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The athletic trainer's (AT) emergency management skill set requires competency in the delivery of basic lifesaving medications. Some lifesaving medications have been a part of athletic training practice for decades, but that list has grown as ATs' practice setting has expanded - increasing the types of em ergent conditions that the AT may have to treat. The 2020 CAATE curricular standards require athletic training students be trained to administer the following: supplemental oxygen, nitroglycerine, low dose aspirin, bronchodilators, epinephrine using automated injection device, glucagon, and naloxone. Clinically, the conditions treated by these medications can be categorized as follows: cardiac, respiratory, hypoglycemia, or anaphylaxis. All ATs should know the indications, contraindications, administration methods, and the details of patient monitoring for each medication. Generally, these medications are safe, have clear indications for use, and few contraindications. While ATs are trained to administer these medications, they must consider state laws and local policies.

The JMH blood group system consists of six high-prevalence antigens. These antigens are located on the Sema7A protein. The molecular basis of the JMH1- phenotype is not known; however, single nucleotide changes in the SEMA7A gene on chromosome 15 account for the other JMH antigens. JMH1, commonly known as JMH, is most notable because transient depression of the antigen occurs and anti-JMH may develop. These antibodies are most commonly observed and are not significant in transfusion. Antibodies developed in the rare JMH variant types may cause reduced red cell survival. This review provides a general overview of the JMH blood group system, including the serologic and molecular characteristics as well as proposed functions of the Sema7A protein.

During explosive movements and potentially injurious situations, the ability to rapidly generate torque is critical. Previous research has suggested that different phases of rate of torque development (RTD) are differentiately controlled. However, the extent to which supraspinal and spinal mechanisms predict RTD at different time intervals is unknown. RTD of the plantarflexors across various phases of contraction (i.e., 0-25, 0-50, 0-100, 0-150, 0-200, and 0-250 ms) was measured in 37 participants. The following predictor variables were also measured: (a) gain of the resting soleus H-reflex recruitment curve; (b) gain of the resting homonymous post-activation depression recruitment curve; (c) gain of the GABAergic presynaptic inhibition recruitment curve; (d) the level of postsynaptic recurrent inhibition at rest; (e) level of supraspinal drive assessed by measuring V waves; and (f) the gain of the resting soleus M wave. Stepwise regression analyses were used to determine which variables significantly predicted allometrically scaled RTD. The analyses indicated that supraspinal drive was the dominant predictor of RTD across all phases. Additionally, recurrent inhibition predicted RTD in all of the time intervals except 0-150 ms. These results demonstrate the importance of supraspinal drive and recurrent inhibition to RTD.

We report a detailed neutron diffraction study of both pinned and moving magnetic Flux Line Lattice (FLL) in NbTa and PbIn samples. In NbTa, the FLL presents a hexagonal lattice even in the absence of current, meanwhile PbIn presents a strongly dislocated phase. In PbIn, dislocations are eliminated by the application of transport current in agreement with theoretical predictions. On the other hand, the absence of curvature of the flux lines for subcritical currents confirm the presence of surface pinning of the FLL.

Small-angle neutron scattering (SANS) is an extremely powerful probe of the vortex state in type II superconductors. The technique may be further enhanced by the use of polarised neutrons and the application of the neutron spin-echo method. We discuss some recent applications of these techniques to the study of both conventional and unconventional superconducting materials, and describe the unique information which SANS can provide on the vortex state. ( 2000 Elsevier Science B.V. All rights reserved.

We have measured an angle-dependent contribution to the equilibrium magnetization of a YBa_2Cu_3O_{7-d} single crystal with columnar defects created by 5.8GeV Pb ions. This contribution manifests itself as a jump in the equilibrium torque signal, when the magnetic field crosses that of the defects. The magnitude of the signal, which is observed in a narrow temperature interval less than 2K and for fields up to about twice the irradiation field, is used to estimate the the energy gained by vortex pinning on the defects. The vanishing of the effective pinning energy at a temperature below Tc is attributed to its renormalization by thermal fluctuations.

There are several ways of investigating#ux lines with polarised neutrons. We shall describe our recent work on IN15 at ILL, investigating spatially varying "elds perpendicular to the #uxoid axes, which are present with tilted "elds in anisotropic superconductors. These "eld components may be detected by polarisation analysis of neutrons di!racted by the #ux line lattice, and allow a detailed investigation of #ux structure in such materials as YBCO and NbSe 2 . A further application of polarised neutrons is the use of neutron spin-echo techniques to measure the speed of moving #ux lines. We have recently demonstrated this in an Nb}Ta alloy on instruments IN11 and IN15, by measuring the energy change of neutrons di!racted by #ux lines, which are moving under the in#uence of a transport current. We shall also comment on others’ work on the search for interference terms between #ux lattice and nuclear di!raction signals, and the use of neutron depolarisation for investigation of #ux distributions in superconductors. ( 1999 Elsevier Science B.V. All rights reserved.

A small angle neutron scattering study of the flux-line lattice in a large untwinned single crystal of ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ is presented. In fields parallel to the $c$ axis, diffraction spots are observed corresponding to four orientations of a hexagonal lattice, distorted by the $a\ensuremath{-}b$ anisotropy. A value for the anisotropy, the penetration depth ratio, of ${\ensuremath{\lambda}}_{a}/{\ensuremath{\lambda}}_{b}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.18\left(2\right)$ was obtained. The high quality of the data is such that second-order diffraction is observed, indicating a well ordered FLL. With the field at 33\ifmmode^\circ\else\textdegree\fi{} to $c$, a field dependent reorientation of the lattice is observed around 3 T.

A neutron small-angle scattering study of the flux-line lattice in heavily twinned YBa2Cu3O72x is presented. It is found that the diffraction signal disappears at temperatures well below Tc , associated with a melting of the flux lattice. The shape of the melting line is consistent with both a Lindemann criterion and the scaling expected for a vortex-glass transition with the superconducting parameters from the three-dimensional XY model. The influence of twin planes on the structure of the vortex lattice and its melting is studied by applying the field at different angles to the c axis. The results are compared with recent specific heat measurements on similar crystals. @S0163-1829~98!03022-7#

The relationship between carrier concentration, structure and composition in Bi 2 Sr 2 CaCu 2 O 8+ δ is amongst the most complex of the high- T c superconducting cuprates. In this paper a number of structural subtleties of the system are discussed based on the results of high-resolution X-ray scattering measurements from single crystals. It is found that the annealing of an oxygen-rich crystal significantly changes the character of certain diffuse scattering features. Accompanying analysis of composition and measurements of T c suggest these changes may be the signature of oxygen ordering which is influential to the superconductivity.

The properties of the incommensurate modulation of Bi-2212 have been investigated using X-ray scattering to observe in situ the response of the structure to high temperature (up to 450°C). The results demonstrate the temperature independent nature of the incommensurability, and several pinning mechanisms which would offer explanations for this are discussed. The strong influence exerted by oxygen diffusion over the structure is also highlighted, and the results clearly indicate the existence of two distinct oxygen diffusion processes. However, it is also found that the wavevector of the modulation is in no way a continuous function of oxygen content; a result contrary to the widespread assumptions in the literature. Only after prolonged annealing was evidence for a structural transition observed, involving the appearance of reflections with an apparently new wavevector of q ≈ 0.14 b ∗ + c ∗ .

The atomic struture of the Bi 2 Sr 2 Ca n−1 Cu n O y high-T c superconductors is distinguished by incommensurate modulations, but their implications for superconductivity are as yet uncertain. Recent studies have suggested a strong invlovement due to the modification of the Cu site environment, and a strong electron lattice interaction would be expected to produce distinct structural changes in the vicinity of T c . This paper presents the first detailed study of the temperature response of the incommensurate modulation in a high quality single crystal of Bi 2 Sr 2 CaCu 2 O y . The x-ray scattering measurements show no evidence of any changes in either the period or the amplitude of the modulation over the temperature range studied (T=200−18K). The results limit any possible structural involvement to distortions with a local ordering of less than 100Ain size. A very small but reproducible decrease in the intensity of Bragg and satellite reflections was noted at ∼140-120K which is suggestive of a minor change in electron distribution.

The measured switched polarization properties of integrated Pb(Zr,Ti)O3 (PZT) capacitors arrays have been found to show a small dependence on individual capacitor size in the range from 0.17 and 100 μm2. These thin (90 nm) PZT capacitors have low voltage switching properties with polarization saturation of

Anti-Vel is an uncommon antibody to a high-prevalence antigen. Its clinical significance and management in the prenatal setting are not well characterized. We present a case that demonstrates the utility of serial prenatal anti-Vel quantitative serologic monitoring with 2-ME serum treatment during pregnancy. The patient is a 23-year-old Hispanic woman with history of prior pregnancy and prior transfusion who was discovered to have an antibody to the high-prevalence Vel antigen in the first trimester (week 7) of her second pregnancy. Interval measurements of the serologic antibody titers were performed during the next 26 weeks. The untreated serum (IgM and IgG) titer increased from a baseline of 4 to 16 during that interval, while the 2-ME (presumed IgG component) titer remained stable at 4. Responding to ultrasound findings suspicious for fetal anemia, the child was delivered without complications at 34 weeks' gestation. At birth, the DAT was negative and there was no evidence of HDN. Placed in the context of other similar reports, this case demonstrates the importance of separately reporting the IgG fraction (after either DTT treatment or 2-ME treatment) from the untreated (IgM and IgG) fraction and the importance of correlating the treated serum titer with potential clinical significance.

To assess the feasibility of employing an ecologically guided childhood obesity relevant surveillance system.Cross-sectional qualitative and quantitative data were collected from 31 organizational representatives across 28 unique organizations and/or departments from three purposively sampled communities in the Capital Health Region in Alberta, Canada.All the organizational representatives surveyed reported awareness of childhood obesity and 36% reported participation in child obesity initiatives. Data to support a surveillance system are available but not in a suitable format, and privacy legislation present significant barriers. Interest in developing and sustaining an ecologically based surveillance system was low (18%).Due to the heterogeneity of available data and limited vision for the development and implementation of a surveillance system, the application of an ecologically based surveillance system relevant to childhood obesity may be constrained. Broad-based awareness of childhood obesity by a wide range of organizations could assist in establishing an effective coalition to address this issue over the long term by supporting the establishment of a surveillance system.

The electrical activation and carrier mobility of InP implanted with the group‐IV elements at MeV energies has been studied as a function of implanted atom (C, Si, Ge, and Sn) and rapid thermal annealing temperature (500–800 °C). In addition, electrical results have been correlated with photoluminescence (PL) measurements. In general, for a dose of 5×1014/cm2 and a projected range of ∼1.0 μm, the electrical activation and carrier mobility increase then saturate with increasing annealing temperature. Similarily, PL emission intensity increases with increasing annealing temperature. At a temperature of 750 °C, the electrically active fraction increases from C, Ge, Si, to Sn, respectively, while carrier mobility and PL emission intensity decreases with increasing atomic mass. Thus, Sn exhibits the highest electrical activation yet lowest carrier mobility with little optically observable, postanneal lattice recovery.

The incidence of weak D has been reported to be between 0.23 and 0.5 percent in Europe and 3.0 percent in the United States. All studies were performed before the introduction of monoclonal anti-D reagents. Using current commercial reagents, this study evaluated D+ samples for the presence of weak D. D+ donors, typed by the Olympus PK 7200, using diluted monoclonal blend anti-D and diluted polyclonal anti-D, were selected by sampling batches of 100 to 200 samples from the previous day's collection. Anti-D reagents used on the Olympus PK 7200 are required to detect RBCs with the weak D phenotype which do not agglutinate at immediate spin (IS) when tested with polyclonal anti-D by manual tube methods. More than 95 percent of donors tested were Caucasian. Using tube tests with two different monoclonal blend anti-D reagents and one polyclonal anti-D typing reagent, the presence or absence of the D antigen was evaluated after the IS reading. Donors found negative or weakly positive (2+) at IS were further typed for weak D by the IAT. The weak D samples were RHD genotyped by allele-specific PCR. Of 1,005 donors tested, 4 (0.4%) were classified as weak D by one or more anti-D reagents. Polyclonal anti-D reagent demonstrated weaker reactions when compared with the monoclonal blends. All weak D samples were found positive for exon 4, intron 4, and exon 10, a finding consistent with most D+ samples. The incidence of weak D found in this study is not significantly different from that found in earlier studies using polyclonal anti-D reagents.

A new high-frequency red cell antigen has been identified and named GIL. GIL differs from all high-frequency antigens included in the International Society of Blood Transfusion classification. There is very little family information and GIL has not been shown to be an inherited character. Five women with anti-GIL have been found. All had been pregnant at least twice. Red blood cells of two of the babies gave positive direct antiglobulin tests, but there were no clinical signs of hemolytic disease. Anti-GIL may have been responsible for a hemolytic transfusion reaction and results of monocyte monolayer assays of two of the anti-GIL suggested a potential to cause destruction of transfused GIL+ RBCs.

Investigation of the specificity of an enzyme-linked immunosorbent assay (ELISA) for detection of Escherichia coli O157:H7 in raw meats (EHEC-Tek; Organon Teknika Corp.) revealed that the target antigens of the detection reagent, monoclonal antibody 4E8C12, were present in numerous serotypes of E. coli and that their ELISA reactivity was influenced by bile salts, acriflavine, and heat. The specificity of the ELISA was improved by a modified test protocol incorporating immunocapture.

A detailed modeling of recently observed nonexponential fluorescence intermittency in colloidal semiconductor quantum dots (QDs) is presented. In particular, experiments have shown that both ``on''-time and ``off''-time probability densities generated from single-QD fluorescence trajectories follow an inverse power law, $P({\ensuremath{\tau}}_{\mathrm{o}\mathrm{n}/\mathrm{o}\mathrm{f}\mathrm{f}})\ensuremath{\propto}1/{\ensuremath{\tau}}_{\mathrm{o}\mathrm{n}/\mathrm{o}\mathrm{f}\mathrm{f}}^{1+\ensuremath{\alpha}},$ over multiple decades in time, where the exponent $1+\ensuremath{\alpha}$ can, in general, differ for ``on'' versus ``off'' episodes. Several models are considered and tested against their ability to predict inverse power law behavior in both $P({\ensuremath{\tau}}_{\mathrm{on}})$ and $P({\ensuremath{\tau}}_{\mathrm{off}}).$ A physical picture involving electron tunneling to, and return from, traps located several nanometers away from the QD is found to be consistent with the observed $P({\ensuremath{\tau}}_{\mathrm{off}})$ but does not yield the inverse power-law behavior seen in $P({\ensuremath{\tau}}_{\mathrm{on}}).$ However, a simple phenomenological model based on exponentially distributed and randomly switched on and off decay rates is analyzed in detail and shown to yield an inverse power-law behavior in both $P({\ensuremath{\tau}}_{\mathrm{on}})$ and $P({\ensuremath{\tau}}_{\mathrm{off}}).$ Monte Carlo calculations are used to simulate the resulting blinking behavior, and are subsequently compared with experimental observations. Most relevantly, these comparisons indicate that the experimental $\mathrm{o}\stackrel{\ensuremath{\rightarrow}}{n}\mathrm{off}$ blinking kinetics are independent of excitation intensity, in contradiction with previous multiphoton models of on/off intermittency based on an Auger-assisted ionization of the QD by recombination of a second electron-hole pair.

Electrical and photoluminescence (PL) measurements have been used to investigate megaelectronvolt implantation of InP with Group-IV elements (C, Si, Ge, and Sn). For a 700 degrees C/10-s rapid thermal annealing cycle, dopant activation increases from C, Ge, Si, to Sn while carrier mobility decreases with increasing implanted ion mass. The former trend suggests that the amphoteric nature of the Group-IV elements and dopant-defect interactions significantly influence relative dopant activation while nonstoichiometry and Fe redistribution have a lesser effect. PL measurements correlate well with the electrical results; overall PL emission intensity increases with increasing annealing temperature and decreasing implanted ion mass. Preliminary results suggest that a peak at approximately 1.65 mu m is associated with a Group-IV element and an implantation-induced defect. >

We report on detailed small-angle neutron scattering measurements with polarization analysis from the flux-line lattice in the anisotropic superconductor ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}.$ When the field was applied at an angle to the principal axes we have observed spin-flip neutron diffraction consistent with local transverse field components. From a detailed study of the angle dependence of the magnitude of the spin-flip neutron-scattered intensity we have found that the transverse-field components are larger than predicted by an anisotropic London model for reasonable mass anisotropy values. The transverse-field components are consistent with a reduced c-axis coherence length at low temperature.

We have used the neutron spin-echo technique to measure the small energy change of neutrons which are diffracted by a moving vortex lattice in a low-pinning Nb-Ta superconducting sample. A transport current was passed in the mixed state to cause flux line movement. In the case of uniform motion, the flux velocity ${\mathbf{v}}_{L}$ was given as expected by the values of electric and magnetic fields, via $\mathbf{E}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}{\mathbf{v}}_{L}\ensuremath{\wedge}\mathbf{B}$. We show that with a nonuniformly moving vortex lattice, one can measure the dispersion of the velocities, opening up new possibilities for investigating moving vortex lines.

Maternal allo-immunization to antigens of the Duffy blood group system can result in haemolytic disease of the newborn (HDN), therefore, the application of allele-specific polymerase chain reaction (ASPCR) for prenatal genotyping of the Duffy antigen system to identify pregnancies at risk for HDN was evaluated. Oligonucleotide primers were designed for ASPCR of FYA, FYB and nullFY alleles. A validation study was performed using DNA isolated from 94 serotyped whole blood samples and 8 amniocentesis samples. A concordance rate of 100 per cent was observed between serotyping and ASPCR detection of the FYA, FYB and nullFY alleles. This assay is particularly useful for rapid genotyping of fetal amniotic cells to identify pregnancies at risk for HDN due to maternal fetal incompatibilities within the Duffy blood group system.

An allele-specific polymerase chain reaction (ASPCR) assay for prenatal genotyping of the Kidd antigen system in order to identify pregnancies at risk for haemolytic disease of the newborn (HDN) was developed. Oligonucleotide primers were designed for ASPCR of JKA and JKB. A validation study was performed using DNA isolated from 54 serotyped whole blood samples and 8 amniocentesis samples. A concordance rate of 100 per cent was observed between serotyping and ASPCR detection of the JKA and JKB alleles. Experiments were conducted to quantify the maternal contamination that could be tolerated in Kidd ASPCR assays. The sensitivity of this assay ranged from 0.2 per cent when detecting the presence of JKB and JKA background, to 2 per cent for detecting the presence of JKA in a JKB background. This sensitive assay is particularly useful for rapid genotyping of fetal amniotic cells to identify pregnancies at risk for HDN due to incompatibilities within the Kidd blood group system.

BACKGROUND: Hospitals and blood centers throughout the United States use a variety of reagents and methods to perform pretransfusion testing. A survey was developed to determine the reagents and methods in use and their relative prevalence in different work settings. STUDY DESIGN AND METHODS: A national survey on pretransfusion testing was conducted. Surveys were distributed to state and regional blood bank associations, which then distributed them to hospitals and blood centers within their region. In most instances, the blood centers distributed the survey to the local hospitals. Completed surveys were returned to the authors for review, and all information was entered into a database for analysis. RESULTS: Analysis of the data shows that the majority of blood banks use monoclonal reagents for ABO testing and monoclonal-polyclonal blended reagents for Rh testing. The data show that anti-lgG and polyclonal anti-human globulin reagents are used almost equally for antibody screening (detection) tests and that most blood banks use a three-cell antibody-screening test. Slightly more than 50 percent of hospitals use an immediate-spin crossmatch in the absence of unexpected antibodies. CONCLUSION: A number of approved reagents and methods are used by blood bank laboratories for pretransfusion testing. Facility size (number of beds) and type tend to influence the choice of methods and reagents employed. This survey provides an opportunity for Mood bank laboratories to compare their current practices with those of their peers.

A 75-year-old woman taking the nonsteroidal anti-inflammatory drug diclofenac (DCF) presented with acute Coombs-positive hemolytic anemia and subsequently developed renal failure. A drug-dependent antibody specific for red blood cells (RBCs) could not be demonstrated by in vitro testing with DCF. However, her serum was found to contain an IgM antibody that reacted strongly with RBCs in the presence of urine from any of four subjects who had ingested DCF. The active substance in urine was isolated, subjected to high-performance liquid chromatographic (HPLC) analysis, and found to be a glucuronide conjugate of a known DCF metabolite, 4'-hydroxydiclofenac (4'-OH DCF). Negative results were obtained with four other DCF metabolites. Two 4'-OH DCF glucuronides were synthesized in vitro using a liver microsomal system. One promoted agglutination of normal RBCs by the patient's serum and was identified as the glucuronide ester of 4'-OH DCF by proton nuclear magnetic resonance (NMR) analysis. Studies with a panel of RBCs showed that the patient's antibody reacted preferentially with the e antigen of the Rh system. Acute immune hemolytic anemia in this patient appears to have been caused by sensitization to DCF modified by 4' hydroxylation and glucuronidation. This is the first reported example of immune cytopenia caused by sensitivity to a glucuronide conjugate of a drug metabolite. Since glucuronidation is a common pathway of drug metabolism, studies of the frequency with which glucuronide derivatives of primary medications cause immune cytopenia seem warranted.

Oral inoculation of calves and steers with 10(10) CFU of Escherichia coli O157:H7 induced prompt and sustained increases in serum antibodies to O157 lipopolysaccharide. Neutralizing antibodies to verotoxin 1 also increased rapidly in most steers but more gradually in calves. None of the animals developed neutralizing antibodies to verotoxin 2. These serological responses were not correlated with elimination of infection in calves or steers or protection of calves against reinfection with the same strain.

Interaction matrices provide a framework in which to set technical and commercial objectives for contaminated land remediation. From that framework stem questions for investigating the site and for the treatment and redevelopment options. The paper introduces the use of these interaction matrices in this context, in particular as a tool to support risk assessment.

Extensive efforts have been made in recent years in the U.K. to recycle contaminated land for further beneficial use. The remedial treatment of this land often involves the application of engineering, science and technology set within planning, legal, contractual and social frameworks. However, rapid expansion of the knowledge base and the variety of remediation techniques now available can inhibit their adoption into practice. Collaborative information projects which explain these issues are effective and economical in speeding the transfer of R&D advances into practice. A major programme of research and guidance information on derelict and contaminated land is described and key areas of decommissioning and demolition, planning, site investigation and risk assessment, selection of, and options for, treatment are discussed.

Appropriate postpartum administration of Rh immune globulin relies on sensitive detection and accurate quantitation of fetomaternal hemorrhage (FMH). Recently, the microscopic Du test (micro Du) enhanced with polyethylene glycol (PEG Du) and flow cytometry (FC) have been advocated for this purpose. Three qualitative methods (micro Du, rosette test, and PEG Du) and two quantitative methods (acid elution and FC) for assessing FMH were evaluated with particular attention given to PEG Du and FC. In vitro studies comprised 10 series of dilutions of D+ cord cells in D- adult cells to yield D+ cell concentrations of 0.06, 0.12, 0.25, 0.50, 0.75, 1.0, and 2.0 percent. Additionally, 26 postpartum samples were tested. Of the qualitative techniques, the micro Du test was the least sensitive with 20 percent false-negative results occurring at 0.5 percent fetal cells. The PEG Du test was only slightly more sensitive and offered no clinical advantage. The rosette test was the most sensitive, consistently detecting fetal cells at concentrations of 0.25 percent or greater. FC and acid elution showed similar results, with good correlation obtained between measured and expected quantities of fetal cells (r = 0.99 and 0.96, respectively). One of 26 postpartum samples was positive by all screening techniques; acid elution and FC detected 0.3-percent concentrations of fetal cells and 0.17-percent concentrations of D+ cells, respectively. Although acid elution is a more commonly used method for quantitating FMH, FC offers an acceptable alternative that is capable of analyzing large numbers of cells with objectivity and reproducibility.

Inconsistency in the returns of sugar percentages from the factories has often perplexed growers and has at times given rise to some mistrust of the analytical procedure. Consignments of beet lifted on the same day and from the same field have been credited by the factory with widely different sugar contents. This has occurred within the writer's experience, even though the precaution was taken of loading the cart loads of beet into two trucks alternately, thereby eliminating any possibility of one truck being filled with beet from a better part of the field than the other.

The implantation temperature dependence of dopant solubility and electrical activity was investigated for Sn, Cd and Te ions in GaAs. Implantation doses of 5×1012 – 5×1015 cm−2 were performed in the temperature range from LN2 to 400°C, followed by rapid thermal annealing (950°C) or furnace annealing between 650°C and 850°C. Solubilities above 1020 cm−3 were obtained for all of the species, with a peak value of 2.5×1021 cm−3 for Te after 850°C furnace annealing. However essentially no correlation existed between dopant solubility and electrical activity or between electrical activity and the high density of defects remaining after many of the annealing cycles. This emphases the role of fine scale, point defect complexes in controlling the electrical activity of implanted dopants in GaAs.