Cardiorespiratory and Metabolic Responses to Low-Intensity Blood-Flow Restricted Running

Low-intensity (LI) aerobic exercise with blood-flow restriction (BFR) increases heart rate (HR), oxygen consumption (VO2), and ratings of perceived exertion (RPE), sometimes to similar levels as high-intensity (HI) exercise. Distance runners may benefit from LI-BFR running in periods of reduced volume or intensity, possibly due to injury. PURPOSE: To compare HR, VO2, blood lactate (BLa), and RPE during LI-BFR running and HI running without BFR. METHODS: Fifteen female distance runners (age 23+4yrs, height 1.67+0.50m, body mass 57.6+5.7kg, VO2max 51.0+4.5mL•kg-1•min-1) completed three randomized 12-minute running conditions: LI control (40% VO2max), HI (80% VO2max), and LI-BFR (40% VO2max). VO2, HR, and RPE were measured at rest, and every 3-minutes. BLa was measured at rest, immediately-post (ImmPost), and 3-minutes post-exercise (3minPost). RESULTS: VO2 remained steady among each condition (p=0.075,ηp2=0.155). The average VO2 differed between the conditions (p\u3c0.001), as HI (39.4+3.9mL•kg-1•min-1) \u3e LI-BFR (25.3+2.6mL•kg-1•min-1) \u3e LI (22.5+3.1mL•kg-1•min-1). HR increased at the onset of exercise and differed between the conditions (p\u3c0.001,ηp2=0.745). The average HR for HI, LI-BFR, and LI were 166+8bpm, 142+13bpm, and 124+11bpm, respectively. BLa was similar in HI and LI-BFR ImmPost and 3minPost (p\u3e0.05), and both were higher than LI (p\u3c0.017). Average RPE in the HI and LI-BFR conditions were similar (p=0.236). CONCLUSION: HI elicits greater VO2 and HR responses than LI-BFR running, suggesting that HI would result in more robust long-term training responses. However, if one cannot engage in HI running because of injury and rehabilitation, LI-BFR running could be a feasible temporary alternative

Using participatory research to expand the customer base of farmers markets

Direct-to-consumer sales (DTC) through farmers markets, CSAs, and urban farm stands is an important venue for bringing fresh, nutritious, and regional food to urban consumers and creating economic and social linkages between urban and peri-urban farms. However, many urban consumers who use government food programs have limited access to DTC markets. Farmers Market LIFE (Local Incentives for Food and Economy) seeks to expand the customer base of farmers market shoppers in Sonoma County, California, through the acceptance of SNAP (the Supplemental Nutrition Assistance Program) and Market Match, a dollar-for-dollar nutrition incentive program that makes farmers markets more economically accessible to low-income shoppers while also increasing overall sales for farmers’ market vendors. We explore the use of “environmental scans” an innovative research instrument used at farmers’ markets to identify social, cultural, linguistic, behavioral and economic obstacles and opportunities for low-income consumers and people of color to shop at farmers’ markets. Community partners co-designed and gathered data about selected farmers markets using environmental scans in fall 2019. This methodology has proved effective in providing insight into farmers’ market dynamics including potential barriers and solutions to make farmers’ markets more accessible and inviting to SNAP customers and people of color. We share results of this tool as a method that others interested in community-engaged research may want to use to investigate their own unique farmers’ market settings and to illustrate the nature of findings from our application of the tool in Sonoma County, California, in 2019

Modelling chemotherapy resistance in palliation and failed cure

The goal of palliative cancer chemotherapy treatment is to prolong survival and improve quality of life when tumour eradication is not feasible. Chemotherapy protocol design is considered in this context using a simple, robust, model of advanced tumour growth with Gompertzian dynamics, taking into account the effects of drug resistance. It is predicted that reduced chemotherapy protocols can readily lead to improved survival times due to the effects of competition between resistant and sensitive tumour cells. Very early palliation is also predicted to quickly yield near total tumour resistance and thus decrease survival duration. Finally, our simulations indicate that failed curative attempts using dose densification, a common protocol escalation strategy, can reduce survival times

Phamerator: a bioinformatic tool for comparative bacteriophage genomics

Background: Bacteriophage genomes have mosaic architectures and are replete with small open reading frames of unknown function, presenting challenges in their annotation, comparative analysis, and representation.Results: We describe here a bioinformatic tool, Phamerator, that assorts protein-coding genes into phamilies of related sequences using pairwise comparisons to generate a database of gene relationships. This database is used to generate genome maps of multiple phages that incorporate nucleotide and amino acid sequence relationships, as well as genes containing conserved domains. Phamerator also generates phamily circle representations of gene phamilies, facilitating analysis of the different evolutionary histories of individual genes that migrate through phage populations by horizontal genetic exchange.Conclusions: Phamerator represents a useful tool for comparative genomic analysis and comparative representations of bacteriophage genomes. © 2011 Cresawn et al; licensee BioMed Central Ltd

Genomes and Characterization of Phages Bcep22 and BcepIL02, Founders of a Novel Phage Type in Burkholderia cenocepacia

Within the Burkholderia cepacia complex, B. cenocepacia is the most common species associated with aggressive infections in the lungs of cystic fibrosis patients, causing disease that is often refractive to treatment by antibiotics. Phage therapy may be a potential alternative form of treatment for these infections. Here we describe the genome of the previously described therapeutic B. cenocepacia podophage BcepIL02 and its close relative, Bcep22. Phage Bcep22 was found to contain a circularly permuted genome of 63,882 bp containing 77 genes; BcepIL02 was found to be 62,714 bp and contains 76 predicted genes. Major virion-associated proteins were identified by proteomic analysis. We propose that these phages comprise the founding members of a novel podophage lineage, the Bcep22-like phages. Among the interesting features of these phages are a series of tandemly repeated putative tail fiber genes that are similar to each other and also to one or more such genes in the other phages. Both phages also contain an extremely large (ca. 4,600-amino-acid), virion-associated, multidomain protein that accounts for over 20% of the phages' coding capacity, is widely distributed among other bacterial and phage genomes, and may be involved in facilitating DNA entry in both phage and other mobile DNA elements. The phages, which were previously presumed to be virulent, show evidence of a temperate lifestyle but are apparently unable to form stable lysogens in their hosts. This ambiguity complicates determination of a phage lifestyle, a key consideration in the selection of therapeutic phages

Multi-messenger searches via IceCube’s high-energy neutrinos and gravitational-wave detections of LIGO/Virgo

We summarize initial results for high-energy neutrino counterpart searches coinciding with gravitational-wave events in LIGO/Virgo\u27s GWTC-2 catalog using IceCube\u27s neutrino triggers. We did not find any statistically significant high-energy neutrino counterpart and derived upper limits on the time-integrated neutrino emission on Earth as well as the isotropic equivalent energy emitted in high-energy neutrinos for each event

In-situ estimation of ice crystal properties at the South Pole using LED calibration data from the IceCube Neutrino Observatory

The IceCube Neutrino Observatory instruments about 1 km3 of deep, glacial ice at the geographic South Pole using 5160 photomultipliers to detect Cherenkov light emitted by charged relativistic particles. A unexpected light propagation effect observed by the experiment is an anisotropic attenuation, which is aligned with the local flow direction of the ice. Birefringent light propagation has been examined as a possible explanation for this effect. The predictions of a first-principles birefringence model developed for this purpose, in particular curved light trajectories resulting from asymmetric diffusion, provide a qualitatively good match to the main features of the data. This in turn allows us to deduce ice crystal properties. Since the wavelength of the detected light is short compared to the crystal size, these crystal properties do not only include the crystal orientation fabric, but also the average crystal size and shape, as a function of depth. By adding small empirical corrections to this first-principles model, a quantitatively accurate description of the optical properties of the IceCube glacial ice is obtained. In this paper, we present the experimental signature of ice optical anisotropy observed in IceCube LED calibration data, the theory and parametrization of the birefringence effect, the fitting procedures of these parameterizations to experimental data as well as the inferred crystal properties.</p