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Downstream of the Earth's bow shock, the magnetosheath can exhibit strong turbulence. This turbulent cascade is associated with electron‐scale current sheets where magnetic reconnection can occur. We present data from NASA's Magnetospheric Multiscale mission during a turbulent magnetosheath interval that includes two electron‐scale reconnecting current sheets, one with higher guide field and one that is closer to antiparallel. We examine the characteristics of energy conversion and the role of parallel electric fields and waves in that energy conversion. The high‐guide field reconnection event shows energy conversion dominated by electric fields and currents parallel to the background magnetic field, while the lower guide field event is perpendicular dominated, consistent with observations of laminar reconnecting current sheets in the magnetosheath. Both current sheets exhibit signs of a parallel electric field acceleration channel, and the higher guide field event shows whistler‐mode waves at the x‐line. Both current sheets show variation in dissipation along the n‐direction, with perpendicular dissipation on one side and parallel on the other. Between the two is a dispersion of pitch angles from 90° to 0° or 180°. This dispersion is likely caused by the acceleration channel and rapidly suppresses whistler waves, suggesting whistler waves do not contribute to the dissipation in guide field reconnection. Key Points: Two magnetic reconnection events are observed in the turbulent magnetosheath with different guide fieldBoth current sheets exhibit a parallel electric field acceleration channel that changes the anisotropy of the electronsThis acceleration channel is sufficient to suppress whistler waves near the diffusion region [ABSTRACT FROM AUTHOR]

All living organisms need essential nutrient elements to survive and thrive. For plants, of the 14 essential nutrient elements, over half show deficiency symptoms that include chlorosis. However, this is for plants with green leaves. For purple leaf basil, there has been no reported research on how microelement deficiency is expressed, diagnosed and/or corrected. The purpose of this research was to visually and quantitatively identify micronutrient element deficiencies, specifically, iron (Fe), manganese (Mn) and zinc (Zn), in 'Red Rubin', a purple leaf basil. To do this, three cultivars of basil, Italian Large Leaf, a green leaf basil; Aromatto, a mottled purple and green leaf basil; and Red Rubin, a purple leaf basil, were grown for 13–16 weeks. The experiment design was a split-plot with four treatments and the three cultivars. Data included visual observations, relative greenness (SPAD) measurements and tissue nutrient analysis. 'Red Rubin' leaves had similar SPAD values to both of the other cultivars. When Fe, Mn or Zn was deficient, purple pigment was lost. However, visual deficiencies such as yellowing and an increase in green color either veinally, interveinally or on the leaf margins varied. Based upon overlapping symptoms and based on tissue analysis, it is possible that there exists a 3-way or even 4-way interaction/balance among the minor elements Fe, Mn, Zn and possibly copper (Cu). [ABSTRACT FROM AUTHOR]

The sustainable production of upland cotton, an economically important fiber crop, is threatened by changing environmental factors including high temperatures and low-soil water content. Both high heat and low-soil water can reduce net photosynthesis resulting in low fiber yields or poor fiber quality. Leaf chlorophyll content has a direct relationship with photosynthetic rate. Understanding how high heat and low-soil water affect chlorophyll content can identify opportunities for breeding improvement that will lead to sustainable fiber yields. A two-year field trial located in Maricopa Arizona measured leaf chlorophyll content, available soil water, ambient air temperatures, and cotton growth measurements collected by a high-clearance tractor equipped with proximal sensors. The results showed that low-soil water significantly increased leaf chlorophyll content, while high temperatures significantly reduced content. Structured equation modeling revealed that cotton may divert available resources to leaf area and chlorophyll content for the production of photosynthates during periods of high temperatures. [ABSTRACT FROM AUTHOR]

pH variations and peak activity results at about pH 8.5 regulate the rate of autophosphorylation of CheA in Escherichia coli. The ternary complexes, formed by transducers Tar and Tsr with CheA and CheW, stimulate the autokinase activity of CheA and pH enhances the formation of these complexes. pH influences the coupling of Tsr and Tar to CheA in different ways.

Strawberries are only seasonally available in Nebraska (NE). If an affordable heated structure can be designed, then opportunity exists to increase on-farm income by producing strawberries off-season during high-value market periods. A series of university greenhouse trials were conducted from 2010 to 2012. The varieties Evie-2 and Seascape were identified as being most productive under a low technology growing scheme. A new research project, which ran from fall to late spring (2013–2014), was designed to determine if this production scheme would translate to a commercial grower. Varieties Seascape and Evie-2 (each at two grades indicated by +) and San Andreas plants were grown simultaneously at the university research greenhouse and a cooperative specialty crop grower greenhouse, similar structures and production timelines. Top performers for both experiment locations were 'Evie-2ʹ, and 'Evie-2+' plants, with average harvest berry weights (marketable) per plant (pp) of over 0.454 kg, and 'Seascape' with 0.390 kg. 'Seascape+' plants performed well at the cooperator location (0.399 kg pp), but not at the university location. 'San Andreas' plants performed well at the university location with 0.454 kg pp but not at the cooperator location. Productivity was greatest during the winter-spring season, which accounted for more than 82% of the total berry mass harvested at the cooperator site and 88% at the university site. The results support the concept that the growing system used within a controlled university research setting is representative of the crop productivity a specialty crop grower might expect, particularly when strawberries are grown in late winter and early spring. However, securing low fuel costs, eliminating delivery and having a secondary market for culls is key for profitability. [ABSTRACT FROM AUTHOR]

Use of active optical sensors (AOS) in nitrogen (N) management of row crops continues to grow. Since the first studies in the mid‐1990s, several commercial AOS are now available. Typically, canopy reflectance in red and near infrared (NIR) bands are used to calculate the normalized difference vegetation index (NDVI). More recently, commercially available AOS include a third, red‐edge band that allows the calculation of additional vegetation indices (VIs). We present two studies of five site‐years of N management studies in Maricopa, AZ, on a Casa Grande sandy loam with cotton (Gossypium hirsutum L.). The 2014–2015 study was conducted under an overhead sprinkler irrigation system (OSI), and the 2016–2018 study was in subsurface drip irrigation (SDI). The study objective was to compare the ability of 12 different VIs to detect N deficiency among N treatments from shortly after emergence to mid‐bloom. In the OSI study, which showed delayed, small N treatment effects, NDRE and the chlorophyll index using amber (CIRE) detected N deficiency in zero‐N and in reduced N‐reflectance‐based plots 7–23 d before other VIs did. With SDI, the choice of VI was less critical as several VIs could distinguish N deficiency in zero‐N and in reflectance plots. The commonly used NDVI red (NDVIR) only detected N deficiency in reflectance plots in one of five site‐years. In conclusion, we recommend the use of AOS with NIR and red‐edge bands and the calculation of NDRE or CIRE to guide AOS‐based in‐season N management of irrigated cotton. [ABSTRACT FROM AUTHOR]

Cryo-electron microscopy and single-particle image analysis are frequently used methods for macromolecular structure determination. Conventional single-particle analysis, however, usually takes advantage of inherent sample symmetries which assist in the calculation of the structure of interest (such as viruses). Many viruses assemble an icosahedral capsid and often icosahedral symmetry is applied during structure determination. Symmetry imposition, however, results in the loss of asymmetric features of the virus. Here, we provide a brief overview of the methods used to investigate non-symmetric capsid features. These include the recently developed focussed classification as well as more conventional methods which simply do not impose any symmetry. Asymmetric single-particle image analysis can reveal novel aspects of virus structure. For example, the VP4 capsid spike of rotavirus is only present at partial occupancy, the bacteriophage MS2 capsid contains a single copy of a maturation protein and some viruses also encode portals or portal-like assemblies for the packaging and/or release of their genome upon infection. Advances in single-particle image reconstruction methods now permit novel discoveries from previous single-particle data sets which are expanding our understanding of fundamental aspects of virus biology such as viral entry and egress. [ABSTRACT FROM AUTHOR]

Nitrogen fertilizer use efficiency (NUE) is low in surface-irrigated cotton (Gossypium hirsutum L.), especially when adding N to irrigation water. A NO3 soil-test algorithm was compared with canopy reflectance-based N management with surface-overhead sprinkler-irrigation in central Arizona. The surface irrigation studies also compared fertigation of N fertilizer with knifing-in of N and the addition of a urease and nitrification inhibitor (Agrotain Plus, Koch Agronomic Services, Wichita, KS) to urea ammonium nitrate (UAN). Cotton lint and seed yields responded positively to N fertilizer in all four site-years. Recovery efficiency (RE) of N at low N fertilizer rates (60 to 76 kg N ha-1) ranged from 21 to 61% with surface irrigation and from 81 to 97% with overhead sprinkler irrigation. Deep percolation below 1.8 m was 4 to 11% of applied surface irrigations and rain, but was undetectable in the overhead sprinkler. Leaching of NO3 was apparently the largest N loss pathway in the surface-irrigated system. Fertigating UAN into surface irrigation resulted in similar lint yields and RE as knifing UAN. Use of Agrotain Plus with UAN gave similar yields and RE as using UAN alone. Reflectance-based N management using normalized difference vegetation index-amber (NDVIA) saved 50% of N fertilizer of the full soil-test based dose without a yield reduction in three of four site-years. Nitrogen fertilizer was over-prescribed with the soil-test-based treatment. This may have been due to not accounting for N mineralization, which the reflectance method indirectly measures. [ABSTRACT FROM AUTHOR]

Climate warming may raise wheat (Triticum aestivum L.) yields in cooler climates and lower them in warmer climates. To understand these contrasting effects, infrared heating lamps were used to warm irrigated spring wheat by 1.5° C (day) and 3.0° C (night) above unheated controls during different times of the year at Maricopa, AZ. Changes in wheat growth with warming were used to test hypotheses for temperature effects on crop growth in the process model ecosys. Infrared heating substantially raised phytomass growth and grain yield under lower air temperature (Ta) following plantings from September through December. The same heating, however, lowered growth and yield under higher Ta following plantings from January through March. Gains in wheat yield of as much as 200 g C m-2 with heating under lower Ta were attributed in the model to more rapid CO2 fixation and to reduced chilling effects on seed set. These gains were only partially offset by losses from shortened wheat growth periods. Losses in wheat yield of as much as 100 g C m-2 with heating under higher Ta were attributed in the model to adverse effects of heating on crop water status and on CO2 fixation vs. respiration, to greater heat stress effects on seed set, and to shortened crop growth periods. Model hypotheses thus explained contrasting effects of heating on wheat yields under different Ta found in the field experiment as well as in many earlier studies. Well-constrained tests of these hypotheses are vital for models used to project climate change impacts on agricultural ecosystems. [ABSTRACT FROM AUTHOR]

A patient with respiratory syncytial virus (RSV) infection and severe combined immunodeficiency was studied during a 3-month period of bone marrow transplantation and palivizumab infusion. No RSV isolates with palivizumab escape mutations were identified. Donor lymphocytes, including CD8 cells, appeared to markedly reduce the RSV load but increased the pulmonary symptoms. Immunosuppressive therapy ameliorated lung disease but allowed the RSV load to rebound. [ABSTRACT FROM AUTHOR]

Aerosol samples were collected and analyzed to characterize the spatial and temporal variations in the concentrations of plutonium and selected inorganic substances in the atmosphere around the Waste Isolation Pilot Plant (WIPP). High-volume aerosol sampling was conducted at three sites: (1) On Site, (2) Near Field, and (3) Cactus Flats. [sup 239,240]Pu was determined by alpha spectrometry following chemical separations; mass loadings were determined gravimetrically. A separate set of low-volume aerosol samples was analyzed for major ions using ion chromatography and for trace elements by inductively-coupled plasma emission spectrometry and mass spectrometry. The average [sup 239,240]Pu activity concentrations in total suspended particle (TSP) samples (12 to 16 nBq m[sup -3]) were consistent with those previously reported, but they varied strongly with season, with the highest values generally in spring. Further, the [sup 239,240]Pu activity concentrations were comparable among the three sites, and therefore there was no evidence for elevated [sup 239,240]Pu activities due to WIPP operations. The fraction of the [sup 239,240]Pu activity concentrations in the PM[sub 10] samples (particles less than 10 µm diameter) relative to TSP was lower than the corresponding PM[sub 10]/TSP ratios of either high-volume mass or several inorganics (sulfate, aluminum or lead), indicating that [sup 239,240]Pu tends to be on large particles. Aerosol mass loadings (µg m[sup -3]) and [sup 239,240]Pu activity concentrations were correlated for all sets of samples, but at On Site, the TSP samples showed higher mass to [sup 239,240]Pu ratios than the other sites. Thus activities or processes occurring at or near the WIPP site evidently produced aerosols that contributed to the mass loadings but contained less [sup 239,240]Pu than ambient aerosols. About 63% of the variability in [sup 239,240]Pu activity concentrations was explained by wind travel, sampling location, length... [ABSTRACT FROM AUTHOR]

Today the many varieties of poinsettia available for production-dates printpubdate="07/01/2002" are typically designated as one of two types: dark leaf vs. green leaf/light leaf types. Research has shown that dark leaf varieties require less fertilizer than green leaf types. The objectives of this research were to evaluate the effect of varying nitrogen (N) and sulfur (S) fertilizer applications on leaf anatomy, essential nutrient elements, and the growth and development of a dark leaf variety of poinsettia. Vegetative “Freedom Red” poinsettias were grown in a soilless mix following a typical production-dates printpubdate="07/01/2002" schedule except for fertilization. Plants received N at 50, 100, 200, or 275 mg L-1 in combination with S at 0, 12.5, or 25 mg L-1. Visual observations of plants indicated that “Freedom Red” poinsettia responded differently to various application rates of N and S. Plants inferior in size, form, and color were produced when S was applied at rates of 0 mg L-1 in combination with any level of N and 12.5 or 25 mg L-1 S at 50 or 100 mg L-1 N. Specific N-S ratios of applied nutrients were not a reliable predictor of visual quality. Anatomically, “Freedom Red” leaves were typical of poinsettia, consisting of a single-layer papillate epidermis and a single row of palisade cells. There appeared to be one notable difference among treatment extremes: in treatments receiving 50 mg L-1 N, the length of palisade cells was nonuniform from one cell to the next. Leaf tissue analysis indicated that most of the essential elements were present in sufficient amounts. Nitrogen and S concentrations ranged from below critical level to normal range in direct response to the quantity of each nutrient applied. The application of N affected boron, copper, and chlorine while S had an effect on molybdenum. [ABSTRACT FROM AUTHOR]

Although there is IgG subclass restriction in the antibody responses to most antigens, our data indicate that the human IgA subclasses, IgA, and IgA2, do not demonstrate a similar antigen specific restriction. We did not find evidence for IgA subclass restriction in the antibody responses to phosphorylcholine (PC), β lactoglobulin or tetanus toxoid. These antigens were chosen to represent carbohydrate-like versus protein antigens and antigens presented through the mucosal route versus the humoral route. For each of these antigens the proportion of antigen specific IgA that was IgA1 and IgA2 was similar to that of total serum IgA. IgA anti-PC, which is thought to be directed against the phosphorylcholine moieties found on certain bacterial polysaccharides, could be found in the serum of all individuals tested and constituted 0.062–0.088% of the total serum IgA. IgA anti-β lactoglobulin and anti-tetanus toxoid could be measured only in the serum of selected individuals, usually those with known milk protein sensitivity, or those recently immunized with letanus toxoid. The lack of a marked subclass restriction of IgA responses to these antigens stands in contrast to results obtained by others for IgG antibodies, in which carbohydrates and proteins preferentially stimulate antibodies in different IgG subclasses. [ABSTRACT FROM AUTHOR]

Studies the effects of pH in the autophosphorylation of the gene cheA in Escherichia coli. Modulation of the swimming behavior of Escherichia coli; Cytoplasmic signal transduction protein; Chemotactic effects of modifications.

When a flagellar filament of a bacterial cell such as Escherichia coli is fixed to a glass surface, the cell body spins alternately clockwise and counterclockwise at speeds of up to 15 Hz. In cells wild type for chemotaxis, reversals occur about once per second. A typical experiment on bacterial behavior involves data collected from as many as 30 such cells over periods of about an hour. A system is described that makes practical detailed analysis of such a large body of data. Microscopic fields, each containing many tethered cells, were recorded on VHS cassettes with a shuttered multiframe video camera. The tapes were played back through hardware that encoded information from successive images of a given cell and passed that information on to a minicomputer. This computer, following instructions provided in an editing session, identified intervals during which the cell was rotating clockwise, rotating counterclockwise, or remained stationary. Output files were generated listing the times at which transitions between these states occurred and the speeds of the cell averaged over successive time periods. This output was then combined with that from other cells and/or processed by various applications programs. [ABSTRACT FROM AUTHOR]

The ability of IVIG to increase platelet counts in patients with idiopathic thrombocytopenic purpura suggests its potential usefulness in other disease states characterized by low platelet counts. This possibility was evaluated in nine patients with the Wiskott-Aldrich syndrome (WAS) who received IVIG, at a dose of 400 mg/kg every 4 weeks. The mean platelet count prior to institution of IVIG was 32,00O/cumm (range 2,400 to 98,000). Following administration of IVIG. the platelet count ranged between 5,000 and 85,00O/cumm. There were no immediate increases in platelet counts after IVIG infusion in any patient who had serial platelet counts. During treatment. patients were not given any routine platelet transfusions for low platelet counts. However. while on IVIG, two patients showed a good response to platelet transfusion prior to surgical procedures. In conclusion, chronic IVIG therapy does not appear to affect platelet counts in patients with the Wiskott-Aldrich syndrome. [ABSTRACT FROM AUTHOR]

A systematic assessment of infections beginning early in pregnancy is necessary to determine the true role of infections in pregnancy loss, given that infections could readily arise only after fetal demise. To this end, we have prospectively determined the frequency of infections in pregnant women who were subjects in a multi-centre US study. Insulin-dependent diabetic subjects and controlled subjects were recruited either before conception (86%) or at the latest within 21 days of conception (14%). We collected data prospectively on all important risk factors and potential confounding variables, seeing 386 diabetic subjects weekly and 432 control subjects every other week during the first trimester. At each visit we inquired about untoward events and explicitly about fever or infections. We found no clinical evidence that infection occurred more often in the 116 subjects experiencing pregnancy loss as compared to the 702 having successful pregnancies. This held both for the 2 week interval in which a given loss was recognized clinically as well as in the prior 2 week interval. Similar findings were not only observed for both the control as well as diabetic subjects but also when data were stratified by genital infection only or by systemic infection only. Our prospective data suggest that the attributable risk of infection in first trimester spontaneous abortion is small. [ABSTRACT FROM AUTHOR]

The magnitude and the kinetics of the serum-specific polymeric (p-) and monomeric (m-) IgA antibody responses were analysed following parenteral stimulation with tetanus toxoid (TT) vaccine in 10 volunteers, 5-20 years after a previous boost. A rapid marked serum IgA antibody response involving both the monomeric and polymeric components of IgA was observed: m-IgA and p-IgA antibodies reached a peak of serum activity at about 11 days, around 6 days before the peak of IgG antibody activity. At the peak of the IgA response, p-IgA accounted for approximately half of the anti-TT activity (median 54%, 25-79%). However, p-IgA antibodies rapidly disappeared from serum over a few weeks, whereas the serum m-IgA antibody response was maintained over a prolonged period of time. For one subject out of five, anti-TT IgA were also detected in saliva with a peak of activity earlier than in serum. Calculation of the albumin relative coefficient of excretion for anti-TT IgA in this saliva suggested a local synthesis of these antibodies. The present study indicates that a polymeric IgA antibody response in serum can be produced by parenteral immunization in primed individuals, and it raises the question of the mechanisms that control polymeric versus monomeric IgA production. [ABSTRACT FROM AUTHOR]

Background: Previous studies linked metformin use to vitamin B12 deficiency and demonstrated that the prevalence of vitamin B12 monitoring remains low. Objective: This study aimed to assess the occurrence of monitoring vitamin B12 levels in a diverse population. Methods: This was a retrospective chart review of adult patients with type 2 diabetes on metformin doses ≥ 1000 mg for ≥ 6 months at five Federally Qualified Health Centers (FQHC) and one Program of All-Inclusive Care for the Elderly (PACE). Charts were reviewed for occurrence of monitoring vitamin B12 levels in the past 5 years. Data collected included patient demographics, laboratory data, other potential vitamin B12 level lowering agents, active prescription for vitamin B12 supplementation, concomitant diabetes medications and metformin total daily dose. Results: Of the 322 patients included, 25% had a vitamin B12 level measured in the previous five years. Among the patients with a vitamin B12 level, 87.7% were within the normal range (>350 pg/mL), 11.1% were low (200-300 pg/mL), and only one patient (1.2%) was deficient (