Discrete Information from CHL Black Holes

AdS_2/CFT_1 correspondence predicts that the logarithm of a Z_N twisted index over states carrying a fixed set of charges grows as 1/N times the entropy of the black hole carrying the same set of charges. In this paper we verify this explicitly by calculating the microscopic Z_N twisted index for a class of states in the CHL models. This demonstrates that black holes carry more information about the microstates than just the total degeneracy.Comment: LaTeX file, 24 pages; v2: references adde

A Twist in the Dyon Partition Function

In four dimensional string theories with N=4 and N=8 supersymmetries one can often define twisted index in a subspace of the moduli space which captures additional information on the partition function than the ones contained in the usual helicity trace index. We compute several such indices in type IIB string theory on K3 x T^2 and T^6, and find that they share many properties with the usual helicity trace index that captures the spectrum of quarter BPS states in N=4 supersymmetric string theories. In particular the partition function is a modular form of a subgroup of Sp(2,Z) and the jumps across the walls of marginal stability are controlled by the residues at the poles of the partition function. However for large charges the logarithm of this index grows as 1/n times the entropy of a black hole carrying the same charges where n is the order of the symmetry generator that is used to define the twisted index. We provide a macroscopic explanation of this phenomenon using quantum entropy function formalism. The leading saddle point corresponding to the attractor geometry fails to contribute to the twisted index, but a Z_n orbifold of the attractor geometry produces the desired contribution.Comment: LaTeX file, 35 pages; v2: references adde

Internal medicine residency training for unhealthy alcohol and other drug use: recommendations for curriculum design

<p>Abstract</p> <p>Background</p> <p>Unhealthy substance use is the spectrum from use that risks harm, to use associated with problems, to the diagnosable conditions of substance abuse and dependence, often referred to as substance abuse disorders. Despite the prevalence and impact of unhealthy substance use, medical education in this area remains lacking, not providing physicians with the necessary expertise to effectively address one of the most common and costly health conditions. Medical educators have begun to address the need for physician training in unhealthy substance use, and formal curricula have been developed and evaluated, though broad integration into busy residency curricula remains a challenge.</p> <p>Discussion</p> <p>We review the development of unhealthy substance use related competencies, and describe a curriculum in unhealthy substance use that integrates these competencies into internal medicine resident physician training. We outline strategies to facilitate adoption of such curricula by the residency programs. This paper provides an outline for the actual implementation of the curriculum within the structure of a training program, with examples using common teaching venues. We describe and link the content to the core competencies mandated by the Accreditation Council for Graduate Medical Education, the formal accrediting body for residency training programs in the United States. Specific topics are recommended, with suggestions on how to integrate such teaching into existing internal medicine residency training program curricula.</p> <p>Summary</p> <p>Given the burden of disease and effective interventions available that can be delivered by internal medicine physicians, teaching about unhealthy substance use must be incorporated into internal medicine residency training, and can be done within existing teaching venues.</p

Chronic pain among homeless persons: characteristics, treatment, and barriers to management

<p>Abstract</p> <p>Background</p> <p>Little information is available on the problem of chronic pain among homeless individuals. This study aimed to describe the characteristics of and treatments for chronic pain, barriers to pain management, concurrent medical conditions, and substance use among a representative sample of homeless single adult shelter users who experience chronic pain in Toronto, Canada.</p> <p>Methods</p> <p>Participants were randomly selected at shelters for single homeless adults between September 2007 and February 2008 and screened for chronic pain, defined as having pain in the body for ≥ 3 months or receiving treatment for pain that started ≥ 3 months ago. Cross-sectional surveys obtained information on demographic characteristics, characteristics of and treatments for chronic pain, barriers to pain management, concurrent medical conditions, and substance use. Whenever possible, participants' physicians were also interviewed.</p> <p>Results</p> <p>Among 152 homeless participants who experienced chronic pain, 11 (8%) were classified as Chronic Pain Grade I (low disability-low intensity), 47 (32%) as Grade II (low disability-high intensity), 34 (23%) as Grade III (high disability-moderately limiting), and 54 (37%) as Grade IV (high disability-severely limiting). The most common self-reported barriers to pain management were stress of shelter life, inability to afford prescription medications, and poor sleeping conditions. Participants reported using over-the-counter medications (48%), street drugs (46%), prescribed medications (43%), and alcohol (29%) to treat their pain. Of the 61 interviewed physicians, only 51% reported treating the patient's pain. The most common physician-reported difficulties with pain management were reluctance to prescribe narcotics due to the patient's history of substance abuse, psychiatric comorbidities, frequently missed appointments, and difficulty getting the patient to take medications correctly.</p> <p>Conclusions</p> <p>Clinicians who provide healthcare for homeless people should screen for chronic pain and discuss barriers to effective pain management with their patients.</p

Addiction Treatment and Stable Housing among a Cohort of Injection Drug Users

Background: Unstable housing and homelessness is prevalent among injection drug users (IDU). We sought to examine whether accessing addiction treatment was associated with attaining stable housing in a prospective cohort of IDU in Vancouver, Canada. Methods: We used data collected via the Vancouver Injection Drug User Study (VIDUS) between December 2005 and April 2010. Attaining stable housing was defined as two consecutive ‘‘stable housing’ ’ designations (i.e., living in an apartment or house) during the follow-up period. We assessed exposure to addiction treatment in the interview prior to the attainment of stable housing among participants who were homeless or living in single room occupancy (SRO) hotels at baseline. Bivariate and multivariate associations between the baseline and time-updated characteristics and attaining stable housing were examined using Cox proportional hazard regression models. Principal Findings: Of the 992 IDU eligible for this analysis, 495 (49.9%) reported being homeless, 497 (50.1%) resided in SRO hotels, and 380 (38.3%) were enrolled in addiction treatment at the baseline interview. Only 211 (21.3%) attained stable housing during the follow-up period and of this group, 69 (32.7%) had addiction treatment exposure prior to achieving stable housing. Addiction treatment was inversely associated with attaining stable housing in a multivariate model (adjusted hazard ratio [AHR] = 0.71; 95 % CI: 0.52–0.96). Being in a partnered relationship was positively associated with the primary outcom

On the Strength of First Order Phase Transitions

Electroweak baryogenesis may solve one of the most fundamental questions we can ask about the universe, that of the origin of matter. It has become clear in the past few years that it also poses a multi-faceted challenge. In order to compute the tiny primordial baryonic excess, we probably must invoke physics beyond the standard model (an exciting prospect for most people), we must push perturbation theory to its ``limits'' (or beyond), and we must deal with nonequilibrium aspects of the phase transition. In this talk, I focus mainly on the latter issue, that of nonequilibrium aspects of first order transitions. In particular, I discuss the elusive question of ``weakness''. What does it mean to have a weak first order transition, and how can we distinguish between weak and strong? I argue that weak and strong transitions have very different dynamics; while strong transitions proceed by the usual bubble nucleation mechanism, weak transitions are characterized by a mixing of phases as the system reaches the critical temperature from above. I show that it is possible to clearly distinguish between the two, and discuss consequences for studies of first order transitions in general. (Invited talk given at the ``Electroweak Physics and the Early Universe'' workshop, Sintra, March 23-25, 1994.)Comment: 16 pages, 4 figures not included (can be obtained from hep-ph/9403310, or by request) RevTeX, DART-HEP-94/0

Lithocholic Acid Is an Eph-ephrin Ligand Interfering with Eph-kinase Activation

Eph-ephrin system plays a central role in a large variety of human cancers. In fact, alterated expression and/or de-regulated function of Eph-ephrin system promotes tumorigenesis and development of a more aggressive and metastatic tumour phenotype. In particular EphA2 upregulation is correlated with tumour stage and progression and the expression of EphA2 in non-trasformed cells induces malignant transformation and confers tumorigenic potential. Based on these evidences our aim was to identify small molecules able to modulate EphA2-ephrinA1 activity through an ELISA-based binding screening. We identified lithocholic acid (LCA) as a competitive and reversible ligand inhibiting EphA2-ephrinA1 interaction (Ki = 49 µM). Since each ephrin binds many Eph receptors, also LCA does not discriminate between different Eph-ephrin binding suggesting an interaction with a highly conserved region of Eph receptor family. Structurally related bile acids neither inhibited Eph-ephrin binding nor affected Eph phosphorylation. Conversely, LCA inhibited EphA2 phosphorylation induced by ephrinA1-Fc in PC3 and HT29 human prostate and colon adenocarcinoma cell lines (IC50 = 48 and 66 µM, respectively) without affecting cell viability or other receptor tyrosine-kinase (EGFR, VEGFR, IGFR1β, IRKβ) activity. LCA did not inhibit the enzymatic kinase activity of EphA2 at 100 µM (LANCE method) confirming to target the Eph-ephrin protein-protein interaction. Finally, LCA inhibited cell rounding and retraction induced by EphA2 activation in PC3 cells. In conclusion, our findings identified a hit compound useful for the development of molecules targeting ephrin system. Moreover, as ephrin signalling is a key player in the intestinal cell renewal, our work could provide an interesting starting point for further investigations about the role of LCA in the intestinal homeostasis

A web-based Alcohol Clinical Training (ACT) curriculum: Is in-person faculty development necessary to affect teaching?

<p>Abstract</p> <p>Background</p> <p>Physicians receive little education about unhealthy alcohol use and as a result patients often do not receive efficacious interventions. The objective of this study is to evaluate whether a free web-based alcohol curriculum would be used by physician educators and whether in-person faculty development would increase its use, confidence in teaching and teaching itself.</p> <p>Methods</p> <p>Subjects were physician educators who applied to attend a workshop on the use of a web-based curriculum about alcohol screening and brief intervention and cross-cultural efficacy. All physicians were provided the curriculum web address. Intervention subjects attended a 3-hour workshop including demonstration of the website, modeling of teaching, and development of a plan for using the curriculum. All subjects completed a survey prior to and 3 months after the workshop.</p> <p>Results</p> <p>Of 20 intervention and 13 control subjects, 19 (95%) and 10 (77%), respectively, completed follow-up. Compared to controls, intervention subjects had greater increases in confidence in teaching alcohol screening, and in the frequency of two teaching practices – teaching about screening and eliciting patient health beliefs. Teaching confidence and teaching practices improved significantly in 9 of 10 comparisons for intervention, and in 0 comparisons for control subjects. At follow-up 79% of intervention but only 50% of control subjects reported using any part of the curriculum (p = 0.20).</p> <p>Conclusion</p> <p>In-person training for physician educators on the use of a web-based alcohol curriculum can increase teaching confidence and practices. Although the web is frequently used for disemination, in-person training may be preferable to effect widespread teaching of clinical skills like alcohol screening and brief intervention.</p

Thrombospondin-2 and SPARC/osteonectin are critical regulators of bone remodeling

Thrombospondin-2 (TSP2) and osteonectin/BM-40/SPARC are matricellular proteins that are highly expressed by bone cells. Mice deficient in either of these proteins show phenotypic alterations in the skeleton, and these phenotypes are most pronounced under conditions of altered bone remodeling. For example, TSP2-null mice have higher cortical bone volume and are resistant to bone loss associated with ovariectomy, whereas SPARC-null mice have decreased trabecular bone volume and fail to demonstrate an increase in bone mineral density in response to a bone-anabolic parathyroid hormone treatment regimen. In vitro, marrow stromal cell (MSC) osteoprogenitors from TSP2-null mice have increased proliferation but delayed formation of mineralized matrix. Similarly, in cultures of SPARC-null MSCs, osteoblastic differentiation and mineralized matrix formation are decreased. Overall, both TSP2 and SPARC positively influence osteoblastic differentiation. Intriguingly, both of these matricellular proteins appear to impact MSC fate through mechanisms that could involve the Notch signaling system. This review provides an overview of the role of TSP2 and SPARC in regulating bone structure, function, and remodeling, as determined by both in vitro and in vivo studies

Clinical practice: Breastfeeding and the prevention of allergy

The increase in allergic disease prevalence has led to heightened interest in the factors determining allergy risk, fuelled by the hope that by influencing these factors one could reduce the prevalence of allergic conditions. The most important modifiable risk factors for allergy are maternal smoking behaviour and the type of feeding. A smoke-free environment for the child (to be), exclusive breastfeeding for 4–6 months and the postponement of supplementary feeding (solids) until 4 months of age are the main measures considered effective. There is no place for restricted diets during pregnancy or lactation. Although meta-analyses suggest that hypoallergenic formula after weaning from breastfeeding grants protection against the development of allergic disease, the evidence is limited and weak. Moreover, all current feeding measures aiming at allergy prevention fail to show effects on allergic manifestations later in life, such as asthma. In conclusion, the allergy preventive effect of dietary interventions in infancy is limited. Counselling of future parents on allergy prevention should pay attention to these limitations