Bacterial ‘immunity’ against bacteriophages

Vertebrate animals possess multiple anti-pathogen defenses. Individual mechanisms usually are differentiated into those that are immunologically adaptive vs. more “primitive” anti-pathogen phenomena described as innate responses. Here I frame defenses used by bacteria against bacteriophages as analogous to these animal immune functions. Included are numerous anti-phage defenses in addition to the adaptive immunity associated with CRISPR/cas systems. As these other anti-pathogen mechanisms are non-adaptive they can be described as making up an innate bacterial immunity. This exercise was undertaken in light of the recent excitement over the discovery that CRISPR/cas systems can serve, as noted, as a form of bacterial adaptive immunity. The broader goal, however, is to gain novel insight into bacterial defenses against phages by fitting these mechanisms into considerations of how multicellular organisms also defend themselves against pathogens. This commentary can be viewed in addition as a bid toward integrating these numerous bacterial anti-phage defenses into a more unified immunology

Leading basic skills education in North Carolina community college : successes and challenges

This qualitative study focuses on North Carolina community college basic skills departmental directors. In this study, interviews were the means to gather data and to give North Carolina community college basic skills directors a voice. The participants’ shared stories of their personal experiences in the execution of their duties as departmental directors revealed the successes and challenges that they face as they strive to make their programs effective and efficient, while they dispense educational services to the public they serve. The findings of this study reveal which policies, procedures, and practices that direct North Carolina basic skills educational programs are effective and which are not. Additionally, the findings of this study suggest implications for practice for North Carolina community college basic skills directors, North Carolina community college executive leadership teams, and for the North Carolina Community College System’s College and Career Readiness Division

Optimization of a PS2.M-based catalytic beacon in preparation for use as a device to explore mRNA secondary structures

The DNA oligonucleotide PS2.M has been previously reported to have nanomolar affinity for hemin. The PS2.M-hemin complex then exhibits peroxidase activity. It was predicted that this sequence could be used in a catalytic beacon to facilitate the development of a laboratory tool that would be effective at determining potential siRNA target sites. The PS2.M-based beacon used for this study forms a stem-loop structure that opens upon hybridization with a single-stranded target sequence. Once open, the PS2.M part of the beacon can fold, locking hemin within a three level planer arrangement. Once hemin is in place, the structure is catalytically active and can catalyze the oxidization of the chromogenic substrate 2,2,’-azino-bis (3-ethylebenzthiazoline-6-sulphonic acid) (ABTS) in the presence of hydrogen peroxide. Thus, binding of the beacon can be monitored with absorbance readings at 414 nm. Although molecular beacons with a stem-loop structure could potentially be used for this type of test, the cost would be prohibitively expensive for most labs. Molecular beacons cost over $300 a piece, and many of them would be needed to conduct an exploration for a suitable siRNA target site within an mRNA. In contrast, a PS2.M-based beacon would only cost approximately$12. In general, development and optimization of a PS2.M-based catalytic beacon could provide a more economical and improved means of establishing siRNA target site accessibility within an mRNA. It was concluded that K+ and Mg+ are required for folding of the PS2.M beacon. The substrate ABTS offered the highest absorbance values at a concentration of 3.2 mM. Also, H2O2 concentrations of 3.6 mM and an extension of the beacon stem by 10 nucleotides will result in reduced non-specific background absorbance activity

Attracting High School Boys To Interscholastic Football

It was the purpose of this study (1) to determine whether decreasing interest in interscholastic football at the secondary school level is a state-wide situation or a local problem, (2) to investigate the possible underlying causes for any waning interest, and (3) to make recommendations for improvements in the football program in order that it might attract and therefore benefit a greater number of students

Bastions Or Burdens? Assessing The Role Of Anglo-American Hospital Ships During The World Wars

Military historians rarely examine the evacuation of battlefield casualties. This project seeks to help remedy this deficiency by assessing the role of Anglo-American hospital ships during the First and Second World War. As far back as the eighteenth-century, military forces on both sides of the Atlantic have relied on hospital ships to provide a quick, efficient, safe, and comfortable means of evacuation for battlefield casualties. By observing their long-term development, and considering their performance in a number of battles around the world, this work argues that British and American hospital ships were a critically important presence in combat operations during the global conflicts of the early twentieth-century. At the same time, it also demonstrates that the era of the First and Second World represent the “golden age” of hospital ships. Following the Second World War, the ever-changing face of modern warfare led to a decline in both countries’ use of hospital ships. These ships, which had at one time represented bastions of safety and healing, ultimately became burdens to military powers who began to rely on other means of evacuating their casualties

Estimates Of Eastern Hellbender (Cryptobranchus Alleganiensis Alleganiensis) Occupancy And Detection Using Two Sampling Methods

Environmental DNA (eDNA) is a non-invasive survey method that is an increasingly popular alternative for detecting rare aquatic species. Although recent studies have demonstrated the efficacy of eDNA in detecting the presence of aquatic species, the factors affecting eDNA detection deserves substantial attention. Further, there is great variability between aquatic systems and study species. We used hellbender salamanders (Cryptobranchus alleganiensis) and occupancy modeling to investigated the factors affecting the probability of occupancy and detection for eDNA survey and traditional survey methods. We collected eDNA via water samples, conducted exhaustive traditional hellbender surveys (i.e. snorkeling, rock-turning), and characterized instream habitat three times at each of the 25 sites. Both survey methods yielded similar detection estimates, but eDNA surveys detected hellbenders at 20% more sites. Hellbenders were more likely to occur at sites with increased substrate sizes and larger catchments. Detection estimates for traditional surveys were highest at sites with larger individuals and populations. Environmental DNA detection estimates were most affected by eDNA concentrations on the filter and the amount of sand at a site. This project expands upon the current knowledge of eDNA detection by demonstrating the importance of accounting for factors affecting the detection of eDNA such as substrate composition

ASSESSMENT OF HEAVY METALS CONTAMINATION FROM POINT SOURCES IN THE ABAROA - TUPIZA BASIN, BOLIVIAN SOUTHERN REGION

Heavy metal contamination in rivers downstream from mining operations is an important environmental concern due to the potential release of metals that affect water quality. The downstream transport of particulate bound metals and their subsequent storage in alluvial deposits is of particular concern because they may pose a significant threat to the quality of agricultural crops grown on floodplains. This study examines the downstream transport and storage of contaminated sediment derived from three mining centers in southern Bolivia: the Abaroa, the Chilcobija, and the Tatasi - Portugalete District. It also examines the consequences of erosion of mine tailings impounded within a small river valley at the Abaroa Mine site. Trace metal concentrations (including lead, zinc, and antimony) within the bed sediments of a bedrock constrained channel located immediately downstream of the Abaroa Mine gradually decrease downstream until reaching the Rio Chilco, where concentrations abruptly decrease. Metal concentrations within the bed sediments are similar to background concentrations within approximately 30 km of the Abaroa Mine.However, Pb and Zn concentrations locally increase farther downstream along the Rio Tupiza - San Juan del Oro as a result of the influx of mining debris from polymetallic mining operations within the Rio Tatasi basin and, to a lesser degree, the Rio Chilcobija. Downstream of the tributaries Rio Abaroa, and Rio Tatasi, Pb, Zn, and Sb concentrations decrease gradually until reaching concentrations similar to local background.The spatial distribution of metals in floodplain deposits differs from site to site. In floodplains closest to the mines such as FF-1 and FF-2, relatively elevated metal concentrations were found at sites located near the channel separated 10 and 35 m,whereas lower concentrations occurred at distances greater than 50 m from the channel. The opposite trend was observed in floodplain FF-3, and in the floodplain farthest downstream the difference in metal content was negligible. However, it is difficult to define a particular trend due to the small variations among and within the sites.Vertically, most of the floodplains exhibit the highest concentrations at the surface. Highly variable concentrations exist at greater depths, although the lowest metal concentrations were often at the base of the core. This spatial pattern suggests that sediments contaminated by Pb, Zn, and Sb have been deposited on the floodplain over the past several decades. Concentrations of heavy metals in floodplain deposits are higher than in channel bed sediments. Grain size data demonstrate that silt and clay is more abundant in floodplain deposits (~50%) than in channel sediments (~15%). These differences imply that differences in heavy metal concentrations are due to variations in the abundance of chemically reactive, fine sediments within the deposits. Locally, soil concentrations in floodplain soils exceed Dutch, Canadian, and German guideline values for agricultural use. In fact, the German guidelines are locally exceeded by two orders of magnitude. These data indicate that additional studies related to the accumulation of heavy metals within agricultural products should be conducted to more fully assess the potential impacts of metal contamination on human health.Impacts on human health and the environment caused by the Abar6a dam failure were apparently limited, as indicated by rapid downstream reduction in metal concentrations. The continuous inputs of sediments stored within the floodplain deposits during bank erosion may be a more important source of metals for the rivers

Predicting community college student success by participation in a first-year experience course

A first-year experience is a collaborative effort of many initiatives, with varying names that have the greatest impact on student success during the first year of college. A first-year experience course, a feature of the first-year experience, is an intervention program designed to increase student academic performance and integration (Braxton & McClendon, 2002; Karp, 2011; Pascarella & Terenzini, 2005; Reason, Terenzini, & Domingo, 2006; O’Gara, Karp, & Hughes, 2009; Tinto, 1975; Tinto & Pusser, 2006). An examination of a current intervention program, a first-year experience course, will provide community colleges with evidence a first-year experience course has on student and institutional success, as measured by academic performance, retention and graduation rates. This study will extend the current body of knowledge on the first-year experience, by examining the relationship between enrolling in a first-year experience course during the first year of college and student success

A descriptive study of exceptional children teacher practices in select North Carolina middle schools making adequate yearly progress

Rural, middle schools in North Carolina have struggled with the Students with Disabilities subgroup in making Adequate Yearly Progress (AYP) in reading since No Child Left Behind (NCLB) was passed. Consequences could be dire for a school and principal with a subgroup of these children who were unable to show growth each year toward total proficiency in reading by 2014. School children have been given the choice to attend other schools in the district and as a result whole school staff could replaced. This study sought solutions in a reading program and strategies that could help the students with specific learning disabilities (SLD) become proficient at grade level reading. A survey instrument was given to Exceptional Children’s (EC) directors, principals, and EC teachers and a focus group discussion was conducted with EC teachers in seven rural school systems in North Carolina who had been successful with making AYP for five years, 2005-2009. Results indicated that one particular reading program or strategy did make a difference, Direct Instruction. Data from the focus group discussion further indicated that these schools were using multiple reading programs and strategies plus quality staff development, whole school reform, creative scheduling, and a supportive principal to make the difference with the children identified as SLD, in the Students with Disabilities subgroup, as they strove for proficiency

An investigation of auditory laterality effects for verbal and melodic stimuli among musicians and nonmusicians

The purpose of this study was to determine if laterality effects differ for musicians and nonmusicians in the cerebral processing of musical stimuli. It was hypothesized that musicians, due to a more analytical approach to music listening, would demonstrate a right ear (left hemisphere) superiority for melodic stimuli, while nonmusicians would show a left ear (right hemisphere) dominance. Both groups, it was hypothesized, would reveal a right ear superiority for verbal stimuli. Verbal and melodic dichotic listening tasks were administered to a total of 44 musicians and 44 nonmusicians in two separate experiments. Group comparisons were made of right and left ear performance on each of the two auditory tasks. Both groups demonstrated a significant left ear effect for melodic recognition, which failed to support the first research hypothesis. The two groups demonstrated a nonmusicians right ear trend for verbal recall, which resulted in a lack of support for the second research hypothesis. It was concluded that the results of this study provide no evidence for laterality differences between musicians and nonmusicians in the processing of musical stimuli