Chaotic Inflation from Nonlinear Sigma Models in Supergravity

We present a common solution to the puzzles of the light Higgs or quark masses and the need for a shift symmetry and large field values in high scale chaotic inflation. One way to protect, for example, the Higgs from a large supersymmetric mass term is if it is the Nambu-Goldstone boson (NGB) of a nonlinear sigma model. However, it is well known that nonlinear sigma models (NLSMs) with nontrivial K\"ahler transformations are problematic to couple to supergravity. An additional field is necessary to make the K\"ahler potential of the NLSM invariant in supergravity. This field must have a shift symmetry --- making it a candidate for the inflaton (or axion). We give an explicit example of such a model for the coset space $SU(3)/SU(2) \times U(1)$, with the Higgs as the NGB, including breaking the inflaton's shift symmetry and producing a chaotic inflation potential. This construction can also be applied to other models, such as one based on $E_7/SO(10) \times U(1) \times U(1)$ which incorporates the first two generations of (light) quarks as the Nambu-Goldstone multiplets, and has an axion in addition to the inflaton. Along the way we clarify and connect previous work on understanding NLSMs in supergravity and the origin of the extra field (which is the inflaton here), including a connection to Witten-Bagger quantization. This framework has wide applications to model building; a light particle from a NLSM requires, in supergravity, exactly the structure for chaotic inflaton or an axion.Comment: 5 page

An approximation theory for the identification of nonlinear distributed parameter systems

An abstract approximation framework for the identification of nonlinear distributed parameter systems is developed. Inverse problems for nonlinear systems governed by strongly maximal monotone operators (satisfying a mild continuous dependence condition with respect to the unknown parameters to be identified) are treated. Convergence of Galerkin approximations and the corresponding solutions of finite dimensional approximating identification problems to a solution of the original finite dimensional identification problem is demonstrated using the theory of nonlinear evolution systems and a nonlinear analog of the Trotter-Kato approximation result for semigroups of bounded linear operators. The nonlinear theory developed here is shown to subsume an existing linear theory as a special case. It is also shown to be applicable to a broad class of nonlinear elliptic operators and the corresponding nonlinear parabolic partial differential equations to which they lead. An application of the theory to a quasilinear model for heat conduction or mass transfer is discussed

A comparison of the physiological consequences of head-loading and back-loading for African and European women

The aim is to quantify the physiological cost of head-load carriage and to examine the ‘free ride’ hypothesis for head-load carriage in groups of women differing in their experience of head-loading. Twenty-four Xhosa women [13 experienced head-loaders (EXP), 11 with no experience of head-loading (NON)] attempted to carry loads of up to 70% of body mass on both their heads and backs whilst walking on a treadmill at a self-selected walking speed. Expired air was collected throughout. In a second study nine women, members of the British Territorial Army, carried similar loads, again at a self-selected speed. Maximum load carried was greater for the back than the head (54.7 ± 15.1 vs. 40.8 ± 13.2% BM, P <0.0005). Considering study one, head-loading required a greater oxygen rate than back-loading (10.1 ± 2.6 vs. 8.8 ± 2.3 ml kg bodymass−1 min−1, P = 0.043, for loads 10–25% BM) regardless of previous head-loading experience (P = 0.333). Percentage changes in oxygen consumption associated with head-loading were greater than the proportional load added in both studies but were smaller than the added load for the lighter loads carried on the back in study 1. All other physiological variables were consistent with changes in oxygen consumption. The data provides no support for the ‘free ride’ hypothesis for head-loading although there is some evidence of energy saving mechanisms for back-loading at low speed/load combinations. Investigating the large individual variation in response may help in identifying combinations of factors that contribute to improved economy

Numerical studies of identification in nonlinear distributed parameter systems

An abstract approximation framework and convergence theory for the identification of first and second order nonlinear distributed parameter systems developed previously by the authors and reported on in detail elsewhere are summarized and discussed. The theory is based upon results for systems whose dynamics can be described by monotone operators in Hilbert space and an abstract approximation theorem for the resulting nonlinear evolution system. The application of the theory together with numerical evidence demonstrating the feasibility of the general approach are discussed in the context of the identification of a first order quasi-linear parabolic model for one dimensional heat conduction/mass transport and the identification of a nonlinear dissipation mechanism (i.e., damping) in a second order one dimensional wave equation. Computational and implementational considerations, in particular, with regard to supercomputing, are addressed

Fabrication of salt–hydrogel marbles and hollow-shell microcapsules by an aerosol gelation technique

We designed a new method for preparation of liquid marbles by using hydrophilic particles. Salt–hydrogel marbles were prepared by atomising droplets of hydrogel solution in a cold air column followed by rolling of the collected hydrogel microbeads in a bed of micrometre sized salt particles. Evaporation of the water from the resulting salt marbles with a hydrogel core yielded hollow-shell salt microcapsules. The method is not limited to hydrophilic particles and could potentially be also applied to particles of other materials, such as graphite, carbon black, silica and others. The structure and morphology of the salt–hydrogel marbles were analysed by SEM and their particle size distributions were measured. We also tested the dissolution times of the dried salt marbles and compared them with those of table salt samples under the same conditions. The high accessible surface area of the shell of salt microcrystals allows a faster initial release of salt from the hollow-shell salt capsules upon their dissolution in water than from the same amount of table salt. The results suggest that such hollow-shell particles could find applications as a table salt substitute in dry food products and salt seasoning formulations with reduced salt content without the loss of saltiness

Međulaboratorijska provjera kakvoće mjerenja aktivnosti serumske kolinesteraze

The measurement of cholinesterase activity is an important function of a clinical laboratory. Participation in appropriate quality assurance schemes is essential in ensuring a high analytical standard. Samples of human serum were distributed to thirty-five laboratories for the measurement of cholinesterase activity. Because of methodological differences between the participants, findings of each laboratory were compared either by the use of duplicate samples or by analysis of six mixtures of two samples, one having a high and one a low activity. Of 4,964 distributed samples 95% were analysed and findings reported in 596 reports. Thirty-four percent of all reports were considered very good (less than 5% within-run error) and 38% less than satisfactory (within-run error over 10%). Access to a proficiency programme such as this enables laboratories to evaluate the quality of their analytical service.Mjerenje aktivnosti serumske kolinesteraze važna je zadaća kliničkih laboratorija. Smanjena aktivnost kolinesteraze upućuje na smanjenje funkcije jetre ili može biti znak i mjera stupnja izloženosti organskofosfornim spojevima i karbamatima. Serumska kolinesteraza (butirilkolinesteraza) razgrađuje kratkodjelujuće mišićne relaksanse kao što je sukcinilkolin, pa je prije njihove primjene pacijentima potrebno provjeriti aktivnost toga enzima u serumu. Kako bi se osigurao visoki analitički standard mjerenja, poželjno je da laboratorij sudjeluje u programima kontrole kakvoće mjerenja. Tijekom četiri i pol godine proveden je program provjere osposobljenosti laboratorija za mjerenje aktivnosti kolinesteraze u serumu. U programu je sudjelovalo u prosjeku trideset pet laboratorija. Svakom laboratoriju poslano je u 18 navrata po 8 uzoraka ljudskog seruma. Laboratoriji su mjerili aktivnost metodom koja je već bila uvedena u dotičnom laboratoriju. U prosjeku oko 16 laboratorija rabilo je benzoilkolin kao supstrat za mjerenje aktivnosti kolinesteraze, a ostali laboratoriji rabili su tiokolinske supstrate. Nepreciznost mjerenja svakog laboratorija provjeravana je usporedbom uzoraka u duplikatu i analizom rezultata mjerenja 6 uzoraka, koji su bili priređeni miješanjem u određenom omjeru jednog uzorka velike i jednog uzorka male ili nikakve aktivnosti: omjere miješanja znao je samo organizator. Od 4964 razaslana uzorka, 95% ih je bilo analizirano i laboratoriji su poslali svoje nalaze organizatoru. Prilikom idućeg slanja uzoraka sudionici su dobili rezultate svoje analize, kao i rezultate drugih laboratorija. Organizator je ukupno primio 596 izvještaja s nalazima mjerenja aktivnosti uzoraka. U oko 34% izvještaja rezultati su dobiveni s nepreciznošću mjerenja manjom od 5%, dok je u 38% izvještaja bilo barem jedno mjerenje određeno s nepreciznošću većom od 10%. Mjerenja obavljena s benzoilkolinom kao supstratom bila su nepreciznija nego ona s tiokolinskim supstratom, ali razlika u nepreciznosti nije bila dovoljno velika da bi se laboratorijima savjetovalo da promijene supstrat u svojim mjerenjima. Na osnovi iscrpne analize rezultata koju su redovito dobivali, sudionici su mogli procijeniti svoju osposobljenost za mjerenje aktivnosti toga enzima i, ako je bilo potrebno, poboljšati svoja mjerenja. U drugom dijelu programa povećao se broj izvještaja s nalazima veće preciznosti

Detection of SUSY Signals in Stau Neutralino Co-annihilation Region at the LHC

We study the prospects of detecting the signal in the stau neutralino co-annihilation region at the LHC using tau leptons. The co-annihilation signal is characterized by the stau and neutralino mass difference (dM) to be 5-15 GeV to be consistent with the WMAP measurement of the cold dark matter relic density as well as all other experimental bounds within the minimal supergravity model. Focusing on tau's from neutralino_2 --> tau stau --> tau tau neutralino_1 decays in gluino and squark production, we consider inclusive MET+jet+3tau production, with two tau's above a high E_T threshold and a third tau above a lower threshold. Two observables, the number of opposite-signed tau pairs minus the number of like-signed tau pairs and the peak position of the di-tau invariant mass distribution, allow for the simultaneous determination of dM and M_gluino. For dM = 9 GeV and M_gluino = 850 GeV with 30 fb^-1 of data, we can measure dM to 15% and M_gluino to 6%.Comment: 4 pages LaTex, 3 figures. To appear in Proceedings of SUSY06, the 14th International Conference on Supersymmetry and the Unification of Fundamental Interactions, UC Irvine, California, 12-17 June 2006. A typo in a reference is correcte

Estimating Price Premiums for Breads Marketed as “Low-Carbohydrate Breadsâ€

Retail data are used in a hedonic pricing framework to estimate the premium paid for the “low-carbohydrate†attribute and other attributes of bread at grocery and non-grocery stores in a regional market. Results show that consumer willingness to pay is influenced by the “low-carbohydrate†attribute as well as by sugar, fiber, and fat content; serving size; and size of loaf. Implicit price premiums vary significantly by retail location. However, price differentials may be compounded by the absence of an acceptable definition for low-carbohydrate foods.Demand and Price Analysis, Marketing,

Temperature dependence of the radiative recombination coefficient in crystalline silicon from spectral photoluminescence

The radiative recombination coefficient B(T) in crystalline silicon is determined for the temperature range 90–363 K, and in particular from 270 to 350 K with an interval of 10 K, where only sparse data are available at present. The band-band absorption coefficient established recently by Nguyen et al. [J. Appl. Phys. 115, 043710 (2014)] via photoluminescence spectrum measurements is employed to compute the values of B(T) at various temperatures. The results agree very well with literature data from Trupke et al. [J. Appl. Phys. 94, 4930 (2003).] We present a polynomial parameterization describing the temperature dependence of the product of B(T) and the square of the intrinsic carrier density. We also find that B(T) saturates at a near constant value at room temperature and above for silicon samples with relatively low free carrier densities