Dynamic measurements and simulations of airborne picolitre-droplet coalescence in holographic optical tweezers

We report studies of the coalescence of pairs of picolitre aerosol droplets manipulated with holographic optical tweezers, probing the shape relaxation dynamics following coalescence by simultaneously monitoring the intensity of elastic backscattered light (EBL) from the trapping laser beam (time resolution on the order of 100 ns) while recording high frame rate camera images (time resolution <10 µs). The goals of this work are to: resolve the dynamics of droplet coalescence in holographic optical traps; assign the origin of key features in the time-dependent EBL intensity; and validate the use of the EBL alone to precisely determine droplet surface tension and viscosity. For low viscosity droplets, two sequential processes are evident: binary coalescence first results from overlap of the optical traps on the timescale of microseconds followed by recapture of the composite droplet in an optical trap on the timescale of milliseconds. As droplet viscosity increases, the relaxation in droplet shape eventually occurs on the same timescale as recapture, resulting in a convoluted evolution of the EBL intensity that inhibits quantitative determination of the relaxation timescale. Droplet coalescence was simulated using a computational framework to validate both experimental approaches. The results indicate that time-dependent monitoring of droplet shape from the EBL potential of high frame rate imaging to examine the coalescence of dissimilar viscosity droplets is discussed

Quality Evaluation of Data Management Plans at a Research University

With the emergence of the National Science Foundation (NSF) requirement for data management plans (DMPs), academic librarians have increasingly aided researchers in developing DMPs and disseminating research data. To determine the overall quality of DMPs at Wayne State University, the Library System’s Research Data Services (RDS) team evaluated the content of 119 DMPs from NSF grant proposals submitted between 2012 and 2014. The results of our content analysis indicate that, while most researchers understand the need to share data, many DMPs fail to adequately describe the data generated by the project, how data will be managed during the project, or how data will be preserved and shared after the completion of the project. Our results also show that DMP deficiencies vary across academic units, suggesting the need for differentiated outreach services to improve the strength of DMPs in future NSF grant proposals

Applications of advanced diffractive optical elements

Digital Optics Corporation is a UNC-Charlotte spin-off company, established to transfer technology developed at UNC-Charlotte for the design and manufacture Computer Generated Holograms (CGH's) and to market products based on CGH technology. DOC acquired core technologies from UNC-Charlotte including: (1) a CGH encoding process that can provide holograms with extremely high diffraction efficiency; (2) a low cost, high precision CGH manufacturing process; and (3) extensive holographic and refractive element design capabilities for design and evaluation of complex optical systems. These technologies have been used to design and/or manufacture optical components for a variety of applications including: (1) generation of Spot arrays; (2) fiber optic coupling elements; (3) optical interconnects between VLSI chips within and between multichip modules; and (4) imaging systems for head-mounted displays (HMD's)

Productivity estimation in Halodule wrightii: comparison of leaf-clipping and leaf-marking techniques, and the importance of clip height

We compared estimates of Halodule wrightii leaf growth rates obtained from leaf-clipping and leaf-piercing methods in a south Texas lagoon. Leaf clipping underestimated leaf production from 15 to 37% in winter and 25 to 60% in summer relative to leaf piercing. The underestimation of leaf-clipping derived growth rates were corrected using a linear regression between leaf growth rates determined by leaf-clipping and leaf-piercing methods. To examine the effect of clip height on H. wrightii leaf growth rate estimation, leaves were clipped at 0, 2, 4, 6, and 8 cm above the sediment. Leaves clipped at 2 cm exhibited the fastest leaf growth rate (average = 3.66 mm d–1) while leaves clipped at 8 cm had the slowest rate (average = 2.30 mm d–1). Depressed leaf growth rates for 8 cm clip height were likely due to the slowing of growth rate with increasing leaf age. Reduced growth rate for the 0 cm clip height treatment may be attributable to removal of nearly all photosynthetic tissue and limited below-ground resources. In design of leaf-clipping studies, it is suggested that the selection of clip height and the period of growth after clipping be optimized for each season of a study

Bullying, Safe Schools and Public Health: An Overview in Connecticut Private Schools

Introduction: As evident in the literature, bullying is frequently reported as a public health issue which affects the health and well-being of its victims. Bullying can also negatively impact student academic performance, leading to failure in school as evidenced by high and unacceptable drop-out rates and withdrawals.Objective: This research aimed to examine the issue of bullying from a public health point of view and to assess the issue in a specific region of Connecticut’s private school network. Furthermore, the study will assess the role of a Safe School Climate Coordinator in developing and implementing programs in schoolsthat can serve as effective policy measures to improve school safety with the goal of reducing or eliminating bullying activities in the school environment.Methods: The research employed the qualitative methodology from which six key themes emerged: mental health support; resource constraints; impact and influence of technology and social media; clear definition and distinction of bullying, harassment, and teasing; parental involvement and support; and importance and significance of the network’s culture. Nine participants from seven private schools in Connecticut took part in semi-structured interviews that were specially designed and conducted by the researchers. The nature of the interviews allowed participants to provide useful insights into the role they played in enhancing school climate by carefully developing and implementing policies and programs that reject violence and promote a school environment that is safe and conducive to learning.Findings: All participants expressed concerns over to the limited mental health services and support that is available within the private school system. All cited the possibility that students are under extreme pressure, and that students are often negatively affected by their home and living environments. These exposures can increase the urge to “act out” while they are in school. Due to the network’s strict policy on bullying and any related behavior, there is ongoing monitoring to ensure there is adherence to the requirements. One administrator noted that the individual who was responsible for the Newtown incident had mental health issues.Another administrator opined that recently more referrals have been made to the Department of Children and Families than ever before. There are genuine concerns about what is going on and home environment. When students come into the school environment, they should have a positive outlook and willingness to learn. The message that is conveyed through the interviews is that there is great worry about the future of some students. Mental health support would be helpful in elevating some of the problems that they see in the school environment and work hard to prevent.Conclusion: Where bullying is concerned, the public health toll is great and can have physical and emotional effects throughout the life of those who participate or are targeted. All efforts made to mitigate these deleterious effects in the early years of child and adolescence development is paramount in supporting the psychological well-being of the students

Hydrologic Variability and the Application of Index of Biotic Integrity Metrics to Wetlands: A Great Lakes Evaluation

Interest by land-management and regulatory agencies in using biological indicators to detect wetland degradation, coupled with ongoing use of this approach to assess water quality in streams, led to the desire to develop and evaluate an Index of Biotic Integrity (IBI) for wetlands that could be used to categorize the level of degradation. We undertook this challenge with data from coastal wetlands of the Great Lakes, which have been degraded by a variety of human disturbances. We studied six barrier beach wetlands in western Lake Superior, six drowned-river-mouth wetlands along the eastern shore of Lake Michigan, and six open shoreline wetlands in Saginaw Bay of Lake Huron. Plant, fish, and invertebrate communities were sampled in each wetland. The resulting data were assessed in various forms against gradients of human disturbance to identify potential metrics that could be used in IBI development. Our results suggested that the metrics proposed as potential components of an IBI for barrier beach wetlands of Lake Superior held promise. The metrics for Lake Michigan drowned-river-mouth wetlands were inconsistent in identifying gradients of disturbance; those for Lake Huron open embayment wetlands were yet more inconsistent. Despite the potential displayed by the Lake Superior results within the year sampled, we concluded that an IBI for use in Great Lakes wetlands would not be valid unless separate scoring ranges were derived for each of several sequences of water-level histories. Variability in lake levels from year to year can produce variability in data and affect the reproducibility of data collected, primarily due to extreme changes in plant communities and the faunal habitat they provide. Substantially different results could be obtained in the same wetland in different years as a result of the response to lake-level change, with no change in the level of human disturbance. Additional problems included limited numbers of comparable sites, potential lack of undisturbed reference sites, and variable effects of different disturbance types. We also evaluated our conclusions with respect to hydrologic variability and other major natural disturbances affecting wetlands in other regions. We concluded that after segregation of wetland types by geographic, geomorphic, and hydrologic features, a functional IBI may be possible for wetlands with relatively stable hydrology. However, an IBI for wetlands with unpredictable yet recurring influences of climate-induced, long-term high water periods, droughts, or drought-related fires or weather-related catastrophic floods or high winds (hurricanes) would also require differing scales of measurement for years that differ in the length of time since the last major natural disturbance. A site-specific, detailed ecological analysis of biological indicators may indeed be of value in determining the quality or status of wetlands, but we recommend that IBI scores not be used unless the scoring ranges are calibrated for the specific hydrologic history pre-dating any sampling year

A Dual TLR Agonist Adjuvant Enhances the Immunogenicity and Protective Efficacy of the Tuberculosis Vaccine Antigen ID93

With over eight million cases of tuberculosis each year there is a pressing need for the development of new vaccines against Mycobacterium tuberculosis. Subunit vaccines consisting of recombinant proteins are an attractive vaccine approach due to their inherent safety compared to attenuated live vaccines and the uniformity of manufacture. Addition of properly formulated TLR agonist-containing adjuvants to recombinant protein vaccines enhances the antigen-specific CD4+ T cell response characterized by IFN-γ and TNF, both of which are critical for the control of TB. We have developed a clinical stage vaccine candidate consisting of a recombinant fusion protein ID93 adjuvanted with the TLR4 agonist GLA-SE. Here we examine whether ID93+GLA-SE can be improved by the addition of a second TLR agonist. Addition of CpG containing DNA to ID93+GLA-SE enhanced the magnitude of the multi-functional TH1 response against ID93 characterized by co-production of IFN-γ, TNF, and IL-2. Addition of CpG also improved the protective efficacy of ID93+GLA-SE. Finally we demonstrate that this adjuvant synergy between GLA and CpG is independent of TRIF signaling, whereas TRIF is necessary for the adjuvant activity of GLA-SE in the absence of CpG

Automated prediction of mastitis infection patterns in dairy herds using machine learning

© 2020, The Author(s). Mastitis in dairy cattle is extremely costly both in economic and welfare terms and is one of the most significant drivers of antimicrobial usage in dairy cattle. A critical step in the prevention of mastitis is the diagnosis of the predominant route of transmission of pathogens into either contagious (CONT) or environmental (ENV), with environmental being further subdivided as transmission during either the nonlactating “dry” period (EDP) or lactating period (EL). Using data from 1000 farms, random forest algorithms were able to replicate the complex herd level diagnoses made by specialist veterinary clinicians with a high degree of accuracy. An accuracy of 98%, positive predictive value (PPV) of 86% and negative predictive value (NPV) of 99% was achieved for the diagnosis of CONT vs ENV (with CONT as a “positive” diagnosis), and an accuracy of 78%, PPV of 76% and NPV of 81% for the diagnosis of EDP vs EL (with EDP as a “positive” diagnosis). An accurate, automated mastitis diagnosis tool has great potential to aid non-specialist veterinary clinicians to make a rapid herd level diagnosis and promptly implement appropriate control measures for an extremely damaging disease in terms of animal health, productivity, welfare and antimicrobial use

Dairy herd mastitis and reproduction: using simulation to aid interpretation of results from discrete time survival analysis

Probabilistic sensitivity analysis (PSA) is a simulation-based technique for evaluating the relative importance of different inputs to a complex process model. It is commonly employed in decision analysis and for evaluation of the potential impact of uncertainty in research findings on clinical practice, but has a wide variety of other possible applications. In this example, it was used to evaluate the association between herd-level udder health and reproductive performance in dairy herds. Although several recent studies have found relatively large associations between mastitis and fertility at the level of individual inseminations or lactations, the current study demonstrated that herd-level intramammary infection status is highly unlikely to have a clinically significant impact on the overall reproductive performance of a dairy herd under typical conditions. For example, a large increase in incidence rate of clinical mastitis (from 92 to 131 cases per 100 cows per year) would be expected to increase a herd's modified FERTEX score (a cost-based measure of overall reproductive performance) by just £4.501 per cow per year. The herd's background level of submission rate (proportion of eligible cows served every 21 days) and pregnancy risk (proportion of inseminations leading to a pregnancy) correlated strongly with overall reproductive performance and explained a large proportion of the between-herd variation in performance. PSA proved to be a highly useful technique to aid understanding of results from a complex statistical model, and has great potential for a wide variety of applications within the field of veterinary science