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7T MRI offers significant benefits to spatial and contrast resolution compared to lower field strengths. This superior image quality can help better delineate targets in stereotactic neurosurgical procedures; however, the potential for increased geometric distortions at 7T has impaired its widespread use for these applications. Image geometric distortions can be due to distortions of BThe purpose of this study was to investigate the use of 7T MRI for neurosurgical frameless stereotactic navigation procedures. Image geometric distortions at the skin surface in 7T images were minimized and compared to results from clinical 3T frameless imaging protocols.A 3D-printed grid phantom filled with oil was designed to perform a fine calibration of the 7T imaging gradients, and an oil-filled head phantom with internal targets was used to determine ground truth (from computed tomography [CT]) positioning errors. Three volunteers and the head phantom were imaged consecutively at 3T and 7T. Ten skin-adhesive fiducial markers were placed on each subject's exposed skin surface at standard clinical placement locations for frameless procedures. Imaging sequences included MPRAGE (three bandwidths at 7T: 400, 690, and 1020 Hz/pixel, and one at 3T: 400 Hz/pixel), T2 SPACE, and T2 SPACE FLAIR acquisitions. An additional GRE field map was acquired on both scanners using a multi-echo GRE sequence. Custom Matlab code was used to perform additional distortion correction of the images using the unwrapped field maps. Fiducial localization was performed with 3D Slicer, with absolute fiducial positioning errors determined in phantom experiments following rigid registration to the CT images. For human experiments, 3T and 7T images were registered and relative differences in fiducial locations were compared using two-tailed paired t-tests.Phantom measurements at 7T yielded gradient distance scaling errors of 1.1%, 2.2%, and 1.0% along the x-, y-, and z-axes, respectively. These system miscalibrations were traced back to phantom manufacturing deviations in the sphericity of the vendor's gradient calibration phantom. Correction factors along each gradient axis were applied, and afterward, geometric distortions of less than 1 mm were obtained in the 7T MR head phantom images for the 1020 Hz/pixel bandwidth MPRAGE sequence. For the human subjects, four fiducial locations were excluded from the analysis due to patient positioning differences. Differences between 3T and 7T MPRAGE with low/medium/high bandwidth were 2.2 /2.6/2.3 mm, respectively, before the correction, reducing to 1.6/1.3/1.0 mm after the correction (p 0.001). T2 SPACE and T2 SPACE FLAIR yielded a similar pattern when the correction was applied, decreasing from 2.1 to 0.8 mm, and 2.6 to 1.0 mm, respectively.7T MRI can be used to perform frameless presurgical planning with skin-adhesive fiducials. Geometric distortions can be reduced to a clinically relevant level (errors ∼1 mm) with no significant susceptibility-related distortions, by using high receiver bandwidth, ensuring gradients are properly calibrated, and placing skin fiducials in areas where distortions from patient positioning are minimal.

Understanding the environmental mechanisms that govern population change is a fundamental objective in ecology. Although the determination of how top-down and bottom-up drivers affect demography is important, it is often equally critical to understand the extent to which, environmental conditions that underpin these drivers fluctuate across time. For example, associations between climate and both food availability and predation risk may suggest the presence of trophic interactions that may influence inferences made from patterns in ecological data. Analytical tools have been developed to account for these correlations, while providing opportunities to ask novel questions regarding how populations change across space and time. Here, we combine two modeling disciplines-path analysis and mark-recapture-recovery models-to explore whether shifts in sea-surface temperatures (SSTs) influenced top-down (entanglement in fishing equipment) or bottom-up (forage fish production) population constraints over 60 years, and the extent to which these covarying processes shaped the survival of a long-lived seabird, the Royal tern. We found that hemispheric trends in SST were associated with variation in the amount of fish harvested along the Atlantic coast of North America and in the Caribbean, whereas reductions in forage fish production were mostly driven by shifts in the amount of fish harvested by commercial fisheries throughout the North Atlantic the year prior. Although the indirect (i.e., stock depletion) and direct (i.e., entanglement) impacts of commercial fishing on Royal tern mortality has declined over the last 60 years, increased SSTs during this time period has resulted in a comparable increase in mortality risk, which disproportionately impacted the survival of the youngest age-classes of Royal terns. Given climate projections for the North Atlantic, our results indicate that threats to Royal tern population persistence in the Mid-Atlantic will most likely be driven by failures to recruit juveniles into the breeding population.

Background: Shock index (SI) equals the ratio of heart rate (HR) to systolic blood pressure (SBP) with clinical evidence that it is more sensitive for trauma patient status assessment and prediction of outcome compared to either HR or SBP alone. We used lower body negative pressure (LBNP) as a human model of central hypovolemia and compensatory reserve measurement (CRM) validated for accurate tracking of reduced central blood volume to test the hypotheses that SI: 1) presents a late signal of central blood volume status; 2) displays poor sensitivity and specificity for predicting the onset of hemodynamic decompensation; and 3) cannot identify individuals at greatest risk for the onset of circulatory shock. Methods: We measured HR, SBP and CRM in 172 human subjects (19 to 55 years) during progressive LBNP designed to determine tolerance to central hypovolemia as a model of hemorrhage. Subjects were subsequently divided into those with high (HT; n = 118) and low (LT; n = 54) tolerance based on completion of 60 mmHg LBNP. The time course relationship between SI and CRM was determined and Receiver Operating Characteristic (ROC) Area Under the Curve (AUC) was calculated for sensitivity and specificity of CRM and SI to predict hemodynamic decompensation using clinically defined thresholds of 40% for CRM and 0.9 for SI. Results: The time and level of LBNP required to reach a SI = 0.9 (~60 mmHg LBNP) was significantly greater (P < 0.001) compared to CRM that reached 40% at ~40 mmHg LBNP. SI did not differ between HT and LT subjects at 45 mmHg LBNP levels. ROCAUC for CRM was 0.95 (95%CI = 0.94-0.97) compared to 0.91 (0.89-0.94) for SI (P = 0.0002). Conclusions: Despite high sensitivity and specificity, SI delays time to detect reductions in central blood volume with failure to distinguish individuals with varying tolerances to central hypovolemia. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

An important feature enabled by Photon-Counting Detector (PCD) CT is the simultaneous acquisition of multi-energy data, which can produce virtual monoenergetic images (VMIs) at a high spatial resolution. However, noise levels observed in the high-resolution (HR) VMIs are markedly increased. Recent work involving deep learning methods has shown great potential in CT image denoising. Many CNN applications involve training using spatially co-registered low- and high-dose CT images featuring high and low image noise, respectively. However, this is implausible in routine clinical practice. Further, typical denoising methods treat each VMI energy level independently, without consideration of the valuable information in the spectral domain. To overcome these obstacles, we propose a prior knowledge-aware iterative denoising neural network (PKAID-Net). PKAID-Net offers two major benefits: first, it utilizes spectral information by including a lower-noise VMI as a prior input; and second, it iteratively constructs refined datasets for neural network training to improve the denoising performance. This study includes 10 patient coronary CT angiography (CTA) exams acquired on a clinical HR PCD-CT (NAEOTOM Alpha, Siemens Healthineers). The HR VMIs were reconstructed at 50 and 70 keV, using a sharp kernel (Bv68) and thin (0.6 mm, 0.3 mm increment) slice thickness. Results showed that the PKAID-Net provided a noise reduction of 96% and 70% relative to FBP and iterative reconstruction, respectively while maintaining spatial and spectral fidelity and a natural noise texture. These results demonstrate the noise reduction capacity of PKAID-Net as applied to cutting-edge PCD-CT data to enable HR, multi-energy cardiac CT imaging.

The mother-daughter dyad is a powerful relationship known to impact health and wellbeing of daughters throughout their life. This article examined studies focused on factors associated with daughter's positive body image through the mother-daughter relationship. In this systematic review searches were performed for English-language, peer-reviewed articles and dissertations published between 1955 to 2020 in the following databases: Family Studies Abstracts, ERIC, PsycINFO, PubMED, Scopus, and ProQuest Dissertations and Theses Global. Out of 444 potential records after removing duplicates, four were fully reviewed and synthesized. Study outcomes were analyzed through thematic analysis resulting in three major themes relating to the mother-daughter relationship as a facilitator for daughter's positive body image: (1) maternal role modeling of healthy behaviors; (2) positive body talk and communication; (3) relational connection.

Here I evaluate Andean concepts understood from the Quechua and Aymara languages to test their applicability to Moche archaeology—a region where the languages once spoken are now extinct. By focusing on geographical features common to the highlands and the coast (mountains and rivers) and archaeological evidence, I look at broad patterns of Moche material culture and consider how these relate to canal-fed irrigation systems, ceramic spatial patterning and fractaline socio-political organization documented in the colonial-era Chicama Valley. I then present a case study from Licapa II in the Chicama Valley to show that the physical components of the site's layout and the spatial patterns of artifact distribution relate to temporal and socio-political divisions that have their roots in long-standing ideas in Andean thought. Overall, this study shows that through careful evaluation some Quechua and Aymara concepts, namelytinku—or two parts coming together to make a whole—is relevant to the Moche worldview. This concept is manifest through canals uniting and dividing physical space, both socio-politically and temporally. Liquids running through the canals ensure the well-being and energetic flow of Moche society.

Older adults (age ≥ 65 years) are the fastest growing age group undergoing lung transplantation. Further, international consensus document for the selection of lung transplant candidates no longer suggest a fixed upper age limit. Although carefully selected older adults can derive great benefit, understanding which older adults will do well after transplant with improved survival and health-related qualiy of life is key to informed decision-making. Herein, we review the epidemiology of aging in lung transplantation and its impact on outcomes, highlight selected physiological measures that may be informative when evaluating and managing older lung transplant patients, and identify directions for future research.In general, listing and transplanting older, sicker patients has contributed to worse clinical outcomes and greater healthcare use. Emerging evidence suggest that measures of physiological age, such as frailty, body composition, and neurocognitive and psychosocial function, may better identify risk for poor transplant outcomes than chronlogical age.The evidence base to inform transplant decision-making and improvements in care for older adults is small but growing. Multipronged efforts at the intersection of aging and lung transplantation are needed to improve the clinical and patient centered outcomes for this large and growing cohort of patients. Future research should focus on identifying novel and ideally modifiable risk factors for poor outcomes specific to older adults, better approaches to measuring physiological aging (e.g., frailty, body composition, neurocognitive and psychosocial function), and the underlying mechanisms of physiological aging. Finally, interventions that can improve clinical and patient centered outcomes for older adults are needed.

William Hasker has been one of the most trenchant and insightful critics of the revival of Molinism. He has focused on the “freedom problem”, a set of challenges designed to show that Molinism does not secure a place for genuinely free human action (Hasker 1986, 1995, 1999, 2000a, 2000b, 2011). These challenges focus on a key element in the Molinist story: the counterfactual (or subjunctive) conditionals of creaturely freedom. According to Molinism, these conditionals have contingent truth-values that are knowable to God prior to His decision of what world to actualize. This divine “middle knowledge” is supposed to enable God to execute a detailed plan for world history without any loss of creaturely freedom. Hasker has argued that this middle knowledge nonetheless deprives us of the power to do otherwise than we do, a crucial element in human freedom and responsibility. I hope to accomplish three things in this paper. First, I want to step back a bit and explore the nature of the conditionals of creaturely free decision-making (the CCFs), bringing out some of the difficulties in delimiting their scope and nature. Second, I will explore the implications of different answers to an important question that has not been addressed in the literature: whether we have counterfactual power over the conditionals of divine freedom. And, third, I would like to recommend to Molinists a revision that offers a solution to the freedom problem.

Research Highlight: Valenzuela-Sánchez, A., Azat, C., Cunningham, A. A., Delgado, S., Bacigalupe, L. D., Beltrand, J., Serrano, J. M., Sentenac, H., Haddow, N., Toledo, V., Schmidt, B. R.,Cayuela, H. (2022). Interpopulation differences in male reproductive effort drive the population dynamics of a host exposed to an emerging fungal pathogen. Journal of Animal Ecology, 00, 1- 12. https://doi.org/10.1111/1365-2656.13603. Understanding the nuances of population persistence in the face of a stressor can help predict extinction risk and guide conservation actions. However, the exact mechanisms driving population stability may not always be known. In this paper, Valenzuela-Sánchez et al. (2022) integrate long-term mark-recapture data, focal measurements of reproductive effort, a population matrix model and inferences on life-history variation to reveal differences in demographic response to disease in a susceptible frog species (Rhinoderma darwinii). Valenzuela-Sánchez et al. found that demographic compensation via recruitment explained the positive population growth rate in their high disease prevalence population whereas the low disease prevalence population did not compensate and thus had decreasing population growth. Compensatory recruitment was likely due to the high probability of males brooding, and the high number of brooded larvae in the high prevalence population compared to low prevalence and disease-free populations. Valenzuela-Sánchez et al. also document faster generation times in the high prevalence population, which may indicate a faster life history that may be contributing to the population's ability to compensate for reduced survival. Lastly, the authors find a positive relationship between disease prevalence and the proportion of juveniles in a given population that suggest that there may be a threshold for disease prevalence that triggers increased reproductive effort. Altogether, their study provides novel support for increased reproductive effort as the pathway for compensatory recruitment leading to increasing population growth despite strong negative effects of disease on adult survival. Their results also caution the overgeneralization of the effects of stressors (e.g. disease) on population dynamics, where context-dependent responses may differ among host populations of a given species.

To improve safe sleep compliance in a newborn nursery (NN) and neonatal intensive care unit (NICU) to 80% in 1 year.Prospective quality improvement study of infants admitted to a NN and NICU. Interventions were targeted at parent education, staff education, and system processes.Compliance with safe sleep improved to 80% in both units. Tracking of process measures revealed NICU parents received safe sleep education 98-100% of the time. No change was observed in the balancing measures. Transfers from the NN to the NICU for temperature instability did not increase. Parent satisfaction with discharge preparedness did not change (98.2% prior to and 99.6% after).We achieved improved compliance with safe sleep practices in our NN and NICU through education of staff and parents and improved system processes. We believe this will translate to improved safe sleep practices used by parents at home.

Volumetric muscle loss is a debilitating injury that can leave patients with long-lasting or permanent structural and functional deficits. With clinical treatments failing to address these shortcomings, there is a great need for tissue-engineered therapies to promote skeletal muscle regeneration. In this study, we aim to assess the potential for electrospun decellularized skeletal muscle extracellular matrix (dECM) to promote skeletal muscle regeneration in a rat partial thickness tibialis anterior defect model. Aligned electrospun scaffolds with varying degrees of crosslinking density were implanted into the defect site and compared to an empty defect control. After 8 weeks, muscles were harvested, weighed, and cellular and morphological analyses were performed via histology and immunohistochemistry. Cell infiltration, angiogenesis, and myogenesis were observed in the defect site in both dECM groups. However, favorable mechanical properties and slower degradation kinetics resulted in greater support of tissue remodeling in the more crosslinked scaffolds and preservation of existing myofiber area in both dECM groups compared to the empty defect control. More sustained release of pro-regenerative degradation products also promoted greater myofiber formation in the defect site. This study allowed for a greater understanding of how electrospun skeletal muscle scaffolds interact with existing skeletal muscle and can inform their potential as a therapy in a wide variety of soft tissue applications.

Bioventing is a remediation technology that enhances aerobic biodegradation of petroleum-affected soil in the vadose zone by introducing oxygen to the subsurface. Bioventing was historically considered effective for decreasing petroleum hydrocarbons concentrations in soil but discounted for sites where mobile light non-aqueous phase liquid (LNAPL) accumulated in wells. While the science behind bioventing has not changed, the conceptual understanding of LNAPL depletion processes and framework for evaluating the efficacy of LNAPL remediation technologies has changed markedly since the 1990s. This shift leads to a new perspective on the utility and effectiveness of bioventing compared to other LNAPL remedial alternatives. A case study is used to illustrate that mass depletion by bioventing often outperforms hydraulic recovery over time. Biodegradation processes enhanced by bioventing deplete LNAPL constituents in mobile and residual LNAPL in the LNAPL smear zone, which means that bioventing can address a larger mass of LNAPL and may induce a beneficial composition change. Hydraulic LNAPL recovery technologies only access the mobile LNAPL and do not induce a composition change. Furthermore, for low LNAPL recoverability (transmissivity), bioventing typically uses less energy and produces less waste per unit mass of hydrocarbon removed than hydraulic recovery, making bioventing a more sustainable remedial technology.

This article provides an overview of critical issues regarding music in archives.

Many of the women currently incarcerated in state prisons are mothers. They have similar programming needs as other women in prison, including education, work, counseling, and drug treatment, yet t...

BackgroundFemales routinely receive bupivacaine for obstetric and regional anesthesia. An accidental overdose of bupivacaine can result in cardiotoxicity and cardiac arrest. Intralipid (ILP) rescues bupivacaine-induced cardiotoxicity in male rats. However, bupivacaine cardiotoxicity and ILP rescue have not been studied in non-pregnant and late-pregnant female rats. Here, we tested the hypothesis that an appropriate dose of ILP would rescue non-pregnant and late-pregnant rats from bupivacaine-induced cardiotoxicity.MethodsNon-pregnant (n = 6) and late-pregnant (n = 7) female rats received intravenous bupivacaine (10-mg/kg bolus) to induce asystole. Resuscitation with 20% ILP (5-ml/kg actual body weight, single bolus, and 0.5-ml/kg/min maintenance) and chest compressions were continued for 10-min. Serial heart rate (HR), left ventricular ejection-fraction (LVEF%), and LV-fractional shortening (LVFS%) were recorded at baseline and 10-min after bupivacaine-induced cardiac arrest. Data are mean ± SD followed by 95% CI. P-values < 0.05 were considered statistically significant.ResultsAll rats developed cardiac arrest within a few seconds after bupivacaine. All non-pregnant rats were successfully rescued by ILP, with a HR of 280 ± 32 bpm at baseline vs. 212 ± 18 bpm at 10-min post ILP (p < 0.01), LVEF of 70 ± 6% vs. 68 ± 5% (p = ns), and LVFS of 41 ± 5% vs. 39 ± 4% (p = ns). Interestingly, 6 out of 7 late-pregnant rats did not recover with ILP. Baseline HR, LVEF and LVFS for late-pregnant rats were 330 ± 40 bpm, 66 ± 5% and 38 ± 4%, respectively. At 10-min post ILP, the HR, LVEF, and LVFS were 39 ± 102 bpm (p < 0.0001), 8 ± 22% (p < 0.0001), and 5 ± 12% (p < 0.001), respectively.ConclusionsILP successfully rescued bupivacaine-induced cardiac arrest in non-pregnant rats, but failed to rescue late-pregnant rats.

The divine purpose theory (DPT)—according to which that human life is meaningful to the extent that it fulfills some purpose or plan to which God has directed us—encounters well-known Euthyphro problems. Some theists attempt to avoid these problems by appealing to God’s essential goodness, à la the modified divine command theory (DCT) of Adams and Alston. However, recent criticisms of the modified DCT show its conception of God’s goodness to be incoherent; and these criticisms can be shown to present an analogous set of problems for the DPT. Further, the argument can be extended to any account of meaningfulness according to which the value of what humans do can only be conferred by God. Thus, it would seem that there is no tenable version of the view that meaningfulness is conferred on human life by some act or attitude of God’s.

This study investigated the chondrogenic activity of encapsulated mesenchymal stem cells (MSCs) and articular chondrocytes (ACs) and its impact on the mechanical properties of injectable poly(N-isopropylacrylamide)-based dual-network hydrogels loaded with poly(L-lysine) (PLL). To this effect, an ex vivo study model was employed to assess the behavior of the injected hydrogels - specifically, their surface stiffness and integration strength with the surrounding cartilage. The highest chondrogenic activity was observed from AC-encapsulated hydrogels, while the effect of PLL on MSC chondrogenesis was not apparent from biochemical analyses. Mechanical testing showed that there were no significant differences in either surface stiffness or integration strength among the different study groups. Altogether, the results suggest that the ex vivo model can allow further understanding of the relationship between biochemical changes within the hydrogel and their impact on the hydrogel's mechanical properties. This article is protected by copyright. All rights reserved.

Author(s): Koons, Andrew; Amaducci, Alexandra M.; Katz, Kenneth D. | Abstract: Introduction: Metformin is a biguanide used to treat diabetes mellitus (DM). Metformin-associated lactic acidosis (MALA) carries a high mortality and can occur in patients with renal failure from drug bioaccumulation. Reversible vision loss is a highly unusual, rarely reported complication of MALA. We present a case of a patient whose serum metformin concentration was unusually high and associated with vision loss.Case Report: A 60-year-old woman presented to an outside hospital emergency department with acute vision loss after being found at home confused, somnolent, and hypoglycemic, having last being seen normal two days prior. She reported vomiting and diarrhea during that time and a recently treated urinary tract infection. The visual loss resolved with continuous renal replacement therapy.Conclusion: This novel case of a patient with Type II DM prescribed metformin and insulin who developed reversible vision loss while suffering from MALA highlights the potential for vision loss in association with MALA.

Hemorrhage is a leading cause of death following traumatic injuries in the United States. Much of the previous work in assessing the physiology and pathophysiology underlying blood loss has focused on descriptive measures of hemodynamic responses such as blood pressure, cardiac output, stroke volume, heart rate, and vascular resistance as indicators of changes in organ perfusion. More recent work has shifted the focus toward understanding mechanisms of compensation for reduced systemic delivery and cellular utilization of oxygen as a more comprehensive approach to understanding the complex physiologic changes that occur following and during blood loss. In this article, we begin with applying dimensional analysis for comparison of animal models, and progress to descriptions of various physiological consequences of hemorrhage. We then introduce the complementary side of compensation by detailing the complexity and integration of various compensatory mechanisms that are activated from the initiation of hemorrhage and serve to maintain adequate vital organ perfusion and hemodynamic stability in the scenario of reduced systemic delivery of oxygen until the onset of hemodynamic decompensation. New data are introduced that challenge legacy concepts related to mechanisms that underlie baroreflex functions and provide novel insights into the measurement of the integrated response of compensation to central hypovolemia known as the compensatory reserve. The impact of demographic and environmental factors on tolerance to hemorrhage is also reviewed. Finally, we describe how understanding the physiology of compensation can be translated to applications for early assessment of the clinical status and accurate triage of hypovolemic and hypotensive patients. © 2021 American Physiological Society. Compr Physiol 11:1531-1574, 2021.

Background The prevalence of burnout and depressive symptoms is high among physician trainees. Research Question What is the burden of burnout and depressive symptoms among fellows training in pulmonary and critical care medicine (PCCM) and what are associated individual fellow, program, and institutional characteristics? Study Design and Methods We conducted a cross-sectional electronic survey of fellows enrolled in pulmonary, PCCM, and critical care medicine training programs in the United States to assess burnout and depressive symptoms. Burnout symptoms were measured using the Maslach Burnout Index two-item measure. The two-item Primary Care Evaluation of Mental Disorders Procedure was used to screen for depressive symptoms. For each of the two outcomes (burnout and depressive symptoms), we constructed three multivariate logistic regression models to assess individual fellow characteristics, program structure, and institutional polices associated with either burnout or depressive symptoms. Results Five hundred two of the 976 fellows who received the survey completed it—including both outcome measures—giving a response rate of 51%. Fifty percent of fellows showed positive results for either burnout or depressive symptoms, with 41% showing positive results for depressive symptoms, 32% showing positive results for burnout, and 23% showing positive results for both. Reporting a coverage system in the case of personal illness or emergency (adjusted OR [aOR], 0.44; 95% CI, 0.26-0.73) and access to mental health services (aOR, 0.14; 95% CI, 0.04-0.47) were associated with lower odds of burnout. Financial concern was associated with higher odds of depressive symptoms (aOR, 1.13; 95% CI, 1.05-1.22). Working more than 70 hours in an average clinical week and the burdens of electronic health record (EHR) documentation were associated with a higher odds of both burnout and depressive symptoms. Interpretation Given the high prevalence of burnout and depressive symptoms among fellows training in PCCM, an urgent need exists to identify solutions that address this public health crisis. Strategies such as providing an easily accessible coverage system, access to mental health resources, reducing EHR burden, addressing work hours, and addressing financial concerns among trainees may help to reduce burnout or depressive symptoms and should be studied further by the graduate medical education community.