Recycling the Petrodollar: Current Problem, Future Opportunity

Have the U.S. balance of payments position and the value of our currency in relation to other national currencies been weakened by the increased petroleum prices? The answer is not self-evident. While increased imported oil prices have undoubtedly caused certain difficulties in the U.S. economy and in the BOP, it is entirely possible that over the long-term this situation could be economically advantageous to the United States. This paper seeks to illustrate the multifaceted dimension of currency movements and how money moves through the world\u27s economy

Impact of Human Presence and Visual Access on Barking Behavior in Shelter Dogs

Shelters can be stressful for dogs due to lack of predictability and control, social isolation, and busy environments. Providing dogs with more social opportunities and environmental predictability may improve their welfare. Barking may indicate stress and contribute to noise levels that are harmful to dogs and people. We investigated the impact of human presence and line of sight on barking. We manipulated line of sight by partially removing a crate barrier to allow the dogs visual access to other dogs and a better view of the room. We collected data on barking on 17 focal dogs as well as overall barking in the room during pre-treatment (no visual access), treatment (visual access), and post-treatment (no visual access) and noted if a person other than the observer was in the room. We found that in-room barking was significantly higher when a person was in the room (Wilcoxon Signed Ranks Test, Z= -4.048, p \u3c .001). Based on these results, shelters should consider limiting the human activity in the room to reduce noise levels. Since barking did not significantly increase with the addition of visual access, shelters may also consider providing the dogs visual access as a way to allow beneficial social interaction

Provably and Efficiently Approximating Near-cliques using the Tur\'an Shadow: PEANUTS

Clique and near-clique counts are important graph properties with applications in graph generation, graph modeling, graph analytics, community detection among others. They are the archetypal examples of dense subgraphs. While there are several different definitions of near-cliques, most of them share the attribute that they are cliques that are missing a small number of edges. Clique counting is itself considered a challenging problem. Counting near-cliques is significantly harder more so since the search space for near-cliques is orders of magnitude larger than that of cliques. We give a formulation of a near-clique as a clique that is missing a constant number of edges. We exploit the fact that a near-clique contains a smaller clique, and use techniques for clique sampling to count near-cliques. This method allows us to count near-cliques with 1 or 2 missing edges, in graphs with tens of millions of edges. To the best of our knowledge, there was no known efficient method for this problem, and we obtain a 10x - 100x speedup over existing algorithms for counting near-cliques. Our main technique is a space-efficient adaptation of the Tur\'an Shadow sampling approach, recently introduced by Jain and Seshadhri (WWW 2017). This approach constructs a large recursion tree (called the Tur\'an Shadow) that represents cliques in a graph. We design a novel algorithm that builds an estimator for near-cliques, using an online, compact construction of the Tur\'an Shadow.Comment: The Web Conference, 2020 (WWW

Investment in Africa's manufacturing sector: A four country panel data analysis

Firm-level data for the manufacturing sector in Africa, presented in this paper, shows very low levels of investment. A positive effect from profits onto investment is identified in a flexible accelerator specification of the investment function controlling for firm fixed effects. There is evidence that this effect is confined to smaller firms. A comparison with other studies shows that, for such firms, the profit effect is much smaller in Africa than in other countries. Reasons for the relative insensitivity of investment to profits in African firms are suggested.firm investment, liquidity constraints, African manufacturing

Influence of UV Treatment on the Food Safety Status of a Model Aquaponic System

Few microbial studies in aquaponics, a growing trend in food production, have been conducted to determine food safety status. The aim of this study was to determine the food safety status and the effectiveness of ultraviolet treatment (15 W, luminous flux of 900 lm) as a food safety intervention in reducing the microbial loads of the water system in a model aquaponic unit growing lettuce, basil, and barramundi (Australian Sea Bass). Sweet basil, bibb lettuce, water samples, and fish swabs were collected throughout the 118-day production period, and microbial analysis was conducted in triplicate for the presence of E. coli O157:H7, Salmonella spp., and the prevalence of aerobic plate counts (APC), coliforms, and fecal coliforms in these systems. Absence of foodborne pathogens was confirmed using ELISA technology and enumeration through petrifilms (coliform/E. coli). A significant increase was observed in aerobic plate counts over the trial period (1 to 3 log10 CFU·mL−1) in the presence and absence of UV (p \u3e 0.05). Ultraviolet treatment did not significantly reduce the APC or coliform counts when compared to the control system samples. Future work should focus on improving the unit design, the evaluation of bio-solid filtration, and other food safety interventions

#6 - Implications of Visual Social Access on the Welfare and Behavior of Shelter Dogs

Given the large number of dogs housed in animal shelters each year, it is important to consider how the shelter environment impacts dog welfare. The shelter environment is stressful due to factors such as excessive noise, lack of predictability and control, and social isolation. Social isolation in shelter dogs has been found to increase abnormal behavior and aggression and lead to poorer adoption outcomes. While social housing is ideal, it requires resources not available to all shelters. Providing visual access to other dogs is a relatively easy environmental modification that increases social opportunities and allows for more predictability and control over the environment, potentially improving welfare. To investigate the impact of visual access on the behavior of dogs, we used a within-subject design, conducting 5-min focal observations four times weekly before, during, and after visual access was provided by partially removing a barrier between crates at a suburban dog shelter. Our preliminary analysis of 17 subjects using non-parametric Friedman’s Tests (alpha = .05) found no significant difference between phases in regard to anxiety behaviors (χ2 (2) = .50, p = .78), frustration behaviors (χ2 (2) = .51, p = .77), time spent in the front of the crate (χ2 (2) = 4.50, p = .11), self-directed behaviors (χ2 (2) = 1.86, p = .40), resting behaviors (χ2 (2) = 4.59, p = .10), or vocalizations (χ2 (2) = 4.59, p= .10). The absence of an increase in vocalizations during visual access may encourage shelters to implement this change. However, the lack of a decrease in anxiety or frustration behaviors may indicate that visual access alone is insufficient for providing welfare benefits and that shelters should prioritize increasing social contact in dogs through playgroups or group housing. Keywords: shelter dog, animal welfare, barking, social housing, visual access, social contact, anxiety, environmental predictability, choic

Implications of Visual Social Access on the Welfare and Behavior of Shelter Dogs

Animal shelter environments have many stressful factors that impact the welfare of shelter dogs, such as lack of predictability and control, and social isolation. Social isolation has been found to increase abnormal behavior and lead to poorer adoption outcomes. Providing visual access to shelter dogs is a relatively easy environmental modification that increases social opportunities and allows for more predictability and control over the environment, potentially improving welfare. To investigate the impact of visual access on the behavior of dogs, we used a within-subject design, conducting 5-min focal observations four times weekly before, during, and after visual access was provided by partially removing a barrier between crates at a suburban dog shelter. Our preliminary analysis of 17 subjects using non-parametric Friedman’s Tests (alpha = .05) found no significant difference between phases in regard to anxiety behaviors (χ2 (2) = .50, p = .78), frustration behaviors (χ2 (2) = .51, p = .77), time spent in the front of the crate (χ2 (2) = 4.50, p = .11), self-directed behaviors (χ2 (2) = 1.86, p = .40), resting behaviors (χ2 (2) = 4.59, p = .10), or vocalizations (χ2 (2) = 4.59, p = .10). The absence of an increase in vocalizations during visual access may encourage shelters to implement this change. However, the lack of a decrease in anxiety or frustration behaviors may indicate that visual access alone is insufficient for providing welfare benefits and that shelters should prioritize increasing social contact in dogs through playgroups or group housing

Investigation of API 8 Round Casing Connection Performance- Part III: Sealability and Torque

The performance of the API LT&C8 Round casing connection is investigated using 7-in.-29-lbift Introduction A 7-in.-29-lb/ft pipe size is used to investigate the performance of the API LT&C 8 Round (8R) casing connection. Part I [1], compared stress results determined from unthreaded and threaded finite element models, test results from strain gages, and hand calculations using strength of material equations. These comparisons showed the finite element modeling to be valid. Part II [2], dealt with the effects of thread tapers and external loads on pin and coupling hoop stresses. It also investigated maximum assembly interference based on an assumed criteria. Part III, is concerned with connection sealability based on the assumption that the contact pressure in the mated surfaces must equal or exceed the fluid pressure being contained. Of particular interest is the effects of thread taper, tension and internal pressure, with tension being the greatest unknown influence on leak tightness. Variations in torque are also investigated from the same forces used to evaluate sealability

Oxygen tension, H2S, and NO bioavailability:is there an interaction?

Molecular oxygen (O2) is an essential component for survival and development. Variation in O2 levels leads to changes in molecular signaling and ultimately affects the physiological functions of many organisms. Nitric oxide (NO) and hydrogen sulfide (H2S) are two gaseous cellular signaling molecules that play key roles in several physiological functions involved in maintaining vascular homeostasis including vasodilation, anti-inflammation, and vascular growth. Apart from the aforementioned functions, NO and H2S are believed to mediate hypoxic responses and serve as O2 chemosensors in biological systems. In this literature review, we briefly discuss NO and H2S and their roles during hypoxia

Placenta-specific methylation of the vitamin D 24-hydroxylase gene: implications for feedback autoregulation of active vitamin D levels at the fetomaternal interface

Plasma concentrations of biologically active vitamin D (1,25- (OH)2D) are tightly controlled via feedback regulation of renal 1-hydroxylase (CYP27B1; positive) and 24-hydroxylase (CYP24A1; catabolic) enzymes. In pregnancy, this regulation is uncoupled, and 1,25-(OH)2D levels are significantly elevated, suggesting a role in pregnancy progression. Epigenetic regulation of CYP27B1 and CYP24A1 has previously been described in cell and animal models, and despite emerging evidence for a critical role of epigenetics in placentation generally, little is known about the regulation of enzymes modulating vitamin D homeostasis at the fetomaternal interface. In this study, we investigated the methylation status of genes regulating vitamin D bioavailability and activity in the placenta. No methylation of the VDR (vitamin D receptor) and CYP27B1 genes was found in any placental tissues. In contrast, the CYP24A1 gene is methylated in human placenta, purified cytotrophoblasts, and primary and cultured chorionic villus sampling tissue. No methylation was detected in any somatic human tissue tested. Methylation was also evident in marmoset and mouse placental tissue. All three genes were hypermethylated in choriocarcinoma cell lines, highlighting the role of vitaminDderegulation in this cancer. Gene expression analysis confirmed a reduced capacity for CYP24A1 induction with promoter methylation in primary cells and in vitro reporter analysis demonstrated that promoter methylation directly down-regulates basal promoter activity and abolishes vitamin D-mediated feedback activation. This study strongly suggests that epigenetic decoupling of vitamin D feedback catabolism plays an important role in maximizing active vitamin D bioavailability at the fetomaternal interface