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The standard alpha-disc model predicts an anti-correlation between the density of the inner accretion disc and the black hole mass times square of the accretion rate, as seen in higher mass ($M_{\rm BH}>10^{6} M_{\odot}$) active galactic nuclei (AGNs). In this work, we test the predictions of the alpha-disc model and study the properties of the inner accretion flow for the low-mass end ($M_{\rm BH}\approx 10^{5-6}M_{\odot}$) of AGNs. We utilize a new high-density disc reflection model where the density parameter varies from $n_{\rm e}=10^{15}$ to $10^{20}$ cm$^{-3}$ and apply it to the broadband X-ray (0.3-10 keV) spectra of the low-mass AGN sample. The sources span a wide range of Eddington fractions and are consistent with being sub-Eddington or near-Eddington. The X-ray spectra reveal a soft X-ray excess below $\sim 1.5$ keV which is well modeled by high-density reflection from an ionized accretion disc of density $n_{\rm e}\sim 10^{18}$ cm$^{-3}$ on average. The results suggest a radiation pressure-dominated disc with an average of 70% fraction of the disc power transferred to the corona, consistent with that observed in higher mass AGNs. We show that the disc density higher than $10^{15}$ cm$^{-3}$ can result from the radiation pressure compression when the disc surface does not hold a strong magnetic pressure gradient. We find tentative evidence for a drop in black hole spin at low-mass regimes., 20 pages, 10 figures, 6 tables. Accepted for publication in MNRAS

In this paper we use an RXTE library of spectral models from 10 black-hole and 9 pulsar X-ray binaries, as well as model spectra available in the literature from 13 extra-galactic Ultra-luminous X-ray sources (ULXs). We compute average bolometric corrections (BC=$\mathrm{L_{band}/L_{bol}}$) for our sample as a function of different accretion rates. We notice the same behaviour between black-hole and pulsars BCs only when ULX pulsars are included. These measurements provide a picture of the energetics of the accretion flow for an X-ray binary based solely on its observed luminosity in a given band. Moreover it can be a powerful tool in X-ray binary population synthesis models. Furthermore we calculate the X-ray (2-10 keV) to optical (V-band) flux ratios at different Eddington ratios for the black-hole X-ray binaries in our sample. This provides a metric of the maximum contribution of the disk to the optical emission of a binary system and better constraints on its nature (donor type etc). We find that the optical to X-ray flux ratio shows very little variation as a function of accretion rate, but testing for different disk geometries scenarios we find that the optical contribution of the disk increases as the $p$ value decreases ($T(r)\sim r^{-p}$). Moreover observational data are in agreement with a thicker disk scenario ($p, 16 pages, 6 figures, 14 tables, accepted for publication in MNRAS

The geometry of the accretion flow around stellar-mass black holes can change on timescales of days to months

We study the ac anomalous Hall conductivity $\sigma_{xy}(\omega)$ of a Weyl semimetal with broken time-reversal symmetry. Even in the absence of free carriers these materials exhibit a "universal" anomalous Hall response determined solely by the locations of the Weyl nodes. We show that the free carriers, which are generically present in an undoped Weyl semimetal, give an additional contribution to the ac Hall conductivity. We elucidate the physical mechanism of the effect and develop a microscopic theory of the free carrier contribution to $\sigma_{xy}(\omega)$. The latter can be expressed in terms of a small number of parameters (the electron velocity matrix, the Fermi energy $\mu$, and the "tilt" of the Weyl cone). The resulting $\sigma_{xy}(\omega)$ has resonant features at $\omega \sim 2 \mu$ which may be used to separate the free carrier response from the filled-band response using, for example, Kerr effect measurements. This may serve as diagnostic tool to characterize the doping of individual valleys., Comment: 4 pages, 4 figures

OBJECTIVE: To assess adequacy of reimbursement for childhood vaccinations in two rural regions in Colorado, the authors measured medical practice costs of providing childhood vaccinations and compared them with reimbursement. METHODS: A "time-motion" method was used to measure labor costs of providing vaccinations in 13 private and public practices. Practices reported non-labor costs. The authors determined reimbursement by record review. RESULTS: The average vaccine delivery cost per dose (excluding vaccine cost) ranged from $4.69 for community health centers to $5.60 for private practices. Average reimbursement exceeded average delivery costs for all vaccines and contributed to overhead in private practices. Average reimbursement was less than total cost (vaccine-delivery costs + overhead) in private practices for most vaccines in one region with significant managed care penetration. Reimbursement to public providers was less than the average vaccine delivery costs. CONCLUSIONS: Current reimbursement may not be adequate to induce private practices to provide childhood vaccinations, particularly in areas with substantial managed care penetration.

To identify barriers to enrollment into Colorado's Child Health Insurance Plan (CHP+) for non-Hispanic (NH), Hispanic (H), and uninsured families.Telephone survey of 1) random samples of families who requested an application but did not complete it (N = 273 NH, N = 159 H) and 2) families with uninsured children identified by random-digit-dial statewide surveys (N = 165).Major reasons for not enrolling included 1) got other insurance (NH 16.5%; H 27.2% P.01), 2) thought household income was too high to qualify (NH 21.0%; H 11.9% P =.01), and 3) paperwork (NH 13.4%; H 14.7%, P = NS). Of those who thought their income was too high (N = 76, 17.6%), 58.5% appeared eligible based on reported income. Of uninsured families, only 41.7% had heard of CHP+. Of those who had never applied, major remediable reasons included not knowing enough about the program (20.9%) and thinking household income was too high (9.3%).Effective marketing and education to increase awareness of CHP+ and ensure understanding of eligibility are critical to the success of the program.

To determine increases in immunization up-to-date (UTD) rates at a rural pediatric practice with the sequential addition of records from other sites in a 2-county region.UTD rates for children aged 3 months to 35 months (n = 876) were determined for the index practice and then recalculated after sequential addition of records from 1) the other private practice in the region, 2) 7 public primary care sites, and 3) 2 public health clinics in the region.Adding records from all sites increased documented UTD rates in the index practice from 49% to 64% at 3 months (N = 33, P = 0.025), 50% to 68% at 5 months (N = 38, P = 0.008), 28% to 45% at 7 months (N = 113, P.01), 29% to 54% at 12 months (N = 200, P.001), 11% to 35% at 19 months (N = 124, P.001), and 10% to 33% at 24 months (N = 368, P.001).Regional registries will be valuable tools for immunization delivery if there is an ongoing commitment to effective collection of current and historical immunization data.

Using a patient and clinician educational intervention, we successfully reduced antibiotic use for uncomplicated acute bronchitis. The impact of this intervention on patient satisfaction is not known.To evaluate whether a strategy for reducing antibiotic use in acute bronchitis affects satisfaction among adult patients.Telephone survey administered 1 to 4 weeks after an office visit for acute bronchitis.Two outpatient clinics belonging to a group-model HMO in the Denver, Colorado, metropolitan area. The intervention clinic had received a patient and office-based educational intervention that successfully reduced antibiotic prescribing for acute bronchitis during the previous winter. The control clinic received only the office-based materials, an intervention that did not reduce antibiotic prescribing.Overall satisfaction with the episode of care.Antibiotics were prescribed to 64% and 85% of survey respondents at the intervention (n = 102) and control clinics (n = 164), respectively (P0.001). Patient satisfaction with the visit did not differ between intervention and control clinics (69% of intervention and 63% of control clinic patients reported very good or excellent satisfaction, P0.2). After adjustment for patient age, sex, duration of illness before the visit, reason for visit, and clinician specialty, there was no difference between intervention and control clinics in the proportion of patients reporting very good or excellent satisfaction (adjusted relative risk for high satisfaction at the intervention clinic, 1.1 [95% CI, 0.81 to 1.3]).A patient- and clinician-oriented educational intervention that reduces antibiotic treatment of adults with uncomplicated acute bronchitis does not appear to reduce satisfaction with care.

Previous studies examining differences in the quality of care between capitated and fee-for-service payment systems have focused on the care delivered in a single setting. No study to date has compared outcomes over an entire episode of care delivered across multiple settings.To compare outcomes of care for patients receiving institutional rehabilitation for hip fracture in fee-for-service and group/staff HMO delivery systems.One-year prospective inception cohort.Six hospital-based, integrated care systems paid on a traditional fee-for-service model and five group/staff HMOs (paid fixed capitation rate by Medicare). The 11 delivery systems were selected because of their commitment to geriatric rehabilitation.196 fee-for-service and 140 group/staff HMO patients with acute hip fracture were identified on admission to inpatient rehabilitation.Four primary outcomes--recovery of activities of daily living, improvement in ambulation, return to community living, and mortality--were measured at 3, 6, 9, and 12 months. Service utilization was assessed in the acute-care hospital setting, rehabilitation setting, and at each 3-month follow-up interval. Risk adjustment was performed by using multiple and logistic regression.Overall, no differences were found between patients in group/staff HMOs and fee-for-service patients. Group/staff HMO patients experienced improved functional recovery at 6 months (P0.01) and improved ambulation at 12 months (P = 0.05) compared with fee-for-service patients, although these were isolated findings. With regard to utilization, group/staff HMO delivery systems used physician services less intensively and substituted less-skilled allied health personnel.Compared with fee-for-service delivery systems, with a similar commitment to excellence in geriatric rehabilitation, group/staff HMOs can achieve equivalent outcomes in older patients recovering from hip fracture with less-intense service utilization.

Antibiotic use is associated with increased rates of antibiotic-resistant organisms. A previous study has shown that colds, upper respiratory tract infections, and bronchitis account for nearly one third of all antibiotic prescribing by ambulatory care physicians. How frequently antibiotics are prescribed for these conditions and for and by whom is not known.To measure antibiotic prescription rates and to identify predictors of antibiotic use for adults diagnosed as having colds, upper respiratory tract infections, and bronchitis in the United States.Sample survey of practicing physicians participating in the National Ambulatory Medical Care Survey, 1992.Office-based physician practices.Physicians (n=1529) completing patient record forms for adult office visits (n=28787).Antibiotic prescriptions for colds, upper respiratory tract infections, and bronchitis.Office visits for colds, upper respiratory tract infections, and bronchitis resulted in approximately 12 million antibiotic prescriptions, accounting for 21% of all antibiotic prescriptions to adults in 1992. A total of 51 % of patients diagnosed as having colds, 52% of patients diagnosed as having upper respiratory tract infections, and 66% of patients diagnosed as having bronchitis were treated with antibiotics. Female sex (odds ratio [OR], 1.65; 95% confidence interval [CI], 1.05-2.62) and rural practice location (OR, 2.25; 95% CI, 1.33-3.80) were associated with greater antibiotic prescription rates, whereas black race (OR, 0.44; 95% CI, 0.21-0.93) was associated with lower antibiotic prescription rates. Patient age, Hispanic ethnicity, geographic region, physician specialty, and payment sources were not associated with antibiotic prescription rates in the bivariate analysis. Multivariate logistic regression analysis identified only rural practice location (adjusted OR, 2.58; 95% CI, 1.39-4.76) to be independently associated with more frequent antibiotic prescriptions for colds, upper respiratory tract infections, and bronchitis.Although antibiotics have little or no benefit for colds, upper respiratory tract infections, or bronchitis, these conditions account for a sizable proportion of total antibiotic prescriptions for adults by office-based physicians in the United States. Overuse of antibiotics is widespread across geographical areas, medical specialties, and payment sources. Therefore, effective strategies for changing prescribing behavior for these conditions will need to be broad based.

To assess whether outcomes and costs differ for elderly patients admitted to rehabilitation hospitals, subacute nursing homes, and traditional nursing homes.Inception cohort stratified by provider type and followed prospectively for 6 months.A total of 92 hospital-based units and freestanding facilities from 17 states.A total of 518 randomly selected patients with hip fracture and 485 stroke patients admitted from November 1991 to February 1994.At 6 months comparing community residence, recovery to premorbid levels in 5 activities of daily living (ADLs), Medicare costs, and the number of therapy and physician visits. Outcomes were adjusted for premorbid residence and function, caregiver availability, comorbid illness, admission function, cognition, depression, sensory deficits, and mobility impairments.On admission, rehabilitation hospital patients were more likely (P.001) to have caregivers and better cognitive and physical function. Hip fracture patients admitted to rehabilitation hospitals did not differ from patients admitted to nursing homes in returning to the community (adjusted odds ratio [OR], 1.3; 95% confidence interval [CI], 0.6-2.6) or in the number of ADLs recovered to premorbid level (difference, 0.09 ADL; 95% CI, -0.27-0.44), but stroke patients admitted to rehabilitation hospitals were more likely to return to the community (adjusted OR, 3.3; 95% CI, 1.5-7.2) and recover ADLs (difference, 0.63 ADL; 95% CI, 0.20-1.07). Subacute nursing home patients with stroke were more likely than traditional nursing home patients to return to the community (adjusted OR, 6.8; 95% CI, 2.2-21.4), there was no difference in return to the community for patients with hip fracture (adjusted OR, 1.6; 95% CI, 0.7-3.6), and there were no differences in recovery of ADLs for either condition. Medicare costs were greater (P.001) for rehabilitation hospital patients than for subacute nursing home patients, and the costs for subacute nursing home patients were greater (P=.03 for stroke and .009 for hip fracture) than for traditional nursing home patients.Study findings are consistent with enhanced outcomes for elderly patients with stroke treated in rehabilitation hospitals but not for patients with hip fracture. Subacute nursing homes were more effective than traditional nursing homes in returning patients with stroke to the community, despite comparable functional outcomes.

The incidence of digoxin toxicity among patients in hospitals has declined in recent years. To evaluate whether a similar decline has occurred in ambulatory care, we reviewed randomly selected medical records for 183 outpatients receiving ongoing treatment with digoxin at 10 urban and rural Department of Veterans Affairs Medical Centers in the Rocky Mountain region. The prevalence of traditional risk factors for digoxin toxicity--elevated serum digoxin and serum creatinine levels, hypokalemia, and a new prescription of an interacting drug-was established from computerized laboratory and pharmacy records. Of the 183 patients, 50 (27.3%) had one or more risk factors for digoxin toxicity: serum digoxin levels were elevated in 13.6% of patients in whom a level was obtained, with hypokalemia in 14.3%, elevated creatinine levels in 17.9%, and possible drug interactions in 5.5% of patients over a 1-year period. Nevertheless, digoxin toxicity occurred in only 2 persons (1.1% or 1.4 per 100 patient-years of treatment). We conclude that digoxin toxicity was rare in this group of outpatients, even in persons presumed to be at high risk because of metabolic abnormalities, increased digoxin concentrations, or the use of interacting drugs. The low rate of digoxin toxicity in outpatients parallels the decline in the incidence of toxicity observed in hospital-based studies.

The pharmacology and pharmacokinetics of finasteride are reviewed, and finasteride's clinical efficacy, adverse effects, and dosage in patients with benign prostatic hyperplasia (BPH) are described. Finasteride is a member of a new class of medications, the azasteroids, that have antiandrogenic activity limited to certain tissues, including the prostate gland. Finasteride inhibits the activity of 5 alpha-reductase, the enzyme necessary for converting testosterone to dihydrotestosterone in the prostate and other tissues. BPH is androgen dependent, and dihydrotestosterone is necessary for the hyperplasia to occur. Finasteride is well absorbed after oral administration; peak plasma concentration is reached in as little as one hour. Finasteride is approximately 90% bound to plasma proteins, is widely distributed, and is extensively metabolized by the liver. In clinical studies, finasteride has been effective in decreasing prostatic volume, increasing urinary flow rate, and decreasing the obstructive and irritative symptoms of BPH. Because of the heterogeneity of BPH, however, treatment is successful in only one third to one half of patients. Finasteride's adverse effects include decreased libido, ejaculatory disorders, and effects on prostate-specific antigen. The recommended dosage of finasteride is 5 mg/day orally. Therapy should be continued for at least six months before the clinical response is evaluated. Finasteride provides a pharmacologic alternative to surgery in patients with BPH.

The spectrin-based membrane skeleton of nonerythroid cells exhibits an unsuspected variety in protein interactions and regulatory mechanisms. Spectrin has at least two options in linkage to the membrane: ankyrin-mediated interaction with integral membrane proteins and direct linkages with ankyrin-independent sites. Ankyrin includes at least two families of functionally distinct isoforms, a general isoform expressed in many cells and a specialized isoform expressed in a limited number of cells and localized in a highly polarized distribution in these cells. Proteins likely to associate with the specialized isoforms of ankyrin based on association in vitro assays and co-localization in cells include the anion exchanger of erythrocytes and collecting ducts of kidney, the Na/K ATPase in distal tubule cells of kidney, and the voltage-dependent sodium channel in neuron. An additional mechanism for ankyrin diversity is processed variants of ankyrin with deleted regulatory domains that express binding sites unavailable to unprocessed ankyrinc Spectrin also can interact with high affinity with protein sites in synaptosomes and other membranes that are independent of ankyrin. Calmodulin in the presence of submicromolar concentrations of calcium is a competitive inhibitor of direct binding of spectrin to synaptosomal membranes but does not affect spectrin-ankyrin interactions. Thus the potential exists for differential regulation of spectrin-membrane interactions. The assembly state of the spectrin-actin lattice may also vary in certain cells. Adducin, a protein that promotes spectrin-actin interactions, is concentrated at sites of cell-cell contact in certain epithelial cells. These studies provide a low-resolution view of the spectrin skeleton and emphasize the possibilities for participation of this structure in a variety of functions including maintenance of specialized cell domains and participation in dynamic calcium-regulated processes.

Neonates are susceptible to infection since several elements of the immune system are deficient. At present, the most common pathogens are Group B streptococci and Escherichia coli. Prolonged rupture of membranes with amnionitis is a high-risk setting. Clinical signs suggesting neonatal sepsis include respiratory distress, poor feeding, hypothermia, seizures and hypotonia. After the sepsis work-up is completed, the initial choice of antibiotics is based on the prevailing organisms and antibiotic sensitivities within the community.

We report the results of a double-blind three-centre study, employing a cross-over design, set up to compare the efficacy of intra-articular injections of Myc 2095 (20 mg), triamcinolone hexacetonide (Lederspan) (20 mg) and placebo in 40 patients with synovitis of the knee joint. Each patient included in the study contributed data on 2 of the 3 treatment variables being compared. Seven clinical parameters were assessed every 6 weeks, while the doctor's and the patient's assessments were scored. Intra articular treatment both with Myc 2095 and triamcinolone hexacetonide proved to be effective. Placebo response was also very high. After the first Myc 2095 injection, improvement in "tenderness", "pain under load" and "swelling and hydrops" was significantly superior to that following placebo treatment. The evaluation of the second injections indicated a marked carry-over effect from the first course. This was also evident from the doctor's and patient's assessments. The importance of including a placebo in the evaluation of anti-phlogistic drugs in clinical trials, emerged from this study.