Erratum: Thermodynamics of memory erasure via a spin reservoir [Phys. Rev. E 103, 042140 (2021)].

This corrects the article DOI: 10.1103/PhysRevE.103.042140.

Thermodynamics of memory erasure via a spin reservoir.

Thermodynamics with multiple conserved quantities offers a promising direction for designing novel devices. For example, Vaccaro and Barnett's [J. A. Vaccaro and S. M. Barnett, Proc. R. Soc. A 467, 1770 (2011)1364-502110.1098/rspa.2010.0577; S. M. Barnett and J. A. Vaccaro, Entropy 15, 4956 (2013)ENTRFG1099-430010.3390/e15114956] proposed information erasure scheme, where the cost of erasure is solely in terms of a conserved quantity other than energy, allows for new kinds of heat engines. In recent work, we studied the discrete fluctuations and average bounds of the erasure cost in spin angular momentum. Here we clarify the costs in terms of the spin equivalent of work, called spinlabor, and the spin equivalent of heat, called spintherm. We show that the previously found bound on the erasure cost of γ^{-1}ln2 can be violated by the spinlabor cost, and only applies to the spintherm cost. We obtain three bounds for spinlabor for different erasure protocols and determine the one that provides the tightest bound. For completeness, we derive a generalized Jarzynski equality and probability of violation which shows that for particular protocols the probability of violation can be surprisingly large. We also derive an integral fluctuation theorem and use it to analyze the cost of information erasure using a spin reservoir.

Atteinte osseuse axiale de la sarcoïdose.

INTRODUCTION: Sarcoidosis is a multi-systemic disease characterized by non-caseating granulomas. Bone involvement initially considered as rare and described as a peripheral osteitis of the hands and feet, has recently been reported on the axial skeleton. CASE REPORTS: We report 4 clinical observations of sarcoidosis (3 women, 1 man) with axial bone involvement located to the spine (n = 4), pelvic bone (n = 2), scapular bone (n = 2), sternum (n = 1), mandible (n = 1). Sarcoidosis was already diagnosed in 3 cases. Bone pain was the main symptom, related in 3 cases. Magnetic resonance imaging appeared to be the best imaging test Histological bone analysis revealed typical granulomatous lesions (n = 2). Treatment included corticosteroids (n = 4), hydroxychloroquine (n = 2), and methotrexate (n = 2), with a good efficacy on bone pain in symptomatic patients. CONCLUSION: These 4 cases, as well as recent literature, illustrate bone involvement of sarcoidosis on the axial skeleton. It is symptomatic in around 50% of cases but may be a source of significant disability. Differential diagnosis with neoplasm may require bone histological analysis. This condition appears to be responsive to usual treatments for sarcoidosis.

Thermodynamics from first principles: Correlations and nonextensivity.

The standard formulation of thermostatistics, being based on the Boltzmann-Gibbs distribution and logarithmic Shannon entropy, describes idealized uncorrelated systems with extensive energies and short-range interactions. In this Rapid Communication, we use the fundamental principles of ergodicity (via Liouville's theorem), the self-similarity of correlations, and the existence of the thermodynamic limit to derive generalized forms of the equilibrium distribution for long-range-interacting systems. Significantly, our formalism provides a justification for the well-studied nonextensive thermostatistics characterized by the Tsallis distribution, which it includes as a special case. We also give the complementary maximum entropy derivation of the same distributions by constrained maximization of the Gibbs-Shannon entropy. The consistency between the ergodic and maximum entropy approaches clarifies the use of the latter in the study of correlations and nonextensive thermodynamics.

Motivational Strategies to Prevent Frailty in Older Adults with Diabetes: A Focused Review.

The prevalence of diabetes among Americans aged 65 years and older is greater than 25%. Medical expenditures for persons with diabetes are more than twice as high as those for patients without diabetes. Diabetes in older adults often times coexists with frailty, resulting in reduced quality of life and increased health-care use. Many older adults with type 2 diabetes have mobility impairments and experience falls, which contributes to increased frailty. Exercise has a protective effect for frailty and falls, yet less than half of persons with diabetes exercise and approximately one-quarter meet exercise recommendations. In addition to exercise, nutrition may help reduce the risk for falls; however, nutritional interventions have not been tested as a fall-prevention intervention. According to a review, there is insufficient evidence to create nutritional guidelines specific for frail older adults with type 2 diabetes. There is a need to motivate and empower older adults with type 2 diabetes to make lifestyle changes to prevent frailty. The purpose of this review was to identify and integrate what is known and what still needs to be done for this population to be successful in making health behavior changes to reduce frailty. There is some evidence that motivational approaches have worked for older adults with various chronic disease conditions. However, studies applying motivational strategies are lacking for frail older adults with type 2 diabetes. A novel motivational approach was described; it combines aspects of the Health Belief Model and Motivational Interviewing. Intervention studies incorporating this model are needed to determine whether this client-driven strategy can help various racial/ethnic populations make the sustainable health behavior changes of increasing exercise and healthy eating while taking into consideration physiological, psychological, and economic barriers.

Dietary Risk Factors by Race/Ethnicity, Age-Group, and Gender in a Representative Sample of US Older Adults.

OBJECTIVE: To explore the relationships among ethnicity/race, gender, demographics, age-group and dietary health in a nationally representative sample of older adults. DESIGN: Cross-sectional study. SETTING: Data for this study were collected by interview in the mobile examination centers from the National Health and Nutrition Examination Surveys, 2011 - 2012. PARTICIPANTS: U.S. representative sample of adults aged 55 years and older (N = 1860) from five ethnic/racial groups. All participants read, understood, and signed informed consent forms under data collection procedures by trained individuals. MEASUREMENTS: Sociodemographics were collected by trained interviewers using a general questionnaire. Food groups were determined by 24-hour recall using the validated USDA Automated Multiple-Pass Method. Data were presented by cross-tabulation and logistic regression to investigate relationships among race/ethnicity, gender, and age groups. RESULTS: Over 70% of older adults failed to consume 2.75 cups of combined fruits and vegetables. Other Hispanics (Hispanics excluding Mexican Americans) had higher Odds of sugar-containing food consumption compared to non-Hispanic Whites (adjusted model). Being older and female were protective factors for over-consumption of sugar. CONCLUSION: Older Americans are not meeting dietary guidelines and there are differences by gender and ethnicity. Since diet has been associated with quality of life and medical costs, public health interventions can benefit by knowing age-, gender- and racial/ethnic- specific dietary behaviors.

Inequivalence of pure state ensembles for open quantum systems: the preferred ensembles are those that are physically realizable.

An open quantum system in steady state rho(ss) can be represented by a weighted ensemble of pure states rho(ss) = [equation: see text] in infinitely many ways. A physically realizable (PR) ensemble is one for which some continuous measurement of the environment will collapse the system into a pure state /psi(t)>, stochastically evolving such that the proportion of time for which /psi(t)> = /psi(k)> equals Weierstrass p(k). Some, but not all, ensembles are PR. This constitutes the preferred ensemble fact. We present the necessary and sufficient conditions for a given ensemble to be PR, and illustrate the method by showing that the coherent state ensemble is not PR for an atom laser.

Pushing the quality envelope: a new outcomes management system.

This article is based on the authors' experience in designing and implementing outcomes management systems for large managed care organizations. Topics addressed include design of instruments, use of cost-effective technology, development of computerized decision-support tools, and methods for case-mix adjustment. The case-mix-adjustment models are based on a data repository of several thousand treatment cases with multiple measurement points across the course of treatment. Data from controlled and field studies are described. These data suggest that the outcomes management methods outlined in this article can result in significantly improved clinical outcomes and a more rational allocation of behavioral health care resources.

CT of blunt trauma bowel and mesenteric injury: typical findings and pitfalls in diagnosis.

Detection of bowel and mesenteric injury can be challenging in patients after blunt abdominal trauma. Early diagnosis and treatment are critical to decrease patient morbidity and mortality. Computed tomography (CT) has become the primary modality for the imaging of these patients. Signs of bowel perforation such as free air and contrast material are virtually pathognomonic. Bowel-wall thickening, free fluid, and mesenteric infiltration may be seen with this type of injury and partial thickness injuries. The authors present and discuss the range of CT findings seen with bowel and mesenteric injuries. Examples of observation and interpretation errors are also provided to highlight pitfalls encountered in the evaluation of abdominopelvic CT scans in patients after blunt trauma.

CT cystography in the evaluation of major bladder trauma.

Computed tomographic (CT) cystography has been advocated in lieu of conventional cystography in the initial work-up of patients with suspected urinary bladder trauma. CT cystography was applied to a classification scheme for bladder injury based on the degree of wall injury and anatomic location and demonstrated characteristic imaging features for each type of injury. In bladder contusion (type 1), findings are normal. In intraperitoneal rupture (type 2), CT cystography demonstrates intraperitoneal contrast material around bowel loops, between mesenteric folds, and in the paracolic gutters. Manifestations of interstitial injury (type 3) include intramural hemorrhage and submucosal extravasation of contrast material without transmural extension. In extraperitoneal rupture (type 4), the path of extravasated contrast material is variable: Extravasation is confined to the perivesical space in simple extraperitoneal ruptures, whereas in complex extraperitoneal ruptures, contrast material extends beyond the perivesical space and may dissect into a variety of fascial planes and spaces. Combined intra- and extraperitoneal rupture (type 5) usually demonstrates extravasation patterns that are typical for both types of injury. Familiarity with these CT cystographic features allows accurate classification of bladder injury and allows prompt, effective treatment with less radiation exposure than and without the added cost of conventional cystography.

Mechanism of inhibition of the human immunodeficiency virus type 1 reverse transcriptase by d4TTP: an equivalent incorporation efficiency relative to the natural substrate dTTP.

Among the clinically used nucleoside analogue inhibitors that target human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT), there is little detailed mechanistic information on the interactions of 2',3'-didehydro-2', 3'-dideoxythymidine-5'-triphosphate (d4TTP) with the enzyme. primer-template complex and how these interactions compare with those of the natural substrate, dTTP. Using a pre-steady-state kinetic analysis, we found that d4TTP was incorporated by HIV-1 RT just as efficiently as dTTP during both DNA- and RNA-dependent DNA synthesis. To our knowledge, these results represent the first observation of a 3'-modified nucleoside triphosphate analogue that has an incorporation efficiency comparable to that observed for the natural substrate during DNA synthesis by HIV-1 RT. This information provides a mechanistic basis for understanding the inhibition of HIV-1 RT by d4TTP as well as insight into the clinically observed lack of d4T resistance mutations in HIV-1 RT isolated from AIDS patients.

Involvement of phenylalanine 272 of DNA polymerase beta in discriminating between correct and incorrect deoxynucleoside triphosphates.

DNA polymerase beta is a small monomeric polymerase that participates in base excision repair and meiosis [Sobol, R., et al. (1996) Nature 379, 183-186; Plug, A., et al. (1997) Proc. Natl. Acad. Sci. U.S.A. 94, 1327-1331]. A DNA polymerase beta mutator mutant, F272L, was identified by an in vivo genetic screen [Washington, S., et al. (1997) Proc. Natl. Acad. Sci. U.S.A. 94, 1321-1326]. Residue 272 is located within the deoxynucleoside triphosphate (dNTP) binding pocket of DNA polymerase beta according to the known DNA polymerase beta crystal structures [Pelletier, H., et al. (1994) Science 264, 1891-1893; Sawaya, M., et al. (1997) Biochemistry 36, 11205-11215]. The F272L mutant produces errors at a frequency 10-fold higher than that of wild type in vivo and in the in vitro HSV-tk gap-filling assay. F272L shows an increase in the frequency of both base substitution mutations and frameshift mutations. Single-enzyme turnover studies of misincorporation by wild type and F272L DNA polymerase beta demonstrate that there is a 4-fold decrease in fidelity of the mutant as compared to that of the wild type enzyme for a G:A mismatch. The decreased fidelity is due primarily to decreased discrimination between the correct and incorrect dNTP during ground-state binding. These results suggest that the phenylalanine 272 residue is critical for maintaining fidelity during the binding of the dNTP.

Initiation of minus-strand DNA synthesis by human immunodeficiency virus type 1 reverse transcriptase.

The initiation of (-) strand DNA synthesis by HIV-1 reverse transcriptase was examined using a transient kinetic approach and a physiologically relevant RNA 18-mer/RNA 36-mer primer-template substrate. HIV-1 reverse transcriptase (RT) was found to bind with reasonably high affinity to the RNA/RNA substrate (K(d) = 90 nM), although the affinity for DNA/RNA and DNA/DNA substrates is higher (K(d) approximately 5 nM). A pre-steady-state burst of deoxynucleotide incorporation (k(obsd) = 1.0 s(-)(1)) into the RNA duplex was observed followed by a slower steady-state release of the elongated primer-template product (k(ss) = 0.58 s(-)(1)). The observation of a burst provides evidence that the release of the product is most likely the rate-limiting step in the overall kinetic pathway for the enzymatic reaction during a single deoxynucleotide incorporation event. Furthermore, the release of this product was 5-fold faster than that for elongated DNA/RNA and DNA/DNA products. Single-turnover experiments showed that there is a hyperbolic dependence of the rate of deoxynucleotide incorporation on the concentration of dCTP and demonstrated that the maximum rate of dCTP incorporation (k(pol) = 1.4 s(-)(1)) is 33- and 12-fold slower than the values for DNA/RNA and DNA/DNA primer-template substrates, respectively, while the affinity of dCTP (K(d) = 780 microM) for the HIV-1 RT.RNA/RNA complex is 56- and 71-fold weaker than the affinities for HIV-1 RT.DNA/RNA and HIV-1 RT.DNA/DNA complexes, respectively. Consequently, the overall efficiency of dCTP incorporation (k(pol)/K(d)) into the RNA/RNA substrate is approximately 1800- and 800-fold less than that for DNA/RNA and DNA/DNA substrates, respectively. These findings provide evidence which suggests that the HIV-1 RT.RNA/RNA.dCTP ternary complex exists in a significantly different conformation compared to ternary complexes involving DNA/RNA and DNA/DNA substrates. A model summarizing these results is presented, and implications for the molecular mechanism of initiation of (-) strand DNA synthesis by RT are discussed.

Implication of the tRNA initiation step for human immunodeficiency virus type 1 reverse transcriptase in the mechanism of 3'-azido-3'-deoxythymidine (AZT) resistance.

There is a lack of correlation between biochemical studies and the observed clinical resistance of AIDS patients on long-term AZT therapy. Mutant HIV-1 reverse transcriptase in the viral isolates from these patients shows a 100-fold decrease in sensitivity to AZT whereas little or no difference is observed in kinetic parameters in vitro using steady-state kinetic analysis. A pre-steady-state kinetic analysis was used to examine the binding and incorporation of 2'-deoxythymidine 5'-triphosphate (dTTP) and 3'-azido-3'-deoxythymidine 5'-triphosphate (AZTTP) by wild-type HIV-1 reverse transcriptase and a clinically important AZT-resistant mutant form of the enzyme (D67N, K70R, T215Y, K219Q) utilizing a physiologically relevant RNA 18-mer/RNA 36-mer primer-template substrate. It was determined that with this RNA/RNA substrate there is a 2.6-fold increase in the selection for incorporation of the natural nucleotide dTTP over the unnatural nucleoside analogue AZTTP by AZT-resistant reverse transcriptase as compared to its wild-type form. This observation indicates that the tRNALys initiation step plays an important role in the development of drug resistance. Furthermore, this result implies that the structural basis of AZT resistance in HIV-1 reverse transcriptase involves the conformation of the RNA-DNA junction (formed upon attachment of a deoxynucleotide to the RNA primer). Taken together, these observations suggest a new pharmacological basis for the development of more effective and novel AIDS drugs.

Skills training versus psychosocial occupational therapy for persons with persistent schizophrenia.

OBJECTIVE: The authors compared the community functioning of outpatients with persistent forms of schizophrenia after treatment with psychosocial occupational therapy or social skills training, with the latter conducted by paraprofessionals. METHOD: Eighty outpatients with persistent forms of schizophrenia were randomly assigned to receive either psychosocial occupational therapy or skills training for 12 hours weekly for 6 months, followed by 18 months of follow-up with case management in the community. Antipsychotic medication was prescribed through "doctor's choice" by psychiatrists who were blind to the psychosocial treatment assignments. RESULTS: Patients who received skills training showed significantly greater independent living skills during a 2-year follow-up of everyday community functioning. CONCLUSIONS: Skills training can be effectively conducted by paraprofessionals, with durability and generalization of the skills greater than that achieved by occupational therapists who provide their patients with psychosocial occupational therapy.