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A relatively large number of studies have investigated the effectiveness of vegetated buffer strips at reducing the movement of pesticides and nutrients from agriculture fields. This review outlines the observed influence of different factors (e.g., buffer width, slope, runoff intensity, soil composition, plant community) that can influence the efficacy of vegetated buffers in pesticide and nutrient retention. The reported effectiveness of vegetated buffers reducing the movement of pesticides and nutrients ranged from 10 to 100% and 12-100%, respectively. Buffer width is the factor that is most frequently considered by various jurisdictions when making recommendations on vegetated buffer strip implementation. However, the literature clearly illustrates that there is a great deal of variation in pesticide or nutrient reduction for a given buffer width. This indicates that other factors play an important role in buffer efficacy (e.g., ratio of source area to buffer area, soil composition and structure, runoff intensity, plant community structure) in addition to the width of the vegetative buffer area. These factors need to be considered when making recommendations on vegetated buffer strip construction in agroecosystems. This review has also identified a number of other gaps in the understanding of the effectiveness of vegetated buffers at reducing the movement of pesticides and nutrients from the areas of application., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

A vegetated buffer, barrier, or filter strip is a parcel of land that is designated to separate land used for agriculture from valued aquatic or terrestrial habitats. It exists partly with the intent to diffuse runoff and to impeded sediment, nutrients, pesticides, and other constituents from reaching off-site surface waters. Mandatory buffer implementation is regulated at various levels of government in North America - from the federal to the state and provincial levels, and by some municipalities and counties. To better understand the degree and breadth of oversight, we undertook a comprehensive search and review of vegetative buffer regulations across North America. We determined the width of buffer required, under what habitat or field conditions, for which pesticides, and application type, amongst other attributes. For ground application, margins ranged from 1 m to upwards of greater than 4000 m depending on protection goals, with some being compound specific and others being generally applied to all registered pesticides/compounds. These buffers tended to be used most often to protect surface water, groundwater (e.g. drinking water wells), and nearby sensitive crops, but the required distances are generally not consistent between jurisdictions, regardless of the stated protection goals. We recommend that a thorough science-based review take place, with input from relevant stakeholders, to harmonize vegetated buffer size for effective surface water protection where ecological, climatic, and agricultural conditions are sufficiently similar in North America., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

There is speculation that high cytotoxic T lymphocyte precursor frequencies (CTLpf) correlate with poor clinical outcome of bone marrow/organ transplantation. It is also believed that human umbilical cord blood is immunologically naive, and, therefore cord blood T cells may be less able to mediate graft versus host disease than marrow-derived T cells. CTLpf were determined in peripheral blood mononuclear cells collected from healthy adults, human umbilical cord blood and renal dialysis patients who were randomly selected and entered into this study. A highly sensitive non-radioactive Europium release cytotoxicity assay was optimized and modified to carry out the CTLpf estimation by using the principle of limiting dilution analysis. The results of CTLpf in healthy adults ranged from 1/694 to 1/66,666, median 1/7,339 (n=10); cord blood ranged from 1/1,562 to 1/35,714, median 1/10,162 (n=6) and dialysis patients ranged from 1/1,054 to 1/17,857 median 1/5,208 (n=9). The results demonstrated that there is little difference of CTLpf median values between the groups, but there is a wide variation of CTLpf between individuals within a population. It suggests that this variation should be taken into account when considering CTLpf assay as pre-transplantation cross-match procedure.

We describe the design and operation of a high speed optical tomography system for measuring two-dimensional images of a dynamic phase object at a rate of 5 kHz. Data from a set of eight Hartmann wavefront sensors is back-projected to produce phase images showing the details of the inner structure of a heated air flow. The tomographic reconstructions have a spatial resolution of approximately 2.0 mm and can measure temperature variations across the flow with an accuracy of about 0.7 C. Series of animated reconstructions at different downstream locations illustrate the development of flow structure and the effect of acoustic flow forcing.