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Loess soils of the Midsouth USA are easily eroded, contain little organic matter, and are drought susceptible. Conservation tillage and cover crops may increase cotton (Gossypium hirsutum L.) yields on these soils. A field study was conducted from 1995 through 2001 on Gigger silt loam (fine‐silty, mixed, thermic Typic Fragiudalfs) to study effects of tillage, cover crops, and N rates on yield and fiber properties. Cotton was grown without tillage (no‐till) and with surface tillage (surface till) following annual winter cover crops of wheat (Triticum aestivum L.), hairy vetch (Vicia villosa Roth), or volunteer winter vegetation (native) and with fertilizer N rates of 0, 39, 78, 118, or 159 kg ha−1. Tillage, cover crop, and N rate affected cotton yield. The till × N rate, till × cover crop, and cover crop × N rate interactions were significant. Yields of cotton receiving zero fertilizer N were 28 to 49% higher under surface till than under no‐till. In contrast, cotton receiving optimum N produced 5 to 11% higher yields with no‐till than with surface till. Following native cover, 118 kg N ha−1 optimized cotton lint yields under no‐till (1249 kg ha−1) whereas only 78 kg N ha−1 was necessary to optimize yields under surface till (1117 kg ha−1). Following wheat, 118 kg N ha−1 optimized lint yields under both no‐till (1246 kg ha−1) and surface till (1185 kg ha−1). Following hairy vetch, no fertilizer N was needed to optimize yields under no‐till (1238 kg ha−1) and surface till (1160 kg ha−1). Tillage, cover crop, and N rate did not appreciably compromise or improve fiber quality. After 7 yr, lint yields did not decrease in systems employing no‐till and cover crops, and combined with optimal fertilizer N, these conservation practices increased cotton yields.

Cellular therapy is emerging as a promising alternative to conventional immunosuppression in the fields of hematopoietic stem cell (HSC) transplantation, autoimmune disease, and solid organ transplantation. Determining the persistence of cell-based therapies in vivo is crucial to understanding their regulatory function and requires the combination of an extremely sensitive detection technique and a stable, long-lifetime cell labeling agent. This paper reports the first application of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to perform single cell detection of T cell populations relevant to cellular immunotherapy. Purified human CD4 + T cells were labeled with commercially available Gd-based magnetic resonance imaging (MRI) contrast agents, Omniscan and Dotarem, which enabled passive loading of up to 10 8 Gd atoms per cell. In mixed preparations of labeled and unlabeled cells, LA-ICP-MS was capable of enumerating labeled cells at close to the predicted ratio. More importantly, LA-ICP-MS single cell analysis demonstrated that the cells retained a sufficient label to remain detectable for up to 10 days post-labeling both in vitro and in vivo in an immunodeficient mouse model.

We describe a reproducible, simple and rapid procedure for the assessment of nickel levels in occupationally exposed individuals.

The structure of nine commercially manufactured aluminum-containing adjuvants was investigated by X-ray diffraction, infrared spectroscopy, transmission electron micrography, and energy dispersive spectrometry. Seven samples which were labeled as aluminum hydroxide were identified as boehmite, a crystalline aluminum oxyhydroxide [AlO(OH)]. However, the degree of crystallinity varied between the samples. Two samples which were labeled as aluminum phosphate were found to be amorphous aluminum hydroxyphosphate. Buffer anions and sulfate anions substitute for hydroxyls in the amorphous aluminum hydroxide formed by the in situ alum precipitation method. Finally, the aluminum-containing adjuvant in diphtheria and tetanus toxoid, U.S.P., produced by three manufacturers was characterized.

Administering immunoregulatory cells to patients as medicinal agents is a potentially revolutionary approach to the treatment of immunologically mediated diseases. Presently, there are no satisfactory, clinically applicable methods of tracking human cells in patients with adequate spatial resolution and target cell specificity over a sufficient period of time. Laser ablation–inductively coupled plasma mass spectrometry (LA-ICP-MS) represents a potential solution to the problem of detecting very rare cells in tissues. In this article, this exquisitely sensitive technique is applied to the tracking of gold-labeled human regulatory macrophages (Mregs) in immunodeficient mice. Optimal conditions for labeling Mregs with 50-nm gold particles were investigated by exposing Mregs in culture to variable concentrations of label: Mregs incubated with 3.5 × 109 particles/ml for 1 h incorporated an average of 3.39 × 108 Au atoms/cell without loss of cell viability. Analysis of single, gold-labeled Mregs by LA-ICP-MS registered an average of 1.9 × 105 counts/cell. Under these conditions, 100% labeling efficiency was achieved, and label was retained by Mregs for ≥36 h. Gold-labeled Mregs adhered to glass surfaces; after 24 h of culture, it was possible to colabel these cells with human-specific 154Sm-tagged anti–HLA-DR or 174Yb-tagged anti-CD45 mAbs. Following injection into immunodeficient mice, signals from gold-labeled human Mregs could be detected in mouse lung, liver, and spleen for at least 7 d by solution-based inductively coupled plasma mass spectrometry and LA-ICP-MS. These promising results indicate that LA-ICP-MS tissue imaging has great potential as an analytical technique in immunology.

Cotton (Gossypium hirsutum L.) yield is influenced by tillage, cover crop, and N fertility, but the plant growth and yield component responses related to these yield responses have not been well defined. A field study was conducted from 1991 through 2001 on Gigger silt loam (fine‐silty, mixed, thermic Typic Fragidaulf) to determine the long‐term effects of tillage practices, cover crops, and N fertilization rates on cotton growth and yield components. Cotton was grown continuously without tillage (no‐till) or with surface tillage (surface till) following annual winter cover crops of wheat (Triticum aestivum L.), hairy vetch (Vicia villosa Roth), and volunteer winter vegetation in plots receiving fertilizer N rates of 0, 39, 78, 118, or 159 kg ha−1. Tillage practice, cover crop, and N rate significantly affected cotton plant height, main‐stem node number, number of nodes above white flower (NAWF), main‐stem internode length, lint fraction, percentage first harvest, individual boll weight, and boll number per square meter. Increases in lint yields were associated with increases in plant height (r = 0.73 to 0.95), node number (r = 0.71 to 0.83), internode length (r = 0.44 to 0.91), NAWF (r = 0.65 to 0.90), boll weight (r = 0.12 to 0.86), and boll number per square meter (r = 0.91 to 0.93). Lint fraction showed no association or, in some years, a negative association with lint yield (r = −0.12 to −0.70). No‐till management and optimal N rate improved the environment for plant growth, which enhanced several growth parameters and yield components that were associated with increases in yield.