa in Study PB-06-003; 10 patients completed 36 total months of therapy, and four patients who transitioned to commercial drug completed 30-33 months of treatment. In patients who completed 36 total months of treatment, mean percent (±standard error) changes from baseline/time of switch to taliglucerase alfa to 36 months were as follows: hemoglobin concentration, -1.0% (±1.9%; n = 10); platelet count, +9.3% (±9.8%; n = 10); spleen volume measured in multiples of normal (MN), -19.8% (±9.9%; n = 7); liver volume measured in MN, +0.9% (±5.4%; n = 8); chitotriosidase activity, -51.5% (±8.1%; n = 10); and CCL18 concentration, -36.5 (±8.0%; n = 10). Four patients developed antidrug antibodies, including one with evidence of neutralizing activity in vitro. All treatment-related adverse events were mild or moderate and transient. The 36-month results of switching from imiglucerase to taliglucerase alfa treatment in adults with GD provide further data on the clinical safety and efficacy of taliglucerase alfa beyond the initial 9 months of the original study. www.clinicaltrials.gov identifier NCT00705939. Am. J. Hematol. 91:661-665, 2016. © 2016 Wiley Periodicals, Inc

Quantum Fermion Hair

It is shown that the Dirac operator in the background of a magnetic %Reissner-Nordstr\"om black hole and a Euclidean vortex possesses normalizable zero modes in theories containing superconducting cosmic strings. One consequence of these zero modes is the presence of a fermion condensate around magnetically charged black holes which violates global quantum numbers.Comment: 16pp (harvmac (l)) and 2 figs.(not included

When Black Holes Meet Kaluza-Klein Bubbles

We explore the physical consequences of a recently discovered class of exact solutions to five dimensional Kaluza-Klein theory. We find a number of surprising features including: (1) In the presence of a Kaluza-Klein bubble, there are arbitrarily large black holes with topology S^3. (2) In the presence of a black hole or a black string, there are expanding bubbles (with de Sitter geometry) which never reach null infinity. (3) A bubble can hold two black holes of arbitrary size in static equilibrium. In particular, two large black holes can be close together without merging to form a single black hole.Comment: 23 pages, 5 figures, v2: few comments on stability modifie

Foundations for Forecasting: Defining Baseline Seismicity at Fuego Volcano, Guatemala

Accurate volcanic eruption forecasting is especially challenging at open vent volcanoes with persistent low levels of activity and relatively sparse permanent monitoring networks. We present a description of seismicity observed at Fuego volcano in Guatemala during January of 2012, a period representative of low-level, open-vent dynamics typical of the current eruptive period. We use this time to establish a baseline of activity from which to build more accurate forecasts. Seismicity consists of both harmonic and non-harmonic tremor, rockfalls, and a variety of signals associated with frequent small emissions from two vents. We categorize emissions into explosions and degassing events (each emitted from both vents); the seismic signatures from these two types of emissions are highly variable. We propose that both vents partially to fully seal between explosions. This model allows for the two types of emissions and accommodates the variety of seismic waveforms we recorded. In addition, there are many small discrete events not linked to eruptions that we examine in detail here. Of these events, 183 are classified into 5 families of repeating, pulse-like long period (0.5–5 Hz) events. Using arrival times from the 5 families and other high-quality events recorded on a temporary, nine-station network on the edifice of Fuego, we compute a 1-D velocity model and use it to locate earthquakes. The waveforms and shallow locations of the repeating families suggest that they are likely produced by rapid increases in gas pressure within a crack very near the surface, possibly within a sealed or partially sealed conduit. The framework from this study is a short but instrument intense observation period, activity description, seismic event detection, velocity modeling, and repose period analysis. This framework can act as a template for augmenting monitoring efforts at other under-studied volcanoes. Even relatively limited studies can at a minimum aid in drawing parallels between volcanic systems and improve comparisons

Instantaneous interaction in massive gravity

In general relativity, the instantaneous contributions to the gravitational potentials cancel each other in observable, leaving the theory free of physical instantaneous interactions. In models where these subtle cancellations are spoiled by the presence of fields that break Lorentz invariance, physical instantaneous interactions are possible. Such interactions are studied for a model of Lorentz- violating massive gravity

Nonexistence of marginally trapped surfaces and geons in 2+1 gravity

We use existence results for Jang's equation and marginally outer trapped surfaces (MOTSs) in 2+1 gravity to obtain nonexistence of geons in 2+1 gravity. In particular, our results show that any 2+1 initial data set, which obeys the dominant energy condition with cosmological constant \Lambda \geq 0 and which satisfies a mild asymptotic condition, must have trivial topology. Moreover, any data set obeying these conditions cannot contain a MOTS. The asymptotic condition involves a cutoff at a finite boundary at which a null mean convexity condition is assumed to hold; this null mean convexity condition is satisfied by all the standard asymptotic boundary conditions. The results presented here strengthen various aspects of previous related results in the literature. These results not only have implications for classical 2+1 gravity but also apply to quantum 2+1 gravity when formulated using Witten's solution space quantization.Comment: v3: Elements from the original two proofs of the main result have been combined to give a single proof, thereby circumventing an issue with the second proof associated with potential blow-ups of solutions to Jang's equation. To appear in Commun. Math. Phy

New instability for rotating black branes and strings

The evolution of small perturbations around rotating black branes and strings, which are low energy solutions of string theory, are investigated. For simplicity, we concentrate on the Kerr solution times transverse flat extra dimensions, possibly compactified, but one can also treat other branes composed of any rotating black hole and extra transverse dimensions, as well as analogue black hole models and rotating bodies in fluid mechanics systems. It is shown that such a rotating black brane is unstable against any massless (scalar, vectorial, tensorial or other) field perturbation for a wide range of wavelengths and frequencies in the transverse dimensions. Since it holds for any massless field it can be considered, in this sense, a stronger instability than the one studied by Gregory and Laflamme. Accordingly, it has also a totally different physical origin. The perturbations can be stabilized if the extra dimensions are compactified to a length smaller than the minimum wavelength for which the instability settles in, resembling in this connection the Gregory-Laflamme case. Likewise, this instability will have no effect for astrophysical black holes. However, in the large extra dimensions scenario, where TeV scale black holes can be produced, this instability should be important. It seems plausible that the endpoint of this instability is a static, or very slowly rotating, black brane and some outgoing radiation at infinity.Comment: 4 pages, ReVTeX4. v2: minor improvement