Bounds and algorithms for the K-Bessel function of imaginary order

AbstractUsing the paths of steepest descent, we prove precise bounds with numerical implied constants for the modified Bessel function${K}_{ir} (x)$of imaginary order and its first two derivatives with respect to the order. We also prove precise asymptotic bounds on more general (mixed) derivatives without working out numerical implied constants. Moreover, we present an absolutely and rapidly convergent series for the computation of${K}_{ir} (x)$and its derivatives, as well as a formula based on Fourier interpolation for computing with many values of$r$. Finally, we have implemented a subset of these features in a software library for fast and rigorous computation of${K}_{ir} (x)$.</jats:p

Collectors of Rhodiola species on the Sichuan-Tibetan and Sichuan-Shaanxi borders

Medicinal Rhodiola species, including Rhodiola rosea L. and Rhodiola crenulata (Hook.f. & Thomson) H.Ohba, have been widely used as traditional herbal medicines with numerous claims for their therapeutic effects. Faced with resource depletion, environment destruction and higher demand, R. rosea and R. crenulata are becoming endangered, making them economically even more valuable, but also increasing the risk of adulteration and low quality - and raising awareness for the role of often unlicensed collectors and middlemen. Although R. rosea is the most well known in Europe, R. crenulata is the recognised species in China. On the border of Sichuan and Tibet, members of the Yi minority collect R. crenulata in order to sell it to the “traditional” Chinese medicine market. Collection of this medicinal herb represents about one third of the annual income for the Yi. Three times a year they climb up to 5,000 metres in search of the plants. As it is stripped out, the Yi have to travel to more and more inhospitable places to ensure its supply. At Taibai mountain along the border of Sichuan and Shaanxi, the same medicinal plant, hongjingtian in Chinese, is growing in the wild, too. Yet, in a socioeconomic context, collectors do not have a particular ethnic background such as Yi, Tibetan or Han collectors. Here, the collectors are various unlicensed providers-cum-prescribers 'caoyi'. (The term does not mean herb-physician, as one might assume from terms such as caoyao (herbals). It means unofficial or not following the scholarly standard.) Using neither an ethnic identity nor the general botanical terms in Latin, they claim Daoism and terroir of their mountain as a sign of good quality ‘Taibai hongjingtian’. There appears to be no strategy in place to protect the species across all those socioeconomic, ethnic and provincial boundaries, and without some intervention it is likely that R. crenulata will eventually become so rare that it can no longer be collected in the current quantities. This will have consequences both for the livelihoods of the Yi and of various Caoyi, and also for the conservation of R. Crenulata and it’s sustainability

In sickness and in health? Comorbidity in older couples

We investigate the nature and origin of comorbidity, defined as the tendency of members of marital couples to display correlated patterns of ill-health in later life. In the absence of long-term prospective data on couples, we use long-range recall data from the pan-European SHARELife survey and estimate a latent variable model of the health states of marital partners in childhood, early adulthood and late adulthood. We find strong persistence in health states and a strong comorbidity correlation, attributable almost equally to homogamy in relation to early health and common factors operating within marriage

Probability Distributions of Random Electromagnetic Fields in the Presence of a Semi-Infinite Isotropic Medium

Using a TE/TM decomposition for an angular plane-wave spectrum of free random electromagnetic waves and matched boundary conditions, we derive the probability density function for the energy density of the vector electric field in the presence of a semi-infinite isotropic medium. The theoretical analysis is illustrated with calculations and results for good electric conductors and for a lossless dielectric half-space. The influence of the permittivity and conductivity on the intensity, random polarization, statistical distribution and standard deviation of the field is investigated, both for incident plus reflected fields and for refracted fields. External refraction is found to result in compression of the fluctuations of the random field.Comment: 23 pages, 11 figures, accepted for publication in Radio Scienc

Sexual orientation health inequality: Evidence from Understanding Society , the UK Longitudinal Household Study

Few studies from the United Kingdom have fully investigated inequalities between members of different sexual minority groups and heterosexuals over range of health outcomes. Using data from over 40,000 individuals, this study explores the health inequalities of sexual minority UK adults. We include respondents who identify as other and those who prefer not to say (PNS). Data come from wave three (2011–2012) of the nationally-representative Understanding Society, the UK Household Longitudinal Study. Sexual orientation was asked in the self-completion portion of the study. Markers of health include physical and mental functioning, minor psychological distress, self-rated health, substance use and disability. Multiple linear and logistic regression analyses tested for differences in markers of health between sexual orientation groups. Overall, heterosexual respondents had the best health while bisexual respondents had the worst. Gay and lesbian respondents reported poorer health than heterosexuals, specifically with regards to mental functioning, distress and illness status. The other and PNS respondents were most similar to each other and generally experienced fewer health inequalities than gay and lesbian respondents; they were less likely to use tobacco or alcohol. In sum, sexual minorities experience health inequality. The inclusion of other and PNS respondents has not been done in other studies and shows that while they may be healthier than gay/lesbian and bisexual respondents they still experiences poorer health than heterosexuals. Health promotion interventions are needed for these other and PNS individuals, who might not participate in interventions targeted toward known sexual minority groups

Forecasting time series by means of evolutionary algorithms

Proceeding of: 8th International Conference in Parallel Problem Solving from Nature - PPSN VIII , Birmingham, UK, September 18-22, 2004.The time series forecast is a very complex problem, consisting in predicting the behaviour of a data series with only the information of the previous sequence. There is many physical and artificial phenomenon that can be described by time series. The prediction of such phenomenon could be very complex. For instance, in the case of tide forecast, unusually high tides, or sea surges, result from a combination of chaotic climatic elements in conjunction with the more normal, periodic, tidal systems associated with a particular area. Too much variables influence the behaviour of the water level. Our problem is not only to find prediction rules, we also need to discard the noise and select the representative data. Our objective is to generate a set of prediction rules. There are many methods tying to achieve good predictions. In most of the cases this methods look for general rules that are able to predict the whole series. The problem is that usually the time series has local behaviours that dont allow a good level of prediction when using general rules. In this work we present a method for finding local rules able to predict only some zones of the series but achieving better level prediction. This method is based on the evolution of set of rules genetically codified, and following the Michigan approach. For evaluating the proposal, two different domains have been used: an artificial domain widely use in the bibliography (Mackey-Glass series) and a time series corresponding to a natural phenomenon, the water level in Venice Lagoon.Investigation supported by the Spanish Ministry of Science and Technology through the TRACER project under contract TIC2002-04498-C05-

Performing public credit at the eighteenth-century Bank of England

Much is known about the negotiation of personal credit relationships during the eighteenth century. It has been noted how direct contact and observation allowed individuals to assess the creditworthiness of those with whom they had financial connections and to whom they might lend money. Much less is known about one of the most important credit relationships of the long eighteenth century: that between the state and its creditors. This article shows that investors could experience the performance of public credit at the Bank of England. By 1760 the Bank was the manager of nearly three-quarters of the state's debt and housed the main secondary market in that debt. Thus, it provided a place for public creditors, both current and potential, to attend and scrutinize the performance of the state's promises. The article demonstrates how the Bank acted to embody public credit through its architecture, internal structures, and imagery and through the very visible actions of its clerks and the technologies that they used to record ownership and transfer of the national debt. The Bank of England, by those means, allowed creditors to interrogate the financial stability and reputation of the state in the same ways that they could interrogate the integrity of a private debtor.Peer reviewedFinal Accepted Versio

HOPS 383: An Outbursting Class 0 Protostar in Orion

We report the dramatic mid-infrared brightening between 2004 and 2006 of HOPS 383, a deeply embedded protostar adjacent to NGC 1977 in Orion. By 2008, the source became a factor of 35 brighter at 24 microns with a brightness increase also apparent at 4.5 microns. The outburst is also detected in the submillimeter by comparing APEX/SABOCA to SCUBA data, and a scattered-light nebula appeared in NEWFIRM K_s imaging. The post-outburst spectral energy distribution indicates a Class 0 source with a dense envelope and a luminosity between 6 and 14 L_sun. Post-outburst time-series mid- and far-infrared photometry shows no long-term fading and variability at the 18% level between 2009 and 2012. HOPS 383 is the first outbursting Class 0 object discovered, pointing to the importance of episodic accretion at early stages in the star formation process. Its dramatic rise and lack of fading over a six-year period hint that it may be similar to FU Ori outbursts, although the luminosity appears to be significantly smaller than the canonical luminosities of such objects.Comment: Accepted by ApJ Letters, 6 pages, 4 figures; v2 has an updated email address for the lead autho

Crystallographic snapshots of sulfur insertion by lipoyl synthase

Lipoyl synthase (LipA) catalyzes the insertion of two sulfur atoms at the unactivated C6 and C8 positions of a protein-bound octanoyl chain to produce the lipoyl cofactor. To activate its substrate for sulfur insertion, LipA uses a [4Fe-4S] cluster and S-adenosylmethionine (AdoMet) radical chemistry; the remainder of the reaction mechanism, especially the source of the sulfur, has been less clear. One controversial proposal involves the removal of sulfur from a second (auxiliary) [4Fe-4S] cluster on the enzyme, resulting in destruction of the cluster during each round of catalysis. Here, we present two high-resolution crystal structures of LipA from Mycobacterium tuberculosis: one in its resting state and one at an intermediate state during turnover. In the resting state, an auxiliary [4Fe-4S] cluster has an unusual serine ligation to one of the irons. After reaction with an octanoyllysine-containing 8-mer peptide substrate and 1 eq AdoMet, conditions that allow for the first sulfur insertion but not the second insertion, the serine ligand dissociates from the cluster, the iron ion is lost, and a sulfur atom that is still part of the cluster becomes covalently attached to C6 of the octanoyl substrate. This intermediate structure provides a clear picture of iron-sulfur cluster destruction in action, supporting the role of the auxiliary cluster as the sulfur source in the LipA reaction and describing a radical strategy for sulfur incorporation into completely unactivated substrates. Keywords: iron–sulfur cluster; radical SAM enzyme; lipoic acidNational Science Foundation (U.S.) (Grant MCB-0543833

A Comparative Study of the ReCell® Device and Autologous Spit-Thickness Meshed Skin Graft in the Treatment of Acute Burn Injuries.

Early excision and autografting are standard care for deeper burns. However, donor sites are a source of significant morbidity. To address this, the ReCell® Autologous Cell Harvesting Device (ReCell) was designed for use at the point-of-care to prepare a noncultured, autologous skin cell suspension (ASCS) capable of epidermal regeneration using minimal donor skin. A prospective study was conducted to evaluate the clinical performance of ReCell vs meshed split-thickness skin grafts (STSG, Control) for the treatment of deep partial-thickness burns. Effectiveness measures were assessed to 1 year for both ASCS and Control treatment sites and donor sites, including the incidence of healing, scarring, and pain. At 4 weeks, 98% of the ASCS-treated sites were healed compared with 100% of the Controls. Pain and assessments of scarring at the treatment sites were reported to be similar between groups. Significant differences were observed between ReCell and Control donor sites. The mean ReCell donor area was approximately 40 times smaller than that of the Control (P &lt; .0001), and after 1 week, significantly more ReCell donor sites were healed than Controls (P = .04). Over the first 16 weeks, patients reported significantly less pain at the ReCell donor sites compared with Controls (P ≤ .05 at each time point). Long-term patients reported higher satisfaction with ReCell donor site outcomes compared with the Controls. This study provides evidence that the treatment of deep partial-thickness burns with ASCS results in comparable healing, with significantly reduced donor site size and pain and improved appearance relative to STSG