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Solid organ transplant recipients (SOTRs) are at increased risk of developing and dying from cancer. However, controversies exist around cancer screening in this population owing to reduced life expectancy and competing causes of death. This systematic review assesses the availability, quality and consistency of cancer screening recommendations in clinical practice guidelines (CPGs). We systematically searched bibliographic databases and gray literature to identify CPGs and assessed their quality using AGREE II. Recommendations were extracted along with their supporting evidence. Thirteen guidelines were included in the review. CPGs for kidney recipients were the most frequent source of screening recommendations, and recommendations for skin cancer screening were most frequently presented. Some screening recommendations differed from those for the general population, based on literature demonstrating higher cancer incidence among SOTRs versus direct evidence of screening effectiveness. Relevant stakeholders such as oncology specialists, primary care providers and public health experts were not involved in the formulation of the screening recommendations. In conclusion, although several guidelines make recommendations for cancer screening in SOTRs, the availability of cancer screening recommendations varied considerably by transplanted organ. More studies are required to inform cancer screening recommendations in SOTRs, and guideline development should involve transplant patients, oncologists and cancer screening specialists. This systematic review assesses cancer screening recommendations in posttransplant care clinical practice guidelines and finds that although 13 guidelines make recommendations for cancer screening in transplant recipients, the availability of recommendations varies considerably by transplanted organ and that relevant stakeholders were not involved in the formulation of screening recommendations. See Blosser's editorial on page 9.

Fusarium wilt disease of watermelon (Citrullus lanatus(Thunb.) Matsum & Nakai), caused by Fusarium oxysporumf. sp. niveum(FON), is one of the limiting factors of worldwide watermelon production. In this study, a Fusarium wilt resistant watermelon JSB, which was derived from a spontaneous mutation of the susceptible Sugar Baby (SB), was used to investigate histopathology. The number and diameter of xylem vessels in the root (10mm below the shoot base) of resistant JSB plants were significantly higher than those in susceptible SB plants. At 9 days post inoculation (dpi), using the plate assay on Nash-PCNB media, FON could be recovered from 86% of the roots in the symptomless plants of both watermelon lines, and from 55% and 64% of the stem segments (5mm above the shoot base) in resistant and susceptible plants, respectively. In paraffin and free-hand tissue sections, at 8, 13, and 35dpi, the xylem of roots and stems close to the soil surface in resistant watermelon JSB plants was also colonised by FON, but to a much lower percentage than the susceptible SB ones. No colonisation below the middle of stems was observed in the resistant JSB plants. The susceptible plants grown in infested soil were all dead by 35dpi, while the resistant plants remained healthy. These observations suggest that reducing FON colonisation in the vascular systems of the host may contribute to the resistance in JSB. Furthermore, the higher expression of the phenylalanine ammonia lyase (PAL) gene in JSB induced by FON and the effects of PAL inhibitor on the resistance of JSB suggested that PAL is involved in resistance of watermelon to Fusarium wilt pathogen.

Abstract: A new method for producing microlens array with large sag heights is proposed for integrated fluorescence microfluidic detection systems. Three steps in this production technique are included for concave microlens array formations to be integrated into microfluidic systems. First, using the photoresist SU-8 to produce hexagonal microchannel array is required. Second, UV curable glue is injected into the hexagonal microchannel array. Third, the surplus glue is rotated by a spinner at high velocity and exposed to a UV lamp to harden the glue. The micro concave lens molds are then finished and ready to produce convex microlens in poly methsiloxane (PDMS) material. This convex microlens in PDMS can be used for detecting fluorescence in microfluidic channels because a convex microlens plays the light convergence role for optical fiber detection.

Methylenecyclopropanes (MCPs) 1 can react with aldehydes and aldimines to give the corresponding indene, THF, and pyrrolidine cycloaddition products in the presence of BF3·OEt2 under mild reaction conditions.

Ten cultivars of three Brassica species were compared for volatile compounds in hydrated ground seeds that were fungicidal to Rhizoctonia solani AG-4. Among the samples tested, the volatile substances in the ground seed of mustard (Brassica juncea cv. Bau Sin) showed the strongest fungicidal effect. Allyl isothiocyanate was one of the predominant fungicidal compounds detected in the ground seed of all Brassica species tested, and the amount was the highest in ground mustard seed meals. Among the nine carriers tested for seed coating with ground mustard seed meal, Biolan peat B3 was the most effective for the seed treatment. Cabbage seeds treated with a mixture of ground mustard seed meal and Biolan peat B3 (MBF mixture) at 2:3 ratio (w/w) resulted in a significant reduction in incidence of Rhizoctonia damping-off with no harmful effects to the germination of treated seeds. Effective control of Rhizoctonia damping-off of cabbage by the seed treatment with the MBF mixture was also obtained in a large-scale experiment conducted in a commercial automated environment-controlled greenhouse. This study suggests that the MBF mixture has potential for use in the commercial seed treatment.

Automated peritoneal dialysis (APD) and twin-bag (TB) systems are two major peritoneal dialysis (PD) modalities. Published data comparing the infectious complications of these modalities is limited. Subjects and methods. Ninety-five patients using APD (the APD group) and 117 patients using TB system (the TB group) were recruited. Among them, 35 patients used both modalities. The two groups' clinical characteristics, incidences of infectious complications, and the time intervals to first PD-related infection were compared.

Oxygen related defects in Al-containing materials have been determined to degrade luminescence efficiency and reduce carrier lifetime and affect the performance of light emitting diodes and laser diodes utilizing these materials. We have used the;metal-organic source diethylaluminum ethoxide (DEAlO) to intentionally incorporate oxygen-related defects during growth of Al0.5In0.5P by metal-organic vapor phase epitaxy (MOVPE). The incorporated oxygen forms several energy levels in the bandgap with energies of 0.62 eV to 0.89 eV below the conduction band detected using deep level transient spectroscopy. Secondary ion mass spectroscopy measurements of the total oxygen concentration in the layers shows a direct correlation to the measured trap concentrations. Several other energy levels are detected that are not correlated with the oxygen content of the film. The possible origin of these additional levels is discussed.

The AlGaInP/GaP wafer-bonded transparent-substrate (TS) light-emitting diodes (LEDs) have been shown to exhibit luminous efficiencies exceeding many conventional lightning sources including 60 W incandescent sources. This paper will demonstrate the feasibility of scaling wafer bonding technology to 75 mm diameter wafers and some of the unique challenges associated with this scaling. The quality and uniformity of bonding were characterized via scanning acoustic microscopy, white light transmission measurements, full-wafer mapping of parametric performance, and operating life tests. High bonding yields over large areas facilitate low-cost, high-volume fabrication of TS AlGaInP/GaP LEDs, and thus, further enable these devices to compete with other lighting sources.

A model predictive control strategy was developed and tested on a nonlinear canine circulatory model for the regulation of hemodynamic variables under critical care conditions. Different patient conditions such as congestive heart failure, post-operative hypertension, and sepsis shock were studied in closed-loop simulations. The model predictive controller, which uses a different linear model depending on the patient condition, allowed constraints to be explicitly enforced. The controller was initially tuned on the basis of a linear plant model, then tested on the nonlinear physiological model; the simulations demonstrated the ability to handle constraints, such as drug dosage specifications, commonly desired by critical care physicians.

Phytoextraction, a remediation strategy for lead (Pb)‐contaminated soils that removes soil Pb through plant uptake and harvest, may be enhanced by use of synthetic chelates. We evaluated Pb desorption from four contaminated soils (total Pb 1278‐14 349 mg kg −1) by seven chelates (CDTA, DTPA, EDDHA, EGTA, HEDTA, HEIDA, and NTA) at three rates (0.2, 2.0, and 20 mmol chelate kg soil−1) . The three most effective chelates (CDTA, DTPA, and HEDTA) were used in greenhouse studies with an uncontaminated soil and a Pb‐contaminated soil (total Pb = 3212 mg kg−1) to determine the effect of chelate type and rate on growth, Pb uptake, and plant elemental composition. Lead desorption varied with chelate and soil and increased with chelate rate, averaging 948 mg Pb kg−1at the 20 mmol kg−1rate vs. 28 mg Pb kg−1by the control. The general ranking of chelate effectiveness, based on total Pb desorbed, was HEDTA > CDTA > DTPA > EGTA > HEIDA > EDDHA ~ NTA. Plant uptake of Pb from the contaminated soil was enhanced by CDTA, DTPA, and HEDTA, but with even the most effective treatment (corn, high CDTA rate), the amount of Pb extracted by plants was rather low (0.4 kg Pb ha−1). Lead extractable by the Toxicity Characteristic Leaching Procedure) (TCLP) was increased from 9 L−1in the control to from 47 to 174 mg L−1in soils treated with 20 mmol kg−1CDTA or DTPA and chelates generally caused a shift in Pb from resistant to more soluble chemical fractions.

Rhizoctonia solani AG-4 is an important damping-off pathogen of cabbage. Using a baiting technique, R. solani was recovered from the cabbage seeds buried in nine commercial culture media. The frequency of seed colonization by R. solani varied with medium, ranging from 2.5% in Nev-3 to 30% in Floradur A and SI 2; the seeds were examined after being buried for 48 h. Among the five formulated organic compounds tested as amendment for the commercial BVB No. 4 medium, FBN-5A was most effective in controlling damping-off. Although both rates of FBN- 5A, 0.1% and 0.2%, significantly reduced incidence of damping-off, FBN-5A at 0.1% was the more suitable treatment because it not only reduced the disease incidence, but also enhanced the growth of cabbage. The results were confirmed in a large-scale experiment in a commercial automatic environment-controlled greenhouse. This study suggests that the FBN-5A compound offers potential for commercial use as an organic amendment for the management of Rhizoctonia damping-off of vegetable crops.

Oxygen incorporation in AlyIn1−yP (y ∼ 0.5) grown by metalorganic chemical vapor deposition (MOCVD) has been studied as a function of PH3flow, growth temperature, and alloy composition. Both O2and diethylaluminum ethoxide (DEAlO) were employed as sources of oxygen. The incorporation of oxygen was found to be a superlinear function of O2or DEAlO flow. When multiple sources of oxygen are present, a surface interaction leads to enhanced oxygen incorporation. Oxygen incorporation cannot be adequately described by a simple dependence on growth temperature or V/III ratio due to strong interactions between these variables. In Mg-doped AlInP co-doped with oxygen, the incorporation of both Mg and O is strongly affected by an interaction between the two species, and roughly 10% of the oxygen atoms act as compensating donors.

Keywords:hepatic aneurysm; portal vein thrombosis; systemic lupus erythematosus; uraemia

After its first measurement in late August, 1989, the new Na temperature lidar has been in operation during springs 1990 and 1991 at Fort Collins, CO. A total of nine nights (over 2600 profiles) of mesopause temperature measurements, each for a period longer than 4 hours, have been taken. We present these high quality initial profiles which demonstrate the effectiveness of the new two-frequency narrowband lidar technique for mesopause temperature measurements. The average temperature profiles suggest that the spring mesopause temperatures range from 168 K to 205 K. The mesopause heights are around 88 km before the midnight and around 99 km after the midnight. The nightly averaged temperature profiles in the mesopause region display considerable variability. The richness in new geophysical information obtainable with a Na temperature lidar is made evident by noting strong perturbations in a short time scale (15 min) in the data taken on March 11, 1990 and March 18, 1991.

Cattle frequently develop grass tetany when grazing cool-season forages, and the incidence is increased when K concentrations in plants are high. High concentrations of organic acids may also increase the incidence of grass tetany by complexing Mg and Ca. The objective of this experiment was to study the effects of K fertilization on the concentrations of major cations, inorganic anions, and organic acids in cool-season forages. An experiment was conducted in a controlled environmental growth chamber using a mixture of 50% silt loam soil and 50% coarse sand. There were two K levels (0 and 125 mg K kg-1 soil mixture) and three species of cool-season grasses: Linn perennial ryegrass (Lolium perenne L.), Nordan crested wheatgrass (Agropyron desertorum Schultes), and Lincoln smooth bromegrass (Bromus inermis Leysser). Potassium fertilization significantly increased K concentrations and the K/(Ca+Mg) ratios (on a molc kg-1 dry wt. basis), but significantly decreased the concentrations of Mg and Ca in shoots of all species. The addition of K significantly increased the concentrations of aconitic acid in shoots of crested wheatgrass and bromegrass for both harvests. The concentrations of malic acid in shoots of all species, at the first harvest, were markedly increased by K fertilization. However, at the second harvest, the earlier addition of K did not significantly affect the malic acid concentrations in shoots of any of the three species. The concentrations of total organic acids (whether measured directly or indirectly) in shoots of all species were significantly increased by K fertilization at the first harvest, when added K was high in the soil-sand mixture. When cool-season grasses are fertilized with high levels of K and NO3-N, the forage produced is more likely to cause grass tetany in grazing animals.

Low concentrations and low bioavailability of Mg in winter wheat forage have been related to grass tetany, a metabolic disorder of grazing ruminants caused by Mg deficiency in the blood serum. To investigate the effects of root temperature, N form, and Mg supply on Mg uptake and translocation by winter wheat (Triticum aestivum L. 'Centurk'), seedlings were grown in nutrient solution with three root-zone temperatures (RZT) (10, 15, or 20 °C), three N forms (NH4:NO3 in mM 10:0, 5:5, or 0:10), and two Mg levels (0.4 or 4 mM). Increasing the RZT increased Mg uptake rates of seedlings less than 30 days old, but decreased Mg uptake rates for plants more than 30 days old. Magnesium uptake rates were significantly higher for plants supplied only NO3 than for plants supplied only NH4. However, increasing the proportion of NO3 significantly decreased net Mg translocation. Consequently, shoot Mg concentrations at the low Mg level were significantly decreased by increasing the proportion of NO3. As was found for net Mg translocation, net K translocation was significantly decreased by increasing the proportion of NO3. However, net Ca translocation was not significantly affected by the N form. Correlation analysis showed that net Mg translocation was negatively correlated with root K concentrations. The absolute values of the correlation coefficients were increased as the medians of root K concentrations increased. The results indicate that factors inducing an increase in root K concentrations may result in a depression of net Mg translocation from roots to shoots.

The effects of Al on Ca transport could influence Ca accumulation in plants. Low forage Ca concentrations may cause hypocalcemia, a Ca deficiency syndrome of ruminants. Solution culture experiments were conducted in a growth chamber to examine the effects of Al (5–50 μMon uptake and translocation of Ca (45Ca) in winter wheat (Triticum aestivumL.) cultivars (Al‐tolerant Atlas 66 and Al‐sensitive Scout 66). Three‐day‐old seedlings, grown either in a CaCl2solution (0.1 or 1.0 mM) or in a complete‐nutrient solution, were used. For plants grown in CaCl2solution, addition of 5 μMAl significantly decreased Ca uptake and translocation in Scout 66, but not in Atlas 66. Higher levels of Al (20 and 50 μM) decreased Ca uptake and translocation much more in Scout 66 than in Atlas 66. For plants grown in complete‐nutrient solution, Al (5–50 μM) exposure for up to 6 h had little effect on Ca uptake and translocation in either cultivar. This may be due to the reduction in Al3+activities in the external solution, as well as lowered Al3+activities near the root‐cell plasmalemma. When roots were exposed to Al for 24 h, Ca uptake and translocation were decreased significantly in Scout 66, but were little affected in Atlas 66. The percentage of Ca translocated to the shoots was significantly decreased by Al in Scout 66, but not in Atlas 66. These results suggest that Al inhibits both Ca uptake and translocation in Scout 66, but inhibits primarily root Ca uptake in Atlas 66 (and only at higher Al levels). It appears that the use of Al‐tolerant cultivars of wheat forages on acid soils could be important for maintaining proper Ca nutrition of grazing animals.

We report on the identification of a voltage-dependent Ca2+ transport system that mediates Ca2+ influx across the plasma membrane (PM) of wheat (Triticum aestivum) root cells. The experimental approach involved the imposition of transmembrane electrical potentials (via K+ diffusion potentials) in populations of purified, right-side-out PM vesicles isolated from wheat roots. Using 45Ca2+ to quantify Ca2+ influx into the PM vesicles, the voltage-dependent characteristics of Ca2+ transport were found to be similar to those exhibited by L-type voltage-gated Ca2+ channels in animal cells. The putative PM Ca2+ channel opened upon depolarization of the membrane potential, and Ca2+ flux increased to a maximum upon further depolarization and then decreased back to zero upon further successive depolarizations. This channel was found to be selective for Ca2+ over Mg2+, Sr2+, K+, and Na+; was blocked by very low concentrations of La3+; was unaffected by high concentrations of the K+ channel blocker tetraethylammonium; and exhibited Michaelis-Menten-type transport kinetics. Based on these transport properties, we argue that this transport system is a PM Ca2+ channel. We suggest that the use of radiotracer flux analysis of voltage-clamped PM vesicles derived from plant roots is a straightforward approach for the characterization of certain voltage-gated ion channels functioning in cellular membranes of higher plant cells.

Grass tetany, a Mg deficiency syndrome, is a disorder of ruminants grazing grass or cereal forages under certain environmental conditions. A solution culture experiment was conducted to gain a clearer understanding of the nutritional and environmental factors affecting Mg concentrations in winter wheat (Triticum aestivum L.) forage. Effects of N form (NH4/NO3in mM—10:0, 5:5, or 0:10), root‐zone temperature (RZT) (10,15, or 20 °C), and Mg supply (0.4 or 4 mM) on growth and mineral composition of winter wheat forage were investigated. Shoot and root yields were highest for the mixed‐N form, and increased linearly with increasing RZT. Increasing the Mg supply significantly increased Mg concentrations, and decreased Ca concentrations, in both shoots and roots. Concentrations of K and Ca, and estimates of total organic acids significantly increased with increasing proportion of NO3. There was no significant effect of N form on shoot Mg concentrations at the high Mg level. However, at the low Mg level, increasing the proportion of NO3significantly decreased shoot Mg concentrations, producing a forage more likely to cause grass tetany. Ratios of Mg accumulated in shoots to Mg in whole plants were negatively correlated with K concentrations in roots. Correlations with K concentrations in shoots were much lower. Apparently, increasing the K concentration in roots depressed the rate of net Mg translocation from roots to shoots. When Mg in the root zone is low and K is high, increasing the proportion of NO3may decrease shoot Mg concentration and thus increase the likelihood of hypomagnesemia.

Controlled oxygen incorporation in GaAs using Al-0 bonding based precursors, dimethyl aluminum methoxide (DMALO) and diethyl aluminum ethoxide (DEALO), is presented in this investigation. A comparison study of oxygen incorporation kinetics between nominally undoped AlxGa1−xAs using trimethyl aluminum and DMALO-doped GaAs suggests that DMALO is one of the most important oxygen-bearing agents responsible for unintentional oxygen incorporation in AlxGa1−xAs. Controlled oxygen doping using DEALO is reported for the first time. Oxygen incorporation behavior, especially on the effect of the V/III ratio, was found to be quite different from the case of DMALO, mainly due to the differences between methyl- and ethyl-based growth chemistries. Physical, electrical, and optical properties of these oxygen-doped GaAs are also reported.

The defect engineering in metalorganic vapor phase epitaxy InxGa1-xAs and InP by controlled oxygen doping using diethyl aluminum ethoxide (DEALO) was developed in this study. DEALO doping has led to the incorporation of Al and O, and the compensation of shallow Si donors in InxGa1−xAs: Si with 0 ≤ x ≤ 0.25. With the same DEALO mole fraction during growth, the incorporation of Al and O was found to be independent of x, but the compensation of Si donors decreases with increasing In content. Deep level transient spectroscopy analysis on a series of InxGa1-xAs: Si. samples with 0 ≤ x ≤ 0.18 revealed that oxygen incorporation led to a set of deep levels, similar to those found in DEALO doped GaAs. As the In composition was increased, one or more of these deep levels became resonant with the conduction band and led to a high electron concentration in oxygen doped In0.53Ga0.47As. Low temperature photoluminescence emission measurements at 12K on the same set of samples revealed the quenching of the near-band edge peak, and the appearance of new oxygen-induced emission features. DEALO doping in InP has also led to the incorporation of Al and O, and the compensation of Si donors due to oxygen-induced multiple deep levels.

The role of Al interactions with root-cell plasma membrane (PM) Ca2+ channels in Al toxicity and resistance was studied. The experimental approach involved the imposition of a transmembrane electrical potential (via K+ diffusion) in right-side-out PM vesicles derived from roots of two wheat (Triticum aestivum L.) cultivars (Al-sensitive Scout 66 and Al-resistant Atlas 66). We previously used this technique to characterize a voltage-dependent Ca2+ channel in the wheat root PM (J.W. Huang, D.L. Grunes, L.V. Kochian [1994] Proc Natl Acad Sci USA 91: 3473-3477). We found that Al3+ effectively blocked this PM Ca2+ channel; however, Al3+ blocked this Ca2+ channel equally well in both the Al-sensitive and -resistant cultivars. It was found that the differential genotypic sensitivity of this Ca2+ transport system to Al in intact roots versus isolated PM vesicles was due to Al-induced malate exudation localized to the root apex in Al-resistant Atlas but not in Al-sensitive Scout. Because malate can effectively chelate Al3+ in the rhizosphere and exclude it from the root apex, the differential sensitivity of Ca2+ influx to Al in intact roots of Al-resistant versus Al-sensitive wheat cultivars is probably due to the maintenance of lower Al3+ activities in the root apical rhizosphere of the resistant cultivar.

The superconductor MgCNi3, an intermetallic compound with a cubic perovskite crystal structure, was synthesized from Mg, Ni and graphite powders by hybrid microwave heating in a short time. The phases, microstructures and superconductivity were characterized using x-ray diffraction, energy dispersive x-ray analysis, scanning electron microscopy, the standard four-probe method and magnetic measurements. The results indicate that the phases of the synthesized sample are MgCNi3(major phase), a small amount of unreacted graphite and a little MgO. The MgCNi3particle sizes range from two to several microns. The onset superconducting transition temperature of the MgCNi3sample was 6.9 K, and the superconducting transition width was about 0.8 K.

The attempted aza-Baylis−Hillman reaction of N-tosylated imines with ethyl 2,3-butadienoate or penta-3,4-dien-2-one gave azetidine derivatives in the presence of DABCO. In the case of the aza-Baylis−Hillman reaction of N-tosylated imines with ethyl 2,3-butandieonate catalyzed by DMAP, novel dihydropyridine derivatives were formed.

A spectrometer system for studying excited state absorption of ions in crystals is described. Pulsed xenon short arc lamps and keyed photomultipliers are used to measure the transmission after optically pumping the ions into an excited state. A wide dynamic range of absorption coefficients of excited states with lifetimes down to less than 100 μsec can be measured. A repeatability near the shot noise limit is obtained.