Ultralong-range Rydberg molecules

We review ultralong-range Rydberg molecules (ULRM), which are bound states between a Rydberg atom and one or more ground-state atoms with bond lengths on the order of thousands of Bohr radii. The binding originates from multiple electron-atom scattering and leads to exotic oscillatory potential energy surfaces that reflect the probability density of the Rydberg electron. This unconventional binding mechanism opens fascinating possibilities to tune molecular properties via weak external fields, to study spin-resolved low-energy electron-atom scattering as well as to control and to probe interatomic forces in few- and many-body systems. Here, we provide an overview on recent theoretical and experimental progress in the field with an emphasis on polyatomic ULRMs, field control and spin interactions.Comment: 14 pages, 8 figure

Astrometric Positions and Proper Motions of 19 Radio Stars

We have used the Very Large Array, linked with the Pie Town Very Long Baseline Array antenna, to determine astrometric positions of 19 radio stars in the International Celestial Reference Frame (ICRF). The positions of these stars were directly linked to the positions of distant quasars through phase referencing observations. The positions of the ICRF quasars are known to 0.25 mas, thus providing an absolute reference at the angular resolution of our radio observations. Average values for the errors in our derived positions for all sources were 13 mas and 16 mas in R.A. and declination respectively, with accuracies approaching 1-2 mas for some of the stars observed. Differences between the ICRF positions of the 38 quasars, and those measured from our observations showed no systematic offsets, with mean values of -0.3 mas in R.A. and -1.0 mas in declination. Standard deviations of the quasar position differences of 17 mas and 11 mas in R.A. and declination respectively, are consistent with the mean position errors determined for the stars. Our measured positions were combined with previous Very Large Array measurements taken from 1978-1995 to determine the proper motions of 15 of the stars in our list. With mean errors of approximately 1.6 mas/yr, the accuracies of our proper motions approach those derived from Hipparcos, and for a few of the stars in our program, are better than the Hipparcos values. Comparing the positions of our radio stars with the Hipparcos catalog, we find that at the epoch of our observations, the two frames are aligned to within formal errors of approximately 3 mas. This result confirms that the Hipparcos frame is inertial at the expected level.Comment: 20 pages, 9 figures Accepted by the Astronomical Journal, 2003 March 1

VSOP and Ground-based VLBI Imaging of the TeV Blazar Markarian 421 at Multiple Epochs

We present thirty VLBI images of the TeV blazar Markarian 421 (1101+384) at fifteen epochs spanning the time range from 1994 to 1997, and at six different frequencies from 2.3 to 43 GHz. The imaged observations include a high-resolution 5 GHz VLBI Space Observatory Programme (VSOP) observation with the HALCA satellite on 1997 November 14; full-track VLBA observations from 1994 April, 1996 November, and 1997 May at frequencies between 5 and 43 GHz; six epochs of VLBA snapshot observations at frequencies between 2 and 15 GHz from Radio Reference Frame studies; and five geodetic VLBI observations at 2 and 8 GHz from the archive of the Washington VLBI Correlator Facility located at the U.S. Naval Observatory. The dense time coverage of the images allows us to unambiguously track components in the parsec-scale jet over the observed time range. We measure the speeds of three inner jet components located between 0.5 and 5 mas from the core (0.3 to 3 pc projected linear distance) to be 0.19 +/- 0.27, 0.30 +/- 0.07, and -0.07 +/- 0.07 c (H_{0}=65 km s^{-1} Mpc^{-1}). If the sole 43 GHz image is excluded, all measured speeds are consistent with no motion. These speeds differ from tentative superluminal speeds measured by Zhang & B\aa\aa th from three epochs of data from the early 1980's. Possible interpretations of these subluminal speeds in terms of the high Doppler factor demanded by the TeV variability of this source are discussed.Comment: 18 pages, including 7 figures, emulateapj.sty, accepted by The Astrophysical Journal; modified text describing Radio Reference Frame observation

Reduced dose of subcutaneous cladribine induces identical response rates but decreased toxicity in pretreated chronic lymphocytic leukaemia

Purpose To study the efficacy and the safety of cladribine (2-chlorodeoxyadenosine, 2-CDA) administered as 24-hour infusions or as subcutaneous bolus injections at two different doses to patients with relapsing or refractory chronic lymphocytic leukaemia (CLL). Patients and methods In this non randomised 2-cohort study, 20 patients with pretreated CLL received cladribine at a dose of 0.7 mg/kg/cycle as continuous i.v. infusions over seven days (group 1) and 35 patients were treated at a reduced dose of 0.5 mg/kg/cycle given as s.c. bolus injections for five days (group 2). After two cycles of four week duration, response was assessed. In the case of progressive disease, therapy was discontinued, otherwise a maximum of four additional cycles were administered until best response. Results A total of 130 cycles were administered (group 1: 41, group 2: 89). Patient characteristics in both groups were comparable. The median dose intensities were 0.172 mg/kg per week and 0.123 mg/kg per week for groups 1 and 2, respectively (P ≤ 0.0001). The overall response rate for all 55 patients was 38% (95% confidence interval (95% CI): 25%-52%), with 5% CR and 33% PR. Response was similar in both patient groups (35% in group 1, 40% in group 2). No association between cladribine dose intensity and response rate was found, and there was no difference between patients relapsing after or refractory to previous therapies (11 of 24 vs. 10 of 31). Median remission duration was six months in both groups. Toxicity, in particular infections (all WHO grades, 34% in group 1 versus 7% in group 2) and myelosuppression (grade 1-4 neutropenia, 72% versus 41% of cladribine cycles) were statistically significantly more frequent in group 1. Conclusion Cladribine is active in heavily pretreated patients with chronic lymphocytic leukaemias. Dose reduction by 29% led to similar response and remission duration, but to a significant decrease of myelotoxicity and risk of infection. Cladribine administered as s.c. bolus injections at 0.5 mg/kg per cycle is safe and this dose level should not be exceeded in this patient populatio

Patient-reported outcome measures obtained via E-Health tools ease the assessment burden and encourage patient participation in cancer care (PaCC Study)

Patient-reported outcome measures obtained via E-Health tools ease the assessment burden and encourage patient participation in cancer care (PaCC Study) BACKGROUND: E-health based patient-reported outcome measures (PROMs) have the potential to automate early identification of both nutrition status and distress status in cancer patients while facilitating treatment and encouraging patient participation. This cross-sectional study assessed the acceptability, accuracy, and clinical utility of PROMs collected via E-Health tools among patients undergoing treatment for stomach, colorectal, and pancreatic tumors. RESULTS: Eight-nine percent mostly, or completely, agreed that PROMs via tablets should be integrated in routine clinical care. Men were significantly more likely to require help completing the questionnaires than women (inv.OR= 0.51, 95% CI=(0.27, 0.95), p = 0.035). The level of help needed increased by 3% with each 1-year increase in age (inv. OR=1.03, 95% CI=(1.01, 1.06), p = 0.013). On average, a patient tended to declare weight which was 0.84 kg inferior to their true weight (Bland and Altman 95 % CI=(-3.9, 5.6); SD: 2.41) and a height which was 0.95 cm superior to their true height (Bland and Altman 95 % CI=(-5, 3.1); SD 2.08). Patient-reported nutrition status was significantly associated with the professionally generated assessment (95% CI=(2.27, 4.15), p < 0.001). As nutrition status declined, the distress score increased (95%CI=(0.88, 1.68), p < 0.001). Of the patients, 48.8% who were both distressed and malnourished requested supportive care to address their problems. CONCLUSION: Patient-reported assessments utilizing E-health tools are an accurate and efficient method to encourage patient participation in cancer care while simultaneously ensuring that regular assessment of psycho-social and nutritional aspects of care are efficiently integrated in the daily clinical routine

Multi-frequency VLBA observations of compact sources from the Peacock & Wall catalogue

VLBA observations are presented for 6 compact radio sources selected from the Peacock & Wall catalogue. From the new morphological and spectral information 2 objects that in the Peacock and Wall catalogue are flat spectrum (alpha < 0.5) sources, appear to be double sided objects with linear sizes of the order of one kpc. Three are core-jet sources and the last one is still an ``enigmatic'' object. These data complete the sample of small double compact sources in the Peacock & Wall catalogue and the complete list is given.Comment: 11 pages, 14 figures, aa.cls Accepted by A&

Management and Organization Review Special Issue "Social Networks The Dark and Bright Sides of Informal Networks'

Research on the mechanisms of organizing and managing via interpersonal relations has a rich history in the management and organization-oriented literature. So far, however, the informal dimension of managing and organizing by drawing on informal networks in an international context has received comparably less attention. Recent research has pointed out that social capital and network theories have largely been developed by Western scholars based on circumstances and social structures that are typical of Western societies. Thus, current theory takes into account to a lesser extent their character and nature and the way in which informal ties and networks are formed in other parts of the world (Ledeneva, 2018; Li, 2007b; Qi, 2013; Sato, 2010). Besides the growing body of literature concerned with informal ties and networks in emerging and transitioning countries, for example guanxi (China), blat/svyazi (Russia), and wasta (Arab World), a trend for analyzing pervasive informal networks in advanced and industrialized economies, such as yongo (Korea), has arisen. While insights from the latter research stream indicate that informal networks persist, the results generated in both research streams will help in developing the extant informal network theories further

Ceftriaxone-Resistant Salmonella Infection Acquired by a Child from Cattle

Background The emergence of resistance to antimicrobial agents within the salmonellae is a worldwide problem that has been associated with the use of antibiotics in livestock. Resistance to ceftriaxone and the fluoroquinolones, which are used to treat invasive salmonella infections, is rare in the United States. We analyzed the molecular characteristics of a ceftriaxone-resistant strain of Salmonella enterica serotype typhimurium isolated from a 12-year-old boy with fever, abdominal pain, and diarrhea. Methods We used pulsed-field gel electrophoresis and analysis of plasmids and β-lactamases to compare the ceftriaxone-resistant S. enterica serotype typhimurium from the child with four isolates of this strain obtained from cattle during a local outbreak of salmonellosis. Results The ceftriaxone-resistant isolate from the child was indistinguishable from one of the isolates from cattle, which was also resistant to ceftriaxone. Both ceftriaxone-resistant isolates were resistant to 13 antimicrobial agents; all but one of the resistance determinants were on a conjugative plasmid of 160 kb that encoded the functional group 1 β-lactamase CMY-2. Both ceftriaxone-resistant isolates were closely related to the three other salmonella isolates obtained from cattle, all of which were susceptible to ceftriaxone. Conclusions This study provides additional evidence that antibiotic-resistant strains of salmonella in the United States evolve primarily in livestock. Resistance to ceftriaxone, the drug of choice for invasive salmonella disease, is a public health concern, especially with respect to children, since fluoroquinolones, which can also be used to treat this disease, are not approved for use in children