Karst aquifer discharge response to rainfall interpreted as anomalous transport

The discharge measured in karst springs is known to exhibit distinctive long tails during recession times following distinct short-duration discharge peaks. The long-tailed behavior is generally attributed to the occurrence of tortuous, ramified flow paths that develop in the underground structure of karst systems. Modeling the discharge behavior poses unique difficulties because of the poorly delineated flow path geometry and generally scarce information on the hydraulic properties of catchment-scale systems. In a different context, modeling of long-tailed behavior has been addressed in studies of chemical transport. Here, an adaptation of a continuous time random walk–particle tracking (CTRW-PT) framework for anomalous transport is proposed, which offers a robust means to quantify long-tailed breakthrough curves that often arise during the transport of chemical species under various flow scenarios. A theoretical analogy is first established between partially water-saturated karst flow, characterized by temporally varying water storage, and chemical transport involving the accumulation and release of a chemical tracer. This analogy is then used to develop and implement a CTRW-PT model. Application of this numerical model to the examination of 3 years of summer rainfall and discharge data from a karst aquifer system – the Disnergschroef high-alpine site in the Austrian Alps – is shown to yield robust fits between modeled and measured discharge values. In particular, the analysis underscores the predominance of slow diffusive flow over rapid conduit flow. The study affirms the analogy between partially saturated karst flow and chemical transport, exemplifying the compatibility of the CTRW-PT model for this purpose. Within the specific context of the Disnergschroef karst system, these findings highlight the predominance of slow diffusive flow over rapid conduit flow. The agreement between measured and simulated data supports the proposed analogy between partially saturated karst flow and chemical transport; it also highlights the potential ability of the anomalous transport framework to further enhance modeling of flow and transport in karst systems

The effects of moderate prenatal alcohol exposure on the organization of exploratory behavior by adult female rats

A large body of research has indicated that moderate Prenatal Alcohol Exposure (PAE - 60 mg/dl peak BAC) can produce impairments on cognitive processes, such as spatial learning and memory. The neurobiological basis of these impairments is poorly understood but is frequently linked to alterations in hippocampal functioning. Although the hippocampus has a central role in learning and memory, damage to the hippocampus can also produce impairments in locomotor and exploratory behaviors by rodents (reviewed in Thompson et al., 2018). Rodent exploratory behavior is organized around home bases, which serves as central points of attraction from which rats and mice organize their exploratory trips into the remaining environment. We are unaware of studies investigating the relationship between moderate prenatal alcohol exposure and exploratory behavior. Thus, in the present study, we tested adult female rats in two experiments where they were allowed to freely explore a circular open field for ~30min. Here, we report that, with respect to home base behavior, exploratory movements were largely intact in rats exposed to alcohol prenatally. Specifically, animals rapidly established home bases within 5min of the beginning of testing and the bases were established in one or two locations in the environment. They made exploratory trips away and back to the home base and made several stops at this location along with bouts of grooming behavior. The results are discussed with respect to theories of hippocampal function and the impact of moderate prenatal alcohol on spatial behavior

Laboratory Investigation of Skid Resistance for Steel Slag Utilization as Chip Seal

Slag as waste material of steel-making process has similar characteristics with aggregate that has been widely used in pavement construction. The use of slag as chip seal aggregate to provide skid resistance needs to be analyzed. In this laboratory study, the chip seal samples are made using steel slag and natural aggregate. The bonding materials used are asphalt and epoxy resin. Skid resistance tests for all chip seal samples and also hot rolled sheet pavement without chip seal application are performed using the Portable British Pendulum Tester. The results show the variations of chip seal aggregate weight are inconsistent. The natural aggregate used as chip seal material could produce high skid resistance value of 10.3% higher than that using steel slag. Also the skid resistance of chip seal with the ALD 3 mm are not significantly different with that of ALD 6 mm. Similar results occur on the skid resistance of chip seals using epoxy resin and asphalt

Role of senescence marker p16INK4a measured in peripheral blood T-lymphocytes in predicting length of hospital stay after coronary artery bypass surgery in older adults

Adults older than 65 years undergo more than 120,000 coronary artery bypass (CAB) procedures each year in the United States. Chronological age alone, though commonly used in prediction models of outcomes after CAB, does not alone reflect variability in aging process; thus, the risk of complications in older adults. We performed a prospective study to evaluate a relationship between senescence marker p16INK4a expression in peripheral blood T-lymphocytes (p16 levels in PBTLs) with aging and with perioperative outcomes in older CAB patients. We included 55 patients age 55 and older, who underwent CAB in Johns Hopkins Hospital between September 1st, 2010 and March 25th, 2013. Demographic, clinical and laboratory data following outline of the Society of Thoracic Surgeons data collection form was collected, and p16 mRNA levels in PBTLs were measured using Taqman® qRT-PCR. Associations between p16 mRNA levels in PBTLs with length of hospital stay, frailty status, p16 protein levels in the aortic and left internal mammary artery tissue, cerebral oxygen saturation, and augmentation index as a measure of vascular stiffness were measured using regression analyses. Length of hospital stay was the primary outcome of interest, and major organ morbidity, mortality, and discharge to a skilled nursing facility were secondary outcomes. In secondary analysis, we evaluated associations between p16 mRNA levels in PBTLs and interleukin-6 levels using regression analyses. Median age of enrolled patients was 63.5 years (range 56-81 years), they were predominantly male (74.55%), of Caucasian descent (85.45%). Median log2(p16 levels in PBTLs) were 4.71 (range 1.10-6.82). P16 levels in PBTLs were significantly associated with chronological age (mean difference 0.06 for each year increase in age, 95% CI 0.01-0.11) and interleukin 6 levels (mean difference 0.09 for each pg/ml increase in IL-6 levels, 95% CI 0.01-0.18). There were no significant associations with frailty status, augmentation index, cerebral oxygenation and p16 protein levels in blood vessels. Increasing p16 levels in PBTLs did not predict length of stay in the hospital (HR 1.10, 95% CI 0.87-1.40) or intensive care unit (HR 1.02, 95% CI 0.79-1.32). Additional evaluation of p16 levels in PBTLs as predictor of perioperative outcomes is required and should include additional markers of immune system aging as well as different outcomes after CAB in addition to length of hospital stay

Olfactory, Taste, and Photo Sensory Receptors in Non-sensory Organs: It Just Makes Sense

Sensory receptors that detect and respond to light, taste, and smell primarily belong to the G-protein-coupled receptor (GPCR) superfamily. In addition to their established roles in the nose, tongue, and eyes, these sensory GPCRs have been found in many ‘non-sensory' organs where they respond to different physicochemical stimuli, initiating signaling cascades in these extrasensory systems. For example, taste receptors in the airway, and photoreceptors in vascular smooth muscle cells, both cause smooth muscle relaxation when activated. In addition, olfactory receptors are present within the vascular system, where they play roles in angiogenesis as well as in modulating vascular tone. By better understanding the physiological and pathophysiological roles of sensory receptors in non-sensory organs, novel therapeutic agents can be developed targeting these receptors, ultimately leading to treatments for pathological conditions and potential cures for various disease states

Working in the Public Interest Law Conference

Entirely student organized, WIPI seeks to bring together eminent practitioners in their respective fields, students, and faculty to discuss practical approaches to lawyering which can best serve the poor. Practical methods of challenging poverty are often not covered in traditional law school courses. This conference seeks to remedy that and provide dynamic, creative ways to combat poverty through the vehicle of the law