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Objective:Healthcare facilities are a well-known high-risk environment for transmission of M. tuberculosis, the etiologic agent of tuberculosis (TB) disease. However, the link between M. tuberculosis transmission in healthcare facilities and its role in the general TB epidemic is unknown. We estimated the proportion of overall TB transmission in the general population attributable to healthcare facilities.Methods:We combined data from a prospective, population-based molecular epidemiologic study with a universal electronic medical record (EMR) covering all healthcare facilities in Botswana to identify biologically plausible transmission events occurring at the healthcare facility. Patients with M. tuberculosis isolates of the same genotype visiting the same facility concurrently were considered an overlapping event. We then used TB diagnosis and treatment data to categorize overlapping events into biologically plausible definitions. We calculated the proportion of overall TB cases in the cohort that could be attributable to healthcare facilities.Results:In total, 1,881 participants had TB genotypic and EMR data suitable for analysis, resulting in 46,853 clinical encounters at 338 healthcare facilities. We identified 326 unique overlapping events involving 370 individual patients; 91 (5%) had biologic plausibility for transmission occurring at a healthcare facility. A sensitivity analysis estimated that 3%–8% of transmission may be attributable to healthcare facilities.Conclusions:Although effective interventions are critical in reducing individual risk for healthcare workers and patients at healthcare facilities, our findings suggest that development of targeted interventions aimed at community transmission may have a larger impact in reducing TB.

What is already known about this topic? A novel HIV infection surveillance initiative was implemented in Malawi to collect data on recent HIV infections among new diagnoses to characterize the epidemic and guide the public health response. What is added by this report? Higher proportions of recent infections were identified among females, persons aged

Supplementary Figure 1. Expression of GSC markers increases with therapy in vitro and in vivo; Supplementary Figure 2. In vitro evaluation of stemness and TMZ sensitivity in the TMZ rechallenged model; Supplementary Figure 3. In vitro Evaluation of GSC-specific reporter system; Supplementary Figure 4. Differentiation of PDX GBM line after culturing in the media with 10% FBS; Supplementary Figure 5. GSC-specific promoters functionally represent the GSC subpopulation; Supplementary Figure 6. Differentiation of PDX GBM line after culturing in the media Bone Morphogenic Protein 2 (BMP2); Supplementary Figure 7. HIFs can modulate the expression of GSC markers

Purpose: Glioblastoma multiforme (GBM) is an aggressive adult brain tumor with a poor prognosis. One hallmark of GBM is the accumulation of immunosuppressive and tumor-promoting CD4+FoxP3+GITR+ regulatory T cells (Tregs). Here, we investigated the role of indoleamine 2,3 dioxygenase (IDO) in brain tumors and the impact on Treg recruitment.Experimental Design: To determine the clinical relevance of IDO expression in brain tumors, we first correlated patient survival to the level of IDO expression from resected glioma specimens. We also used novel orthotopic and transgenic models of glioma to study how IDO affects Tregs. The impact of tumor-derived and peripheral IDO expression on Treg recruitment, GITR expression, and long-term survival was determined.Results: Downregulated IDO expression in glioma predicted a significantly better prognosis in patients. Coincidently, both IDO-competent and deficient mice showed a survival advantage bearing IDO-deficient brain tumors, when compared with IDO-competent brain tumors. Moreover, IDO deficiency was associated with a significant decrease in brain-resident Tregs, both in orthotopic and transgenic mouse glioma models. IDO deficiency was also associated with lower GITR expression levels on Tregs. Interestingly, the long-term survival advantage conferred by IDO deficiency was lost in T-cell–deficient mice.Conclusions: These clinical and preclinical data confirm that IDO expression increases the recruitment of immunosuppressive Tregs that lead to tumor outgrowth. In contrast, IDO deficiency decreases Treg recruitment and enhances T-cell–mediated tumor rejection. Thus, the data suggest a critical role for IDO-mediated immunosuppression in glioma and support the continued investigation of IDO–Treg interactions in the context of brain tumors. Clin Cancer Res; 18(22); 6110–21. ©2012 AACR.

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CCR Translation for This Article from IDO Expression in Brain Tumors Increases the Recruitment of Regulatory T Cells and Negatively Impacts Survival

PDF file, 477K, mRNA and protein expression of IDO.

PDF file, 370K, Brain tumor derived IDO and peripheral Tregs.

PDF file, 84K, Correlation of patient characteristics with IDO expression.

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Tuberculosis (TB) elimination requires interrupting transmission of Mycobacterium tuberculosis. We used a multidisciplinary approach to describe TB transmission in 2 sociodemographically distinct districts in Botswana (Kopanyo Study). During August 2012–March 2016, all patients who had TB were enrolled, their sputum samples were cultured, and M. tuberculosis isolates were genotyped by using 24-locus mycobacterial interspersed repetitive units–variable number of tandem repeats. Of 5,515 TB patients, 4,331 (79%) were enrolled. Annualized TB incidence varied by geography (range 66–1,140 TB patients/100,000 persons). A total of 1,796 patient isolates had valid genotyping results and residential geocoordinates; 780 (41%) patients were involved in a localized TB transmission event. Residence in areas with a high burden of TB, age

Statement of problem Although in vitro studies have investigated the accuracy of virtual interocclusal records, clinical research on their ability to register virtual dental casts accurately is lacking. Purpose The purpose of this clinical study was to evaluate the accuracy and reproducibility of the virtual interocclusal records of an intraoral scanning system compared with conventional polyvinyl siloxane (PVS) interocclusal records. Material and methods Three conventional interocclusal records followed by 3 virtual interocclusal records per side per participant were made in 10 participants. Three sites of close proximity (SCP) and 3 sites of clearance (SC) per side per participant were identified on the transilluminated conventional interocclusal PVS records for a total of 60 SCP and SC. The presence or absence of these sites on the virtual interocclusal records was analyzed by using an independent software program. Results The sensitivity for correct identification in the virtual interocclusal record was 87%, and its specificity was 95%. The positive predictive value was 95%, and the negative predictive value was 88%. For reproducibility, 74% of the SCP were detected consistently for all 3 repeated scans, and 92% of the SCs were identified accurately. Conclusions The accuracy of virtual interocclusal records in identifying interocclusal contacts is clinically acceptable. However, the method tends to miss interocclusal contacts rather than introducing false ones and can result in perforations between the opposing virtual casts. Repeated buccal occlusal scans made of the same side showed fair reproducibility, and this aspect would benefit from further investigation.

Contact investigation is one public health measure used to prevent tuberculosis by identifying and treating persons exposed to Mycobacterium tuberculosis. Contact investigations are a major tenet of global tuberculosis elimination efforts, but for many reasons remain ineffective. We describe a novel neighbor-based approach to reframe contact investigations.

Mycobacterium tuberculosis transmission dynamics in high-burden settings are poorly understood. Growing evidence suggests transmission may be characterized by extensive individual heterogeneity in secondary cases (i.e., superspreading), yet the degree and influence of such heterogeneity is largely unknown and unmeasured in high burden-settings. We conducted a prospective, population-based molecular epidemiology study of TB transmission in both an urban and rural setting of Botswana, one of the highest TB burden countries in the world. We used these empirical data to fit two mathematical models (urban and rural) that jointly quantified both the effective reproductive number, $$R$$ R , and the propensity for superspreading in each population. We found both urban and rural populations were characterized by a high degree of individual heterogeneity, however such heterogeneity disproportionately impacted the rural population: 99% of secondary transmission was attributed to only 19% of infectious cases in the rural population compared to 60% in the urban population and the median number of incident cases until the first outbreak of 30 cases was only 32 for the rural model compared to 791 in the urban model. These findings suggest individual heterogeneity plays a critical role shaping local TB epidemiology within subpopulations.

IntroductionCombining genomic and geospatial data can be useful for understanding Mycobacterium tuberculosis (Mtb) transmission in high tuberculosis burden settings.MethodsWe performed whole genome sequencing (WGS) on Mtb DNA extracted from sputum cultures from a population-based tuberculosis study conducted in 2012–2016 in Gaborone, Botswana. We used kernel density estimation, spatial K-functions, and created spatial distributions of phylogenetic trees. WGS-based clusters of isolates ≤5 single nucleotide polymorphisms were considered recent transmission, and large WGS-based clusters (≥10 members) were considered outbreaks.ResultsWe analyzed data from 1449 participants with culture-confirmed TB. Among these, 946 (65%) participants had both molecular and geospatial data. A total of 62 belonged to five large outbreaks (10–19 participants each). Geospatial clustering was detected in two of the five large outbreaks, suggesting heterogeneous spatial patterns within the community.ConclusionsIntegration of genomic and geospatial data identified distinct patterns of tuberculosis transmission in a high-tuberculosis burden setting. Targeted interventions in these smaller geographies may interrupt on-going transmission.

With a gradually increasing elderly population, the treatment of geriatric patients represents a major challenge for trauma and reconstructive surgery. Although, it is well established that aging affects bone metabolism, it is still controversial if aging impairs bone healing. Accordingly, we investigated fracture healing in young adult (3–4 months) and aged (16–18 months) CD-1 mice using a stable closed femoral fracture model. Bone healing was analyzed by radiographic, biomechanical and histological analysis at 1, 2, 3, 4 and 5 weeks after fracture. Our results demonstrated an increased callus diameter to femoral diameter ratio in aged animals at later time points of fracture healing when compared to young adult mice. Moreover, our biomechanical analysis revealed a significantly decreased bending stiffness at 3 and 4 weeks after fracture in aged animals. In contrast, at 5 weeks after fracture, the analysis showed no significant difference in bending stiffness between the two study groups. Additional histological analysis showed a delayed endochondral ossification in aged animals as well as a higher amounts of fibrous tissue at early healing time points. These findings indicate a delayed process of callus remodeling in aged CD-1 mice, resulting in a delayed fracture healing when compared to young adult animals. However, the overall healing capacity of the fractured femora was not affected by aging.

Non-union formation represents a major complication in trauma surgery. Adequate vascularization has been recognized as vital for bone healing. However, the role of vascularization in the pathophysiology of non-union formation remains elusive. This is due to difficulties in studying bone microcirculation in vivo. Therefore, we herein studied in a murine osteotomy model whether photoacoustic imaging may be used to analyze vascularization in bone healing and non-union formation. We found that oxygen saturation within the callus tissue is significantly lower in non-unions compared to unions and further declines over time. Moreover, the amount of total hemoglobin (HbT) within the callus tissue was markedly reduced in non-unions. Correlation analyses showed a strong positive correlation between microvessel density and HbT, indicating that photoacoustically determined HbT is a valid parameter to assess vascularization during bone healing. In summary, photoacoustic imaging is a promising approach to study vascular function and tissue oxygenation in bone regeneration.

Mycobacterium tuberculosis transmission dynamics in high-burden settings are poorly understood. Growing evidence suggests transmission may be characterized by extensive individual heterogeneity in secondary cases (i.e., superspreading), yet the degree and influence of such heterogeneity is largely unknown and unmeasured in high burden-settings. We conducted a prospective, population-based molecular epidemiology study of TB transmission in both an urban and rural setting of Botswana, one of the highest TB burden countries in the world. We used these empirical data to fit two mathematical models (urban and rural) that jointly quantified both the effective reproductive number, [Formula: see text], and the propensity for superspreading in each population. We found both urban and rural populations were characterized by a high degree of individual heterogeneity, however such heterogeneity disproportionately impacted the rural population: 99% of secondary transmission was attributed to only 19% of infectious cases in the rural population compared to 60% in the urban population and the median number of incident cases until the first outbreak of 30 cases was only 32 for the rural model compared to 791 in the urban model. These findings suggest individual heterogeneity plays a critical role shaping local TB epidemiology within subpopulations.

Background Mineworkers in Southern Africa have the highest rates of tuberculosis (TB) among working populations in the world (The World Bank, Benefits and costs associated with reducing tuberculosis among Southern Africa’s mineworkers, 2014), making mineworkers a key population for TB program efforts. The current evaluation aimed to characterize mineworkers and former (ex-) mineworkers, and assess knowledge, attitudes and practices related to TB and HIV care among mineworkers and healthcare workers (HCWs) in Zambia. Methods A mixed-methods evaluation of current and former (ex-) mineworkers and HCWs was conducted in the Copperbelt and North-Western provinces, Zambia. Knowledge, attitudes and practices (KAPs) related to TB care and policies were assessed using a structured survey. Focus Group Discussions (FGDs) were conducted with current and ex-mineworkers to understand perceptions, practices, and barriers related to accessing healthcare for TB. Results Overall, 2,792 mineworkers and 94 HCWs completed the KAP survey, and 206 (171 current, 71 ex-) mineworkers participated in FGDs. Mineworkers and ex-mineworkers were knowledgeable about TB symptoms (cough; 94%), transmission (81.7%) and treatment (99.2%). Yet, barriers to seeking care were evident with 30% of mineworkers experiencing cough, and 19% reporting 2 or more TB symptoms at the time of the survey. The majority of mineworkers (70.9%) were aware of policies barring persons from working after a diagnosis of TB, and themes from FGDs and HCW comments (n = 32/62; 51.6%) recognized fear of job loss as a critical barrier to providing timely screening and appropriate care for TB among mineworkers. The majority (76.9%) of mineworkers indicated they would not disclose their TB status to their supervisor, but would be willing to share their diagnosis with their spouse (73.8%). Conclusion Fear of job loss, driven by governmental policy and mistrust in mining companies, is a major barrier to healthcare access for TB among mineworkers in Zambia. As a result of these findings, the government policy prohibiting persons from working in the mines following TB disease is being repealed. However, major reforms are urgently needed to mitigate TB among mineworkers, including ensuring the rights of mineworkers and their communities to healthy living and working environments, improved social responsibility of mining companies, and facilitating choice and access to affordable, timely, and high-quality healthcare services.

Background: The UNAIDS 90-90-90 Fast-Track targets provide a framework for assessing coverage of HIV testing services (HTS) and awareness of HIV status – the “first 90.” In Kenya, the bulk of HIV testing targets are aligned to the five highest HIV-burden counties. However, we do not know if most of the new HIV diagnoses are in these five highest-burden counties or elsewhere.Methods: We analyzed facility-level HTS data in Kenya from 1 October 2015 to 30 September 2016 to assess the spatial distribution of newly diagnosed HIV-positives. We used the Moran's Index (Moran's I) to assess global and local spatial auto-correlation of newly diagnosed HIV-positive tests and Kulldorff spatial scan statistics to detect hotspots of newly diagnosed HIV-positive tests. For aggregated data, we used Kruskal-Wallis equality-of-populations non-parametric rank test to compare absolute numbers across classes.Results: Out of 4,021 HTS sites, 3,969 (98.7%) had geocodes available. Most facilities (3,034, 76.4%), were not spatially autocorrelated for the number of newly diagnosed HIV-positives. For the rest, clustering occurred as follows; 438 (11.0%) were HH, 66 (1.7%) HL, 275 (6.9%) LH, and 156 (3.9%) LL. Of the HH sites, 301 (68.7%) were in high HIV-burden counties. Over half of 123 clusters with a significantly high number of newly diagnosed HIV-infected persons, 73(59.3%) were not in the five highest HIV-burden counties. Clusters with a high number of newly diagnosed persons had twice the number of positives per 1,000,000 tests than clusters with lower numbers (29,856 vs. 14,172).Conclusions: Although high HIV-burden counties contain clusters of sites with a high number of newly diagnosed HIV-infected persons, we detected many such clusters in low-burden counties as well. To expand HTS where most needed and reach the “first 90” targets, geospatial analyses and mapping make it easier to identify and describe localized epidemic patterns in a spatially dispersed epidemic like Kenya's, and consequently, reorient and prioritize HTS strategies.

Tuberculosis caused by concurrent infection with multiple Mycobacterium tuberculosis strains (i.e., mixed infection) challenges clinical and epidemiologic paradigms. We explored possible transmission mechanisms of mixed infection in a population-based, molecular epidemiology study in Botswana during 2012-2016. We defined mixed infection as multiple repeats of alleles at >2 loci within a discrete mycobacterial interspersed repetitive unit-variable-number tandem-repeat (MIRU-VNTR) result. We compared mixed infection MIRU-VNTR results with all study MIRU-VNTR results by considering all permutations at each multiple allele locus; matched MIRU-VNTR results were considered evidence of recently acquired strains and nonmatched to any other results were considered evidence of remotely acquired strains. Among 2,051 patients, 34 (1.7%) had mixed infection, of which 23 (68%) had recently and remotely acquired strains. This finding might support the mixed infection mechanism of recent transmission and simultaneous remote reactivation. Further exploration is needed to determine proportions of transmission mechanisms in settings where mixed infections are prevalent.

Background: In a spatially well known and dispersed HIV epidemic, identifying geographic clusters with significantly higher HIV prevalence is important for focusing interventions for people living with HIV (PLHIV). Methods: We used Kulldorff spatial-scan Poisson model to identify clusters with high numbers of HIV-infected persons 15–64 years old. We classified PLHIV as belonging to either higher prevalence or lower prevalence (HP/LP) clusters, then assessed distributions of sociodemographic and biobehavioral HIV risk factors and associations with clustering. Results: About half of survey locations, 112/238 (47%) had high rates of HIV (HP clusters), with 1.1–4.6 times greater PLHIV adults observed than expected. Richer persons compared with respondents in lowest wealth index had higher odds of belonging to a HP cluster, adjusted odds ratio (aOR) 1.61 [95% confidence interval (CI): 1.13 to 2.3], aOR 1.66 (95% CI: 1.09 to 2.53), aOR 3.2 (95% CI: 1.82 to 5.65), and aOR 2.28 (95% CI: 1.09 to 4.78) in second, middle, fourth, and highest quintiles, respectively. Respondents who perceived themselves to have greater HIV risk or were already HIV-infected had higher odds of belonging to a HP cluster, aOR 1.96 (95% CI: 1.13 to 3.4) and aOR 5.51 (95% CI: 2.42 to 12.55), respectively; compared with perceived low risk. Men who had ever been clients of female sex worker had higher odds of belonging to a HP cluster than those who had never been, aOR 1.47 (95% CI: 1.04 to 2.08); and uncircumcised men vs circumcised, aOR 3.2 (95% CI: 1.74 to 5.8). Conclusions: HIV infection in Kenya exhibits localized geographic clustering associated with sociodemographic and behavioral factors, suggesting disproportionate exposure to higher HIV risk. Identification of these clusters reveals the right places for targeting priority-tailored HIV interventions.

During 2012–2015, 10 of 24 patients infected with matching genotypes of Mycobacterium tuberculosis received care at the same hospital in Gaborone, Botswana. Nosocomial transmission was initially suspected, but we discovered plausible sites of community transmission for 20 (95%) of 21 interviewed patients. Active case-finding at these sites could halt ongoing transmission.

IntroductionHigh antiretroviral therapy (ART) coverage and high rates of viral load suppression (VLS) should reduce transmission of HIV, and ultimately, HIV incidence and the number of new HIV diagnoses out of the number tested (HIV positivity). We used 3 years of HIV program data in Kenya to assess whether trends in the number of new HIV diagnoses were associated with ART coverage and VLS rates and spatial-temporally auto-correlated at county level.MethodsWe analyzed routine program county-level aggregate data on ART coverage and VLS (proportion of persons on ART with VL

Porous polyethylene (pPE) is a commonly used biomaterial in craniofacial reconstructive surgery. However, implant failure due to insufficient vascularization represents a major issue. To overcome this problem, we herein introduce an effective strategy to improve the vascularization and incorporation of pPE. Adipose tissue-derived microvascular fragments (MVF) from transgenic green fluorescent protein (GFP)+ mice were suspended in platelet-rich plasma (PRP) for the coating of pPE. PRP/MVF-coated pPE as well as PRP-coated and uncoated controls were subsequently implanted into the dorsal skinfold chamber and the flanks of GFP- wild-type mice to analyze their in vivo performance throughout 2, 4 and 8 weeks by means of intravital fluorescence microscopy, histology and immunohistochemistry. The GFP+/GFP- cross-over design allowed the identification of GFP+ MVF within the implants. Shortly after implantation, they rapidly reassembled into new blood-perfused microvascular networks, resulting in a significantly accelerated vascularization of PRP/MVF-coated pPE when compared to both controls. The overall numbers of rolling and adherent leukocytes within the microcirculation as well as macrophages, multi-nucleated giant cells and mast cells around the implants did not differ between the three groups. However, in contrast to uncoated controls, PRP/MVF-coated and PRP-coated pPE promoted pro-angiogenic M2 macrophage polarization at the implantation site. These findings demonstrate that PRP/MVF-coating represents a highly effective strategy to enhance the vascularization, biocompatibility and tissue incorporation of pPE. STATEMENT OF SIGNIFICANCE: The clinical in vivo performance of implanted biomaterials is crucially dependent on their adequate incorporation into the body. To achieve this, we herein introduce an effective biological coating strategy. Our results demonstrate that coating with PRP and MVF accelerates and enhances the vascularization, biocompatibility and tissue incorporation of porous polyethylene. Because this type of biological coating is easily applicable on any type of biomaterial, our approach may rapidly be translated into clinical practice to improve the outcome of various regenerative approaches.

We present a new procedure for nonparametric Bayesian estimation of regression functions. Specifically, our method makes use of an idea described in Fruhwirth-Schnatter and Wagner (2010) to impose linearity exactly (conditional upon an unobserved binary indicator), yet also permits departures from linearity while imposing smoothness of the regression curves. An advantage of this approach is that the posterior probability of linearity is essentially produced as a by-product of the procedure. We apply our methods in both generated data experiments as well as in an illustrative application involving the impact of body mass index (BMI) on labor market earnings.

Bayesian Econometric Methods examines principles of Bayesian inference by posing a series of theoretical and applied questions and providing detailed solutions to those questions. This second edition adds extensive coverage of models popular in finance and macroeconomics, including state space and unobserved components models, stochastic volatility models, ARCH, GARCH, and vector autoregressive models. The authors have also added many new exercises related to Gibbs sampling and Markov Chain Monte Carlo (MCMC) methods. The text includes regression-based and hierarchical specifications, models based upon latent variable representations, and mixture and time series specifications. MCMC methods are discussed and illustrated in detail - from introductory applications to those at the current research frontier - and MATLAB® computer programs are provided on the website accompanying the text. Suitable for graduate study in economics, the text should also be of interest to students studying statistics, finance, marketing, and agricultural economics.

The addition of flaxseed and amaranth on the physicochemical, functional and microstructural changes of instant-extruded cereals was evaluated. Six different mixtures were made with additions of amaranth (30%–50%) and flaxseed (10% and 15%) using maize grits and minor additives as supplementary ingredients and then extruded in a twin-screw extruder. The extrudates evaluated, had insoluble and soluble fiber contents increased with the proportion of amaranth and flaxseed. The mixture 4 (higher flaxseed content) presented highest soluble fiber percentage (1.9%). Extruded cereals had the lowest viscosity (

The addition of flaxseed and amaranth on the physicochemical, functional, and microstructural changes of instant-extruded products was evaluated. Six mixtures with different proportions of amaranth (18.7&ndash, 33.1%), flaxseed (6.6&ndash, 9.3%), maize grits (55.6&ndash, 67.3%) and minor ingredients (4.7%) were extruded in a twin-screw extruder. Insoluble and soluble fiber contents in extrudates increased as the proportions of amaranth and flaxseed increased. However, the highest flaxseed proportion had the highest soluble fiber content (1.9%). Extruded products with the highest proportion of flaxseed and amaranth resulted in the highest dietary fiber content and hardness values (5.2 N), which was correlated with the microstructural analysis where the crystallinity increased, resulting in larger, and more compact laminar structure. The extruded products with the highest maize grits proportion had the highest viscosity, expansion, and water absorption indexes, and the lowest water solubility index values. The mixtures with amaranth (18.7&ndash, 22.9%), flaxseed (8.6&ndash, 9.3%), and maize grits (63.8&ndash, 67.3%) resulted in extruded products with acceptable physicochemical and functional properties.

Listeners locate potential mates using species-specific vocal signals. As tetrapods transitioned from water to land, lungs replaced gills, allowing expiration to drive sound production. Some frogs then returned to water. Here we explore how air-driven sound production changed upon re-entry to preserve essential acoustic information on species identity in the secondarily aquatic frog genus Xenopus. We filmed movements of cartilage and muscles during evoked sound production in isolated larynges. Results refute the current theory for Xenopus vocalization, cavitation, and favor instead sound production by mechanical excitation of laryngeal resonance modes following rapid separation of laryngeal arytenoid discs. Resulting frequency resonance modes (dyads) are intrinsic to the larynx rather than due to neuromuscular control. Dyads are a distinctive acoustic signature. While their component frequencies overlap across species, their ratio is shared within each Xenopus clade providing information on species identity that could facilitate both conspecific localization and ancient species divergence. Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter)., eLife digest The voice is a unique characteristic that we use to identify one another – including someone's sex, age and mood. We speak by using air flow to vibrate our vocal folds, commonly known as vocal cords. The land-living ancestors of the African clawed frog Xenopus also used breath and vocal cords to communicate, but they returned to aquatic life 180 million years ago and had to evolve a different way to create sounds. Today’s Xenopus live in water and use a new mechanism that lets them sing for hours underwater without coming up to breathe. Males from each major group of Xenopus species produce courtship songs with harmonic intervals corresponding to an octave, a perfect fourth, or a major or minor third. Today's Xenopus species do not have any vocal cords. Instead, they have an elaborate set of vocal components: the muscles of the larynx contract paired, movable rods that end in discs. For the past 40 years, it was thought that these frogs create sounds by collapsing small air bubbles between the discs, similar to snapping shrimp. But such bubbles have never been observed, and exactly how these frogs manage to create sounds underwater has been a mystery. Here, Kwong-Brown et al. filmed the larynx as it was stimulated to produce sounds and discovered that the rapid separation of the discs excites the larynx and the surrounding tissues to create the harmonic frequencies. Then, to determine how the frog creates its harmonic intervals, Kwong-Brown et al. tried to ‘detune’ the larynx. In a series of experiments, they placed weights on the surface of the larynx, drilled a hole in the cartilage and filled it with helium, or introduced small glass beads. None of these attempts had any effect. However, rupturing the elastic cartilages within the larynx – which separate its internal cavity into three chambers – disrupted the harmonic intervals. This new way of creating underwater sounds helped to maintain the quality of the frog’s voice and may explain how Xenopus can shape its songs to convey crucial information to others, such as identifying species, sex and social intent.

The voice is a unique characteristic that we use to identify one another – including someone's sex, age and mood. We speak by using air flow to vibrate our vocal folds, commonly known as vocal cords. The land-living ancestors of the African clawed frog Xenopus also used breath and vocal cords to communicate, but they returned to aquatic life 180 million years ago and had to evolve a different way to create sounds. Today’s Xenopus live in water and use a new mechanism that lets them sing for hours underwater without coming up to breathe. Males from each major group of Xenopus species produce courtship songs with harmonic intervals corresponding to an octave, a perfect fourth, or a major or minor third. Today's Xenopus species do not have any vocal cords. Instead, they have an elaborate set of vocal components: the muscles of the larynx contract paired, movable rods that end in discs. For the past 40 years, it was thought that these frogs create sounds by collapsing small air bubbles between the discs, similar to snapping shrimp. But such bubbles have never been observed, and exactly how these frogs manage to create sounds underwater has been a mystery. Here, Kwong-Brown et al. filmed the larynx as it was stimulated to produce sounds and discovered that the rapid separation of the discs excites the larynx and the surrounding tissues to create the harmonic frequencies. Then, to determine how the frog creates its harmonic intervals, Kwong-Brown et al. tried to ‘detune’ the larynx. In a series of experiments, they placed weights on the surface of the larynx, drilled a hole in the cartilage and filled it with helium, or introduced small glass beads. None of these attempts had any effect. However, rupturing the elastic cartilages within the larynx – which separate its internal cavity into three chambers – disrupted the harmonic intervals. This new way of creating underwater sounds helped to maintain the quality of the frog’s voice and may explain how Xenopus can shape its songs to convey crucial information to others, such as identifying species, sex and social intent.

Statement of problem Evidence on the accuracy and reproducibility of the virtual interocclusal registration procedure and recommendations as to how to make a virtual interocclusal record are lacking. Purpose The purpose of this in vitro study was to assess whether virtual interocclusal registration records made at different locations around the arch affect the alignment of virtual casts, and to assess whether quadrant and complete arch scans have different effects on cast alignment when they are articulated with virtual interocclusal records. Material and methods Three sites of close proximity (SCPs) and 3 sites of clearance (SCs) were identified in each sextant of mounted zirconia master models. The SCPs and SCs were confirmed by using shimstock foil and the transillumination of an interocclusal impression. Complete-arch and quadrant scans of the master models were made with an intraoral scanner and registered with different virtual interocclusal registration records. The SCPs and SCs indicated by the scanner’s software and by independent software were compared according to the sensitivity, specificity, and predictive values of each method. Results Changed locations of SCPs were found depending on the location of the virtual interocclusal registration record. The intraoral scanner’s software contacts had a higher sensitivity of 92.86% and a negative predictive value of 84.21% than the contacts revealed by the independent software that exhibited a sensitivity of 69.05% and a negative predictive value of 70.45%. However, the intraoral scanner software had a lower specificity of 41.03% and a positive predictive value of 62.90% compared with the independent software, which exhibited a specificity of 79.49% and a positive predictive value of 78.38%. The quadrant scans had a higher sensitivity than did the complete-arch scans. Conclusions Different occlusal contacts are obtained from interocclusal registration scans in different segments of the dental arch. The difference is more obvious in complete-arch scans, where a tilting effect toward the site of the interocclusal registration scan was observed. Occlusal contacts obtained from interocclusal registration scans for quadrant scans had a higher sensitivity than did those for complete-arch scans.

Time-constant assumptions in discrete-response heterogeneity models can often be violated. To address this, a time-varying heterogeneity approach to model unobserved heterogeneity in ordered response data is considered. A Markov switching random parameters structure (which accounts for heterogeneity across observations) is proposed to accommodate both time-varying and time-constant (cross-sectional) unobserved heterogeneity in an ordered discrete-response probability model. A data augmented Markov Chain Monte Carlo algorithm for non-linear model estimation is developed to facilitate model estimation. The performance of the cross-sectional heterogeneity model and time-varying heterogeneity model are examined with vehicle crash-injury severity data. The time-varying heterogeneity model (Markov switching random parameters ordered probit) is found to provide the best overall model fit. Two roadway safety states are shown to exist and roadway segments transition between these two states according to Markov transition probabilities. The results demonstrate considerable promise for Markov switching models in a wide variety of applications.

Background: Since 2004, several African countries, including Namibia, have received assistance from the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). Aims: Gains have been documented in the safety and number of collected units in these countries, but the distribution of blood has not been described. Methods: Nine years of data on blood requests and issues from Namibia were stratified by region to describe temporal and spatial changes in the number and type of blood components issued to Namibian healthcare facilities nationally. Results: Between 2004-2007 (early years of PEPFAR support) and 2008-2011 (peak years of PEPFAR support), the average number of red cell units issued annually increased by 23.5% in seven densely populated but less developed regions in northern Namibia; by 30% in two regions with urban centers; and by 35.1% in four sparsely-populated rural regions. Summary/Conclusions: Investments in blood safety and a policy decision to emphasize distribution of blood to underserved regions improved blood availability in remote rural areas and increased the proportion of units distributed as components. However, disparities persist in the distribution of blood between Namibia's urban and rural regions.

Summary In this paper we, like several studies in the recent literature, employ a Bayesian approach to estimation and inference in models with endogeneity concerns by imposing weaker prior assumptions than complete excludability. When allowing for instrument imperfection of this type, the model is only partially identified, and as a consequence standard estimates obtained from the Gibbs simulations can be unacceptably imprecise. We thus describe a substantially improved ‘semi-analytic’ method for calculating parameter marginal posteriors of interest that only require use of the well-mixing simulations associated with the identifiable model parameters and the form of the conditional prior. Our methods are also applied in an illustrative application involving the impact of body mass index on earnings. Copyright © 2014 John Wiley & Sons, Ltd.

In anurans, male clasps can elicit release calls from either sex. Male release calls have been observed in many anuran genera and this vocal response is thus highly conserved. Female release calls, however, are not as prevalent, suggesting that evolutionary trajectories for anuran release calls differ by sex. We analyzed male and female release calls in all available species of Xenopus, a fully aquatic African genus. Phylogenetic relationships in this genus include three species groups, two of which are clades and one of which is characterized by a reticulated phylogeny due in part to hybridizations between species with different ploidy levels (Evans et al., 2004; Evans, 2008). In all species, males produce release calls when clasped by another male. Females in the reticulated group do not produce release calls, but females in the rest of the genus do. Release calls consist of click trains of variable durations and inter-call intervals. In both sexes, inter-click interval divides the genus into groups with different click rates and these groups are phylogenetically related. In general, inter-click interval is shorter in male than in female release calls. Across species and sexes, release calls are characterized by a single, low (∼1000 Hz) dominant frequency. In X. laevis Congo and X. borealis, clasp duration is longer for male–female than for male–male pairs and clasp duration is correlated with the number, but not the duration, of release calls in male–male pairs. We discuss evolutionary scenarios for release call traits as well as the sex difference in occurrence.

The United States is experiencing a major public health problem relating to increasing levels of excess body fat. This paper is about the relationship in the United States between trends in the distribution of body mass index (BMI), including trends in overweight and obesity, and demographic change. We provide estimates of the counterfactual distribution of BMI that would have been observed in 2003–2008 had demographics remained fixed at 1980 values, roughly the beginning of the period of increasing overweight and obesity. We find that changes in demographics are partly responsible for the changes in the population distribution of BMI and are capable of explaining about 8.6% of the increase in the combined rate of overweight and obesity among women and about 7.2% of the increase among men. We also use demographic projections to predict a BMI distribution and corresponding rates of overweight and obesity for 2050.

A comprehensive model stitching simulation architecture has been developed, which allows continuous, full flight-envelope simulation based on a collection of discrete-point linear models and trim data. The model stitching simulation architecture is applicable to any aircraft configuration readily modeled by state equations and for which test data can be obtained. Individual linear models and trim data for specific flight conditions are incorporated with nonlinear elements to produce a continuous, quasi-nonlinear simulation model. Extrapolation methods within the model stitching architecture permit accurate simulation of off-nominal aircraft loading configurations, including variations in weight, inertia, and center of gravity, and variations in altitude, which together minimize the required number of point models for full-envelope simulation. The model stitching simulation architecture is applied herein to a model of a CJ1 business jet and to a model of a UH-60 utility helicopter. For both the fixed-wing and the rotorcraft application, configuring the stitched simulation models with 8 discrete-point linear models (4 point models each at two altitudes) plus additional trim data was found to allow accurate simulation over the full airspeed and altitude envelope. Flight-test implications for the development of stitched models from flight-identified point models are presented for fixed-wing and rotorcraft applications.

Payday loans are small short-term loans that a borrower must repay or renew on his/her next payday. In states where payday lending is legal, many terms of these loans are regulated, ostensibly to protect the consumer from excessively burdensome lending practices. The existing literature on payday loans has primarily focused on estimating causal effects of access to those loans, including work by Morse (2011) , Skiba and Tobacman (2009) and Melzer (2011) . Using individual-level administrative records on borrowers in 38 states from an online payday lender, this paper departs from past work by estimating how payday loan regulation affects borrower behavior, specifically how much they choose to borrow, how many times they choose to renew the loan, and whether or not they choose to default. State-level variation in maximum loan sizes and renewal caps are used as exclusion restrictions for identification purposes. We pay particular attention to the calculation of posterior predictive distributions that summarize the sensitivities of borrower behavior to various changes in state-level policies.

For most frogs, advertisement calls are essential for reproductive success, conveying information on species identity, male quality, sexual state and location. While the evolutionary divergence of call characters has been examined in a number of species, the relative impacts of genetic drift or natural and sexual selection remain unclear. Insights into the evolutionary trajectory of vocal signals can be gained by examining how advertisement calls vary in a phylogenetic context. Evolution by genetic drift would be supported if more closely related species express more similar songs. Conversely, a poor correlation between evolutionary history and song expression would suggest evolution shaped by natural or sexual selection. Here, we measure seven song characters in 20 described and two undescribed species of African clawed frogs (genera Xenopus and Silurana) and four populations of X. laevis. We identify three call types — click, burst and trill — that can be distinguished by click number, call rate and intensity modulation. A fourth type is biphasic, consisting of two of the above. Call types vary in complexity from the simplest, a click, to the most complex, a biphasic call. Maximum parsimony analysis of variation in call type suggests that the ancestral type was of intermediate complexity. Each call type evolved independently more than once and call type is typically not shared by closely related species. These results indicate that call type is homoplasious and has low phylogenetic signal. We conclude that the evolution of call type is not due to genetic drift, but is under selective pressure.

We describe a new octoploid species of African clawed frog (Xenopus) from the Lendu Plateau in the northern Albertine Rift of eastern Democratic Republic of the Congo. This species is the sister taxon of Xenopus vestitus (another octoploid), but is distinguished by a unique morphology, vocalization and molecular divergence in mitochondrial and autosomal DNA. Using a comprehensive genetic sample, we provide new information on the species ranges and intra-specific diversity of African clawed frogs from the Albertine Rift, including the details of a small range extension for the critically endangered Xenopus itombwensis and previously uncharacterized variation in Xenopus laevis. We also detail a new method for generating cytogenetic preparations in the field that can be stored at room temperature for up to 3 weeks. While extending our understanding of the extant diversity in the Albertine Rift, this new species highlights components of species diversity in ancestral African clawed frogs that are not represented by known extant descendants.

Introduction Using spatial–temporal analyses to understand coverage and trends in elimination of mother-to-child transmission of HIV (e-MTCT) efforts may be helpful in ensuring timely services are delivered to the right place. We present spatial–temporal analysis of seven years of HIV early infant diagnosis (EID) data collected from 12 districts in western Kenya from January 2007 to November 2013, during pre-Option B+ use. Methods We included in the analysis infants up to one year old. We performed trend analysis using extended Cochran–Mantel–Haenszel stratified test and logistic regression models to examine trends and associations of infant HIV status at first diagnosis with: early diagnosis ( Results Median age was two months, interquartile range 1.5–5.8 months. Unadjusted pooled positive rate was 11.8% in the seven-years period and declined from 19.7% in 2007 to 7.0% in 2013, p < 0.01. Uptake of testing ≤8 weeks after birth was under 50% in 2007 and increased to 64.1% by 2013, p < 0.01. By 2013, the overall standardized MTCT rate was 447 infections per 100,000 live births. Based on Bayesian deviance information criterion comparisons, the spatial–temporal model with maternal and infant covariates was best in explaining geographical variation in MTCT. Discussion Improved EID uptake and reduced MTCT rates are indicators of progress towards e-MTCT. Cojoined analysis of time and covariates in a spatial context provides a robust approach for explaining differences in programmatic impact over time. Conclusion During this pre-Option B+ period, the prevention of mother to child transmission program in this region has not achieved e-MTCT target of ≤50 infections per 100,000 live births. Geographical disparities in program achievements may signify gaps in spatial distribution of e-MTCT efforts and could indicate areas needing further resources and interventions.

We investigate the extent to which dichotomous choice referenda responses are shaped by whether the individual believes the survey itself will ultimately impact policy. Using survey data from the Iowa Lakes Project, we test this supposition. Specifically, we employ a Bayesian treatment effect model in which the degree of perceived consequentiality, measured as an ordinal response, is permitted to have a structural impact on willingness to pay (WTP) for a hypothetical environmental improvement. We test whether the estimated WTP distributions are the same for each value of the ordinal response. In our survey data, a subsample of individuals were randomly assigned supporting information suggesting that their responses to the questionnaires were important and will have an impact on policy decisions. In conjunction with a Bayesian posterior simulator, we use this source of exogenous variation to identify the structural impacts of consequentiality perceptions on willingness to pay, while controlling for the potential of confounding on unobservables. We find evidence consistent with a “knife-edge” result, namely that the willingness to pay distributions are equal among those believing the survey to be at least minimally consequential, and different for those believing that the survey is irrelevant for policy purposes.