Comparison of Relative Bias, Precision, and Efficiency of Sampling Methods for Natural Enemies of Soybean Aphid (Hemiptera: Aphididae).

Generalist natural enemies play an important role in controlling soybean aphid, Aphis glycines (Hemiptera: Aphididae), in North America. Several sampling methods are used to monitor natural enemy populations in soybean, but there has been little work investigating their relative bias, precision, and efficiency. We compare five sampling methods: quadrats, whole-plant counts, sweep-netting, walking transects, and yellow sticky cards to determine the most practical methods for sampling the three most prominent species, which included Harmonia axyridis (Pallas), Coccinella septempunctata L. (Coleoptera: Coccinellidae), and Orius insidiosus (Say) (Hemiptera: Anthocoridae). We show an important time by sampling method interaction indicated by diverging community similarities within and between sampling methods as the growing season progressed. Similarly, correlations between sampling methods for the three most abundant species over multiple time periods indicated differences in relative bias between sampling methods and suggests that bias is not consistent throughout the growing season, particularly for sticky cards and whole-plant samples. Furthermore, we show that sticky cards produce strongly biased capture rates relative to the other four sampling methods. Precision and efficiency differed between sampling methods and sticky cards produced the most precise (but highly biased) results for adult natural enemies, while walking transects and whole-plant counts were the most efficient methods for detecting coccinellids and O. insidiosus, respectively. Based on bias, precision, and efficiency considerations, the most practical sampling methods for monitoring in soybean include walking transects for coccinellid detection and whole-plant counts for detection of small predators like O. insidiosus. Sweep-netting and quadrat samples are also useful for some applications, when efficiency is not paramount.

Molecular determinants of state-dependent block of Na+ channels by local anesthetics.

Sodium ion (Na+) channels, which initiate the action potential in electrically excitable cells, are the molecular targets of local anesthetic drugs. Site-directed mutations in transmembrane segment S6 of domain IV of the Na+ channel alpha subunit from rat brain selectively modified drug binding to resting or to open and inactivated channels when expressed in Xenopus oocytes. Mutation F1764A, near the middle of this segment, decreased the affinity of open and inactivated channels to 1 percent of the wild-type value, resulting in almost complete abolition of both the use-dependence and voltage-dependence of drug block, whereas mutation N1769A increased the affinity of the resting channel 15-fold. Mutation I1760A created an access pathway for drug molecules to reach the receptor site from the extracellular side. The results define the location of the local anesthetic receptor site in the pore of the Na+ channel and identify molecular determinants of the state-dependent binding of local anesthetics.

Isolation of O1 serovars of Vibrio cholerae from water by serologically specific method.

Vibrio cholerae bacteria of the serological variety O1 were consistently isolated from water samples by passing the water with added Tween 20 through columns packed with polystyrene beads coated with antibodies against the O1 antigenic determinants. The beads from the columns were washed, transferred to alkaline peptone broth, and incubated. The O1 serovars were isolated and identified by established procedures.

Within-plant distribution of soybean aphid (Hemiptera: Aphididae) and development of node-based sample units for estimating whole-plant densities in soybean.

The soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), is capable of reducing soybean, Glycine max (L.) Merr., yield up to 40% during severe outbreaks. Frequent sampling, which can be costly and time-consuming, is essential to making informed management decisions. However, one way to decrease sampling effort is to use a reduced sample unit when possible. The objectives of this study were to describe the vertical distribution of soybean aphid within soybean over time and to define node-based sample units of varying sizes by testing the ability of selected units to accurately estimate whole-plant aphid density. Within-plant distribution of soybean aphid changed significantly with time. However, the average nodal position where soybean aphids were found on soybean remained within the top half of the plant at all three locations studied across all sample dates. Consequently, selecting the node with the highest aphid density multiplied by the total number of infested nodes (N(MAX)') was the best predictor of aphids on remaining soybean components in both the original (r2 = 0.855) and validation (r2 = 0.824) data sets. For sample units that included more than a single node to estimate densities, a weighted formula, which incorporated changes observed in the within-plant aphid distribution, improved model performance (higher r2 values) and reduced variability around parameter estimates compared with a node-averaged formula. Our results suggest that smaller sample units provide reliable estimations of whole-plant aphid density throughout the growing season for differently maturing soybean, which is essential to their use in pest management decisions and development of future sampling plans.

Economic threshold for soybean aphid (Hemiptera: Aphididae).

Soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), reached damaging levels in 2003 and 2005 in soybean, Glycine max (L.) Merrill, in most northern U.S. states and Canadian provinces, and it has become one of the most important pests of soybean throughout the North Central region. A common experimental protocol was adopted by participants in six states who provided data from 19 yield-loss experiments conducted over a 3-yr period. Population doubling times for field populations of soybean aphid averaged 6.8 d +/- 0.8 d (mean +/- SEM). The average economic threshold (ET) over all control costs, market values, and yield was 273 +/- 38 (mean +/- 95% confidence interval [CI], range 111-567) aphids per plant. This ET provides a 7-d lead time before aphid populations are expected to exceed the economic injury level (EIL) of 674 +/- 95 (mean +/- 95% CI, range 275-1,399) aphids per plant. Peak aphid density in 18 of the 19 location-years occurred during soybean growth stages R3 (beginning pod formation) to R5 (full size pod) with a single data set having aphid populations peaking at R6 (full size green seed). The ET developed here is strongly supported through soybean growth stage R5. Setting an ET at lower aphid densities increases the risk to producers by treating an aphid population that is growing too slowly to exceed the EIL in 7 d, eliminates generalist predators, and exposes a larger portion of the soybean aphid population to selection by insecticides, which could lead to development of insecticide resistance.

A simple method for in-field sex determination of the multicolored Asian lady beetle Harmonia axyridis.

The multicolored Asian lady beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), has become a popular study organism due to its promise as a biological control agent and its potential adverse, non-target impacts. Behavioral and ecological research on H. axyridis, including examinations of its impacts, could benefit from non-destructive or non-disruptive sexing techniques for this coccinellid. External morphological characters were evaluated for H. axyridis (succinea color form) sex determination in laboratory and field studies. The shape of the distal margin of the fifth visible abdominal sternite accurately predicted H. axyridis sex for all beetles examined. Males consistently had a concave distal margin, while females had a convex distal margin. In addition, pigmentation of the labrum and prosternum were both significantly associated with H. axyridis sex; males had light pigmentation and females had dark pigmentation. Labrum and prosternum pigmentation increased from light to dark with decreasing rearing temperature and increasing time after adult eclosion for females. Male pigmentation was only affected by a decrease in rearing temperature. Validation through in-field collections indicated that these predictors were accurate. However, labrum pigmentation is a more desirable character to use to determine sex, because it is more accurate and easily accessible. Therefore, we recommend using labrum pigmentation for in-field sex determination of H. axyridis. Implications of this diagnostic technique for applied and basic research on this natural enemy are discussed.

High conductance sustained single-channel activity responsible for the low-threshold persistent Na(+) current in entorhinal cortex neurons.

Stellate cells from entorhinal cortex (EC) layer II express both a transient Na(+) current (I(Na)) and a low-threshold persistent Na(+) current (I(NaP)) that helps to generate intrinsic theta-like oscillatory activity. We have used single-channel patch-clamp recording to investigate the Na(+) channels responsible for I(NaP) in EC stellate cells. Macropatch (more than six channels) recordings showed high levels of transient Na(+) channel activity, consisting of brief openings near the beginning of depolarizing pulses, and lower levels of persistent Na(+) channel activity, characterized by prolonged openings throughout 500 msec long depolarizations. The persistent activity contributed a noninactivating component to averaged macropatch recordings that was comparable with whole-cell I(NaP) in both voltage dependence of activation (10 mV negative to the transient current) and amplitude (1% of the transient current at -20 mV). In 14 oligochannel (less than six channels) patches, the ratio of transient to persistent channel activity varied from patch to patch, with 10 patches exhibiting exclusively transient openings and one patch showing exclusively persistent openings. In two patches containing only a single persistent channel, prolonged openings were observed in >50% of test depolarizations. Moreover, persistent openings had a significantly higher single-channel conductance (19.7 pS) than transient openings (15.6 pS). We conclude that this stable high-conductance persistent channel activity is responsible for I(NaP) in EC stellate cells. This persistent channel behavior is more enduring and has a higher conductance than the infrequent and short-lived transitions to persistent gating modes that have been described previously in brain neurons.

Persistent sodium channel activity mediates subthreshold membrane potential oscillations and low-threshold spikes in rat entorhinal cortex layer V neurons.

Entorhinal cortex layer V occupies a critical position in temporal lobe circuitry since, on the one hand, it serves as the main conduit for the flow of information out of the hippocampal formation back to the neocortex and, on the other, it closes a hippocampal-entorhinal loop by projecting upon the superficial cell layers that give rise to the perforant path. Recent in vitro electrophysiological studies have shown that rat entorhinal cortex layer V cells are endowed with the ability to generate subthreshold oscillations and all-or-none, low-threshold depolarizing potentials. In the present study, by applying current-clamp, voltage-clamp and single-channel recording techniques in rat slices and dissociated neurons, we investigated whether entorhinal cortex layer V cells express a persistent sodium current and sustained sodium channel activity to evaluate the contribution of this activity to the subthreshold behavior of the cells. Sharp-electrode recording in slices demonstrated that layer V cells display tetrodotoxin-sensitive inward rectification in the depolarizing direction, suggesting that a persistent sodium current is present in the cells. Subthreshold oscillations and low-threshold regenerative events were also abolished by tetrodotoxin, suggesting that their generation also requires the activation of such a low-threshold sodium current. The presence of a persistent sodium current was confirmed in whole-cell voltage-clamp experiments, which revealed that its activation "threshold" was negative by about 10mV to that of the transient sodium current. Furthermore, stationary noise analysis and cell-attached, patch-clamp recordings indicated that whole-cell persistent sodium currents were mediated by persistent sodium channel activity, consisting of relatively high-conductance ( approximately 18pS) sustained openings. The presence of a persistent sodium current in entorhinal cortex layer V cells can cause the generation of oscillatory behavior, bursting activity and sustained discharge; this might be implicated in the encoding of memories in which the entorhinal cortex participates but, under pathological situations, may also contribute to epileptogenesis and neurodegeneration.

Functional modulation of human brain Nav1.3 sodium channels, expressed in mammalian cells, by auxiliary beta 1, beta 2 and beta 3 subunits.

Voltage-gated sodium channels consist of a pore-forming alpha subunit and two auxiliary beta subunits. Excitable cells express multiple alpha subtypes, designated Na(v)1.1-Na(v)1.9, and three beta subunits, designated beta1, beta2 and beta3. Understanding how the different alpha subtypes, in combination with the various beta subunits, determine sodium channel behavior is important for elucidating the molecular basis of sodium channel functional diversity. In this study, we used whole-cell electrophysiological recording to examine the properties of the human Na(v)1.3 alpha subtype, stably expressed in Chinese hamster ovary cells, and to investigate modulation of Na(v)1.3 function by beta1, beta2 and beta3 subunits. In the absence of beta subunits, human Na(v)1.3 formed channels that inactivated rapidly (tau(inactivation) approximately equals 0.5 ms at 0 mV) and almost completely by the end of 190-ms-long depolarizations. Using an intracellular solution with aspartate as the main anion, the midpoint for channel activation was approximately -12 mV. The midpoint for inactivation, determined using 100-ms conditioning pulses, was approximately -47 mV. The time constant for repriming of inactivated channels at -80 mV was approximately 6 ms. Coexpression of beta1 or beta3 did not affect inactivation time course or the voltage dependence of activation, but shifted the inactivation curve approximately 10 mV negative, and slowed the repriming rate ca. three-fold. beta2 did not affect channel properties, either by itself or in combination with beta1 or beta3. Na(v)1.3 expression is increased in damaged nociceptive peripheral afferents. This change in channel expression levels is correlated with the emergence of a rapidly inactivating and rapidly repriming sodium current, which has been proposed to contribute to the pathophysiology of neuropathic pain. The results of this study support the hypothesis that Na(v)1.3 may mediate this fast sodium current.

Effect of tumor necrosis factor alpha on rabbit corneal endothelial permeability.

PURPOSE: Tumor necrosis factor alpha (TNF alpha) is present in the iris and the lacrimal gland, and its concentration is increased during inflammation and after corneal wounding. Although TNF alpha has been shown to increase keratocyte and corneal epithelial interleukin production, no definitive effects of TNF alpha on corneal endothelial cells have been reported. TNF alpha has been shown to disrupt barrier function in vascular endothelial monolayers through f-actin depolymerization. A reduction in intracellular cyclic adenosine monophosphate (cAMP) concentration may play a role in this response. This study was designed to examine the role and signal transduction mechanisms of TNF alpha modulation of endothelial permeability in the cornea. In addition, it is the first examination of the effects of TNF alpha on the barrier function of a noncultured cell monolayer. METHODS: Rabbit corneal endothelial superfusions were performed under an in vitro specular microscope. Corneas were processed for permeability measurements or f-actin staining. RESULTS: TNF alpha superfused corneas had significantly higher permeabilities than controls. f-actin staining revealed that TNF alpha superfusion disrupted f-actin filaments when compared to controls. Corneas superfused with the f-actin stabilizing agent phallacidin had significantly lower permeabilities than TNF alpha superfused pairs. Permeabilities of corneas superfused with TNF alpha plus 8-bromo-cAMP (0.01 to 3 mM) were significantly lower than TNF alpha superfused pairs at all concentrations, although only significantly lower at the 0.1 mM cAMP concentration. CONCLUSIONS: TNF alpha causes an increase in corneal endothelial permeability, and this increase is mediated by disruption of f-actin filaments; cAMP appears to be involved in this response.

Combination therapy that targets secondary pulmonary changes after abdominal trauma.

After abdominal trauma, the lung is susceptible to secondary injury caused by acute neutrophil (PMN) sequestration and alveolar capillary membrane disruption. Adenosine is an endogenous anti-inflammatory metabolite that decreases PMN activation. AICAR ([5-amino-1-[beta-D-ribofuranosyl]imidazole-4-carboxamide]riboside) is the prototype of a novel class of anti-inflammatory drugs that increase endogenous adenosine. After trauma, AICAR administration has been shown to decrease secondary lung injury in models of hemorrhagic shock with delayed lipopolysaccharide challenge and pulmonary contusion. However, early suppression of PMN activation could worsen outcomes after penetrating abdominal trauma. We hypothesized that, after penetrating abdominal trauma, the ideal resuscitation strategy would involve early, short-lived suppression of PMN activation to minimize secondary lung injury, followed by later enhancement of PMN chemotaxis and phagocytosis [using granulocyte colony-stimulating factor (G-CSF)] to lessen late septic complications. G-CSF has not been shown to potentiate PMN mediated pulmonary reperfusion injury. Swine were subjected to cecal ligation/incision and hemorrhagic shock (trauma), followed by resuscitation with shed blood, crystalloid, and either G-CSF, a combination of G-CSF and AICAR, or 0.9% normal saline. At 72 h, bronchoalveolar lavage (BAL) leukocyte counts and protein concentration were determined, and lung tissue analysed for myeloperoxidase (MPO, a measure of PMN infiltration) and microscopic pathology. Analysis of BALs revealed a significant increase protein concentrations and in white blood cell and PMN infiltration (P< 0.05) following trauma. These acute changes were not exacerbated by G-CSF, but were reversed by combined AICAR + G-CSF, which implicates a physiologic role for adenosine. This suggests that combination therapy may have beneficial effects on the lung after trauma.

Effect of transfusion on physiologic changes after resuscitated trauma.

BACKGROUND: The purpose of this experimental study was to test whether transfusion potentiated physiologic changes associated with fluid resuscitated trauma in controlled conditions. METHODS: Anesthetized and ventilated mongrel pigs were subjected to soft-tissue injury plus 35% hemorrhage and 1 hour shock and then were resuscitated with either autologous (shed) or heterologous (cross-transfused) fresh whole blood. Leukocyte differential counts, T-lymphocyte subsets, neutrophil adherence molecule (CD18) expression, granulocyte oxidative burst, plasma cortisol, and serum chemistries were monitored in awake animals with indwelling catheters on 3 consecutive days. Changes were referenced to preinjury baseline values and to a control group that received heterologous transfusion but no shock. To determine whether these changes might have influenced host defense, a low-dose challenge with Escherichia coli endotoxin (lipopolysaccharide [LPS]; 1 to 2 micrograms/kg for 30 minutes) was administered on day 4. RESULTS: During recovery, neutrophil counts, neutrophil CD18 expression, and granulocyte oxidative burst were generally increased, but the changes were not potentiated by transfusion. Lymphocyte subpopulations remained relatively constant. Serum enzyme markers were elevated with trauma plus shed blood or trauma plus cross-transfusion, but they remained essentially unchanged after heterologous transfusion only. Plasma cortisol, a nonspecific index of stress, peaked at 3 to 6 times higher than baseline. The increases tended to be higher and later with heterologous transfusion only, relative to trauma plus shed blood or trauma plus cross-transfusion. The delayed LPS challenge evoked profound but transient pulmonary hypertension and leukopenia, followed by subsequent hypoxemia; the time courses and magnitude of these changes were similar in all groups. CONCLUSIONS: If these measured variables before and after LPS challenge are a valid index of host defense in this species, then a 35% transfusion does not potentiate the risk for posttrauma immune dysfunction when the magnitude of injury is constant. Thus the predisposition to infection after human trauma might be due to cold storage of blood; separation of blood into components, or other transfusion-related practices rather than to transfusion per se.

Granulocyte colony-stimulating factor and neutrophil-related changes in local host defense during recovery from shock and intra-abdominal sepsis.

BACKGROUND: We have reported that treatment with exogenous granulocyte colony-stimulating factor (G-CSF) improves abscess localization and reduces mortality without aggravating neutrophil (PMN)-mediated reperfusion injury in a model of septic abdominal trauma. The purpose of this study was to determine actions of G-CSF on PMN function in the peritoneum. METHODS: Anesthetized swine were pretreated with broad-spectrum antibiotics and underwent cecal ligation and incision and 35% hemorrhage (trauma). After 1 hour they were resuscitated with shed blood, crystalloid, and either G-CSF (n = 10) or saline solution vehicle (n = 9). The animals were observed for 72 hours. RESULTS: After trauma, saline solution treatment increased PMN infiltration into the peritoneum within 2 hours (P = .035), increased peritoneal PMN elastase production (i.e., cytotoxicity) by 24 hours (P = .004), and decreased adherence of peritoneal PMNs to an artificial substrate from 4 to 72 hrs (P = .043). The mean autopsy score was 7.0 +/- 0.5. With G-CSF treatment peritoneal neutrophilia was enhanced (maximum 48 hours, P = .002) and PMN cytotoxicity was augmented and delayed (maximum 48 hours, P = .004). Despite these changes, adherence of peritoneal PMNs was not significantly changed and there was no evidence for PMN-mediated damage in the lung as judged by bronchoalveolar lavage protein, bronchoalveolar lavage PMNs, lung tissue myeloperoxidase, or histologic changes. The mean autopsy score was improved to 4.1 +/- 0.3 (P < .001). CONCLUSIONS: G-CSF in resuscitation fluids improved localization of an intra-abdominal septic focus by increased production of circulating PMNs, increased PMN extravasation into the peritoneal cavity, and increased PMN cytotoxicity at the abdominal septic focus, without exaggerating PMN-dependent reperfusion injury in the lung. Therefore these data further support the idea that G-CSF in resuscitation fluids might reduce septic complications in the multiply injured trauma patient.

Transient inhibition of CD18-dependent leukocyte functions after hemorrhage and polymicrobial sepsis.

BACKGROUND: The goals were (1) to characterize physiologic changes after a combined insult of hemorrhage plus sepsis in a large animal model and (2) to determine whether transient inhibition of the neutrophil CD18 adherence receptor during fluid resuscitation impairs host defense during recovery from this injury. METHODS: Two series of experiments were performed in anesthetized swine. In the first series (n = 22), the cecum was ligated and incised immediately before 35% hemorrhage. After 1 hour, shed blood plus supplemental fluid was administered to restore and stabilize hemodynamics. On the basis of these results, a second series examined effects of anti-CD18 (2 mg/kg R15.7; n = 9) or its saline placebo (n = 10) administered during fluid resuscitation. RESULTS: In the first series the mortality rate was 41% (9 of 22). Early deaths occurred 3.0 +/- 0.8 days after injury and were distinguished by significantly lower neutrophil counts on resuscitation. Those alive a 7 days had intraabdominal abscesses and bacteremia. Alveoli and peribronchial spaces were congested, with edema and fibrin deposition in capillaries and alveoli. Livers were congested with biliary stasis. Despite these pathologic findings, hemodynamic, electrolyte, and serum enzyme changes were minimal. In the second series the mortality rate at 4 days was 30% with placebo (3 of 10) versus 33% with anti-CD18 (3 of 9). Lung changes (i.e., pneumonia, pleuritis, thrombosis, and edema) were similar in both groups, but liver congestion and hemorrhage were attenuated by anti-CD18. Some aspects of host defense were altered by anti-CD18. At 24 and 48 hours the oxidative burst potential for circulating granulocytes was 208% +/- 57% and 383% +/- 73% with placebo versus 1273% +/- 351% and 762% +/- 226% in anti-CD18. At 72 hours the granularity of circulating neutrophils was unchanged from baseline with placebo but was reduced to 82% +/- 5% by anti-CD18. At 48 hours lipopolysaccharide-evoked tumor necrosis factor production in vitro was reduced to 62% +/- 22% with placebo but was increased to 148% +/- 16% with anti-CD18. CONCLUSIONS: Anti-CD18 during fluid resuscitation did not increase vulnerability to endogenous pathogens because the transient inhibition of neutrophil demargination was balanced by enhanced oxidative burst, degranulation, and production of tumor necrosis factor in circulating cells later during recovery. Thus a single administration of antiadhesion therapy does not worsen posttrauma outcome even if given during ongoing sepsis.

A call for help: collaborative nursing research.

Key issues related to HIV nursing research are the focus of this literature review. Results of two prior literature reviews are combined with the author's current review to serve as a basis for discussion. Findings indicate that further research is needed, particularly in the area of physiological responses to nursing care. Collaboration between clinicians and researchers is viewed as the most effective way to conduct HIV nursing research. Suggestions related to ways of facilitating collaborative research are discussed.

Work-related activities to improve quality of life in HIV disease.

The authors conducted an ethnographic analysis of various ways that persons with AIDS (PWAs) manage their illness in order to improve quality of life. According to Anselm Strauss (1975), illness management involves "work": The activities associated with work change as disease-related symptomatology presents different responses. Strauss' concept of work served as the theoretical orientation for this study. The researchers interviewed the respondents (N = 19) while they were hospitalized for problems related to their diagnosis of AIDS. Analysis was guided by grounded theory. Several categories of management activities emerged. The participants perceived all work-related activities as very important to life in the hospital. They perceived nurses as confederates who were involved in many of the work activities. Quality of life was enhanced when PWAs were able to conduct activities they felt were important and when the healthcare team supported their work.

Health locus of control among HIV-positive indigent women.

The authors explored the multidimensional construct of health locus of control among 14 indigent HIV-positive women who attended one of two southwestern city health clinics. An exploratory survey design was used to compare the mean responses of the subjects on the Multidimensional Health Locus of Control (MHLC) Scales with established normative data. The women believed they had control over their health, yet felt powerful others and chance determine their health outcomes. These findings are drawn from high scores on both the Internal and External MHLC Scales. Findings imply that these women may not view themselves as having any control in the dichotomous world of acute and chronic illness. Authors recommend that nurses should encourage their patients to participate in the management of their health care.

Demography of soybean aphid (Homoptera: Aphididae) at summer temperatures.

Soybean aphid, Aphis glycines Matsumura, is now widely established in soybean, Glycine max L., production areas of the northern United States and southern Canada and is becoming an important economic pest. Temperature effect on soybean aphid fecundity and survivorship is not well understood. We determined the optimal temperature for soybean aphid growth and reproduction on soybean under controlled conditions. We constructed life tables for soybean aphid at 20, 25, 30, and 35 degrees C with a photoperiod of 16:8 (L:D) h. Population growth rates were greatest at 25 degrees C. As temperature increased, net fecundity, gross fecundity, generation time, and life expectancy decreased. The prereproductive period did not differ between 20 and 30 degrees C; however, at 30 degrees C aphids required more degree-days (base 8.6 degrees C) to develop. Nymphs exposed to 35 degrees C did not complete development, and all individuals died within 11 d. Reproductive periods were significantly different at all temperatures, with aphids reproducing longer and producing more progeny at 20 and 25 degrees C than at 30 or 35 degrees C. Using a modification of the nonlinear Logan model, we estimated upper and optimal developmental thresholds to be 34.9 and 27.8 degrees C, respectively. At 25 degrees C, aphid populations doubled in 1.5 d; at 20 and 30 degrees C, populations doubled in 1.9 d.

Enumerative and binomial sequential sampling plans for soybean aphid (Homoptera: Aphididae) in soybean.

Since the discovery of the soybean aphid, Aphis glycines Matsumura, in midwestern U.S. soybean, Glycine max L., in 2000, the aphid has become a significant economic pest. Basic information about estimating population density within fields is unknown. Therefore, we developed two sampling plans to efficiently characterize A. glycines densities. Enumerative and binomial sequential plans were developed using 89 data sets collected from 10 commercial fields sampled during 2001-2003. Re-sampling software was used to validate the enumerative plan on whole plant counts, based on Taylor's power law parameters (a = 9.157 and b = 1.543). For research applications, the enumerative plan was modified to provide an actual precision level of 0.10 (SE/mean), which resulted in an average sample number of 310 individual plants. For integrated pest management (IPM) purposes, we developed an enumerative plan with an actual precision of 0.25, which resulted in an average sample number of 38 individual plants. For IPM applications, the binomial plan will likely be more practical. Binomial plans were developed using two tally thresholds at five action thresholds. Final analysis of the operating characteristic curve for each plan indicated that the tally threshold of > or = 40 aphids per plant, and an action threshold of 0.837 (84% of the plants infested) provided the most correct treat (4%) and no-treat (95%) decisions, with very low incorrect treat (0.5%) and no-treat (0.5%) decisions. A tally threshold of > or = 40 aphids per plant and action thresholds of 84% of plants infested is equivalent to a mean density of 250 aphids per plant, a recently recommended economic threshold. Using this threshold, the minimum required sample number for the binomial plan was 11 plants.

The significant other's role in improving quality of life in persons with AIDS dementia complex.

This article contains a description of how social support systems criteria can be used by nurses as a framework to include significant others in the care of their loved ones with AIDS. Nursing care parameters are identified to facilitate mutual planning among persons with AIDS dementia complex, their significant others and nurses throughout disease progression. Incorporation of the nursing intervention protocols will improve quality of life by preparing for possible alterations in mental status should dementia occur. A case study is presented to illustrate use of the intervention protocol.