Affirming Hormone Treatment for a Transgender Adolescent After a Venous Thromboembolic Event.

BACKGROUND: Medical affirmation, including gender-affirming hormones, is an essential component in the treatment of many transgender and gender-diverse youth. The risk of venous thromboembolism (VTE) during testosterone therapy for gender-affirming care is not fully elucidated. OBSERVATION: The case describes a 17-year-old transgender male treated with testosterone therapy who presented with an occlusive deep vein thrombosis of right axillary and subclavian veins. Testosterone level was 920 ng/dL at the time of the deep vein thrombosis, and he had no risk factors for VTE. A complete hypercoagulable workup was negative. CONCLUSIONS: The possibility of testosterone therapy as a risk factor for VTE may suggest the need to include this information during informed consent discussions. Long-term anticoagulation may be considered for those restarting testosterone therapy.

Discarded portions of bone marrow aspirates are a new resource for patient-derived mesenchymal stem and stromal cells.

Bone marrow-derived mesenchymal stem and stromal cells (BM-MSCs) protect malignant cells from chemotherapy and are important potential therapeutic targets. Isolating primary BM-MSCs for research traditionally requires the sacrifice of valuable cell populations from within the same sample. To avoid this, we report here a resource for isolating patient-derived BM-MSCs from the red blood cell layer of ficoll gradients of bone marrow aspirates, a resource that has until now been universally discarded. This resource yields BM-MSCs nearly identical to those obtained conventionally and includes cells with a more stem-cell like nature. Obtaining primary BM-MSCs in this way will likely expand opportunities to study this important cell population.

Interprofessional orientation for health professionals utilising simulated learning: Findings from a pilot study.

We describe a novel, interprofessional educational intervention pilot used to orient new health profession employees through the simulation laboratory. Health profession employees were recruited to engage in a simulation training session that focused on communication, collaboration, and healthcare roles and responsibilities. Learners (N = 11) were divided into two groups with representation from various health disciplines. Each group participated in a simulated patient scenario while the other group actively observed in another classroom. At the end of both sessions, the group reconvened for a debriefing session. Participants were given a survey before and after the training session, to evaluate the content, experience, and value to their practice. The pre- and post-evaluation survey analysis showed improvement in all objectives with a mean (SD) pre-evaluation score of 4.10 (0.40-1.01) and mean (SD) post-evaluation score of 4.73 (0.30-0.81). Results were favourable, and plans to expand this project are under way.

The development and validation of a psychological questionnaire for patients undergoing orthognathic treatment.

OBJECTIVES: To develop a questionnaire to assess the psychosocial aspects which orthognathic patients considered important regarding their dento-facial deformity. SETTING AND SAMPLE POPULATION: A multicentre, prospective, questionnaire development and validation study based in the UK. MATERIAL AND METHODS: Questionnaire development involved item (question) selection through literature review, consultation and feedback from a questionnaire development group and semi-structured interviews. A 'final' questionnaire was tested on a cross-sectional sample of 110 pre-operative and 74 post-operative orthognathic patients and a longitudinal sample of 23 orthognathic patients. Validity was tested using Rasch analysis. RESULTS: Reliability for the Hospital Anxiety and Depression Scale (HADS) section was unsatisfactory (ICC = 0.232-0.829, Cronbach alpha = 0.625-0.670), but for the well- being (ICC = 0.857, Cronbach alpha = 0.827-0.895) and expectations (ICC = 0.861, Cronbach alpha = 0.804-0.882) sections were satisfactory. The well-being section was the only section found to be valid for the pre-and post-operative samples. Responsiveness was satisfactory for the well-being scale (p = 0.001). CONCLUSIONS: A new condition-specific orthognathic questionnaire has been developed which has been shown to be reliable, valid and responsive for the well-being scale. The HADS, as tested by Rasch analysis, was found not to be valid for this orthognathic population.

Performance of arrhenotokous and thelytokous Thrips tabaci (Thysanoptera: Thripidae) on onion and cabbage and its implications on evolution and pest management.

Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), is an important pest on onion and cabbage. Two reproductive modes--arrhenotoky and thelytoky--are found in this species and co-occur in the field. We compared life table traits between arrhenotokous and thelytokous T. tabaci on cabbage and onion. Experiments were conducted in cages to determine which reproductive mode is more competitive. Additionally, host adaption of the arrhenotokous and thelytokous T. tabaci between onion and cabbage was investigated. On onion, arrhenotokous T. tabaci performed better than thelytokous T. tabaci, while on cabbage the opposite occurred. When comparing life table and demographic growth parameters (net reproductive rates R(o), mean generation time T, the intrinsic rate of natural increase r(m), finite rate of increase A, and population doubling time T(d)) on different host plants, we found that arrhenotokous T. tabaci performed better on onion than on cabbage, whereas thelytokous T. tabaci performed better on cabbage than on onion. Host-related performance differences in this species suggest that the divergence between two reproductive modes might be associated with host adaption. Pest management strategies for this global pest should recognize that the two reproductive modes can impact population dynamics on different crops.

Multi-state trials of Bt sweet corn varieties for control of the corn earworm (Lepidoptera: Noctuidae).

Field tests in 2010-2011 were performed in New York, Minnesota, Maryland, Ohio, and Georgia to compare Bt sweet corn lines expressing Cry1A.105 + Cry2Ab2 and Cry1Ab with their non-Bt isolines, with and without the use of foliar insecticides. The primary insect pest in all locations during the trial years was Heliocoverpa zea (Boddie), which is becoming the most serious insect pest of sweet corn in the United States. At harvest, the ears were measured for marketability according to fresh market and processing standards. For fresh market and processing, least squares regression showed significant effects of protein expression, state, and insecticide frequency. There was a significant effect of year for fresh market but not for processing. The model also showed significant effects of H. zea per ear by protein expression. Sweet corn containing two genes (Cry1A.105 + Cry2Ab2) and a single gene (Cry1Ab) provided high marketability, and both Bt varieties significantly outperformed the traditional non-Bt isolines in nearly all cases regardless of insecticide application frequency. For pest suppression of H. zea, plants expressing Bt proteins consistently performed better than non-Bt isoline plants, even those sprayed at conventional insecticide frequencies. Where comparisons in the same state were made between Cry1A.105 + Cry2Ab2 and Cry1Ab plants for fresh market, the product expressing Cry1A.105 + Cry2Ab2 provided better protection and resulted in less variability in control. Overall, these results indicate Cry1A.105 + Cry2Ab2 and Cry1Ab plants are suitable for fresh market and processing corn production across a diversity of growing regions and years. Our results demonstrate that Bt sweet corn has the potential to significantly reduce the use of conventional insecticides against lepidopteran pests and, in turn, reduce occupational and environmental risks that arise from intensive insecticide use.

An evaluation of intravenous medication preparation times before and after implementation of first-party digital image capture functionality.

PURPOSE: The intravenous (IV) medication compounding workflow has long been associated with preventable medication errors. This has led to the development of technologies designed to enhance the safety of IV compounding workflows. Digital image capture is a component of this technology about which there is relatively limited published literature. This study evaluates image capture implemented within an electronic health record's existing first-party IV workflow solution. METHODS: A retrospective case-control study was conducted to measure IV preparation times before and after digital imaging implementation. Preparations during 3 periods (preimplementation, ≤1 month post implementation, and >1 month post implementation) were matched for 5 variables. A less stringent analysis with matching for 2 variables, as well as an unmatched analysis, were performed post hoc. An employee survey assessed satisfaction with the digital imaging workflow, and revised orders were reviewed to identify new problems introduced by image capture. RESULTS: A total of 134,969 IV dispenses were available for analysis. Median preparation time in the preimplementation and >1 month post implementation cohorts was unchanged in the 5-variable matched analysis (6.87 minutes vs 6.58 minutes, P = 0.14) and increased in the 2-variable matched analysis (6.98 minutes vs 7.35 minutes, P < 0.001) and unmatched analysis (6.55 minutes vs 8.02 minutes, P < 0.001). A large majority of survey respondents (92%) felt that image capture improved patient safety. Of the 105 postimplementation preparations identified as requiring revisions by the checking pharmacist, 24 (22.9%) required revisions directly related to camera functionality. CONCLUSION: Implementation of digital image capture likely increased preparation times. Most IV room staff felt that image capture increased preparation times and were satisfied with how the technology improved patient safety. Image capture introduced camera-specific issues that led to preparations requiring revisions.

Nonorganic (Behavioral) Signs and Their Association With Epidural Corticosteroid Injection Treatment Outcomes and Psychiatric Comorbidity in Cervical Radiculopathy: A Multicenter Study.

OBJECTIVE: To determine the association between cervical nonorganic pain signs and epidural corticosteroid injection outcomes and coexisting pain and psychiatric conditions. PATIENTS AND METHODS: Seventy-eight patients with cervical radiculopathy who received epidural corticosteroid injection were observed to determine the effects that nonorganic signs have on treatment outcome. A positive outcome was a decrease of 2 or more points in average arm pain, coupled with a score of 5 on a 7-point Patient Global Impression of Change scale 4 weeks after treatment. Nine tests in 5 categories (abnormal tenderness, regional disturbances deviating from normal anatomy, overreaction, discrepancies in examination findings with distraction, and pain during sham stimulation) were modified from previous studies and standardized. Other variables examined for their association with nonorganic signs and outcomes included disease burden, psychopathology, coexisting pain conditions, and somatization. RESULTS: Of the 78 patients, 29% (n=23) had no nonorganic signs, 21% (n=16) had signs in 1 category, 10% (n=8) had signs in 2 categories, 21% (n=16) had signs in 3 categories, 10% (n=8) had signs in 4 categories, and 9% (n=7) had signs in 5 categories. The most common nonorganic sign was superficial tenderness (44%; n=34). Mean number of positive nonorganic categories was higher in individuals with negative treatment outcomes (2.5±1.8; 95% CI, 2.0 to 3.1) compared with those with positive outcomes (1.1±1.3; 95% CI, 0.7 to 1.5; P=.0002). Negative treatment outcomes were most strongly associated with regional disturbances and overreaction. Positive associations were noted between nonorganic signs and multiple pain (P=.011) and multiple psychiatric (P=.028) conditions. CONCLUSION: Cervical nonorganic signs correlate with treatment outcome, pain, and psychiatric comorbidities. Screening for these signs and psychiatric symptoms may improve treatment outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04320836.

Assessment of static progressive stretch for the treatment of shoulder stiffness: a prospective case series.

INTRODUCTION: The purpose of this study was to evaluate the use of a patient-directed static progressive stretch orthosis for the treatment of shoulder stiffness. METHODS: Twenty-three patients who had limitations in range of motion of the shoulder and who had failed conventional physical therapy methods were studied. This cohort included 15 women and 8 men with a mean age of 53 years. Treatment comprised one to three 30- to 60-minute sessions per day with a patient-controlled orthosis utilizing static progressive stretch. The patients adjusted the degree of stretch at 5-minute intervals as tolerated. Compliance, range of motion, patient satisfaction, and complications were assessed, and a two-way repeated measure ANOVA was performed to assess the effects of age or gender. RESULTS: After a mean treatment duration of 10 weeks (range, 4 to 19 weeks), the patients gained a mean of 22° (range, -47 to 57°) of external rotation, 18° (range, -19 to 55°) of internal rotation, 46° (range, 3 to 97°) of abduction, and 23° (range, 3 to 40°) of forward flexion. In total, 22 of 23 patients (96%) experienced increases in range of motion that were maintained at 1 year following treatment. Statistically significant increases in range of motion and clinical function scores were noted; age and gender did not appear to influence the outcomes. DISCUSSION: This device compared favorably to other treatment methods for shoulder stiffness. An orthosis utilizing static progressive stretch was a useful adjunct for the treatment of shoulder stiffness refractory to conventional therapy.

The Utility of Dynamic Movement Orthoses in the Management of Complex Regional Pain Syndrome-A Case Series.

Complex regional pain syndrome (CRPS) is a relatively rare, but debilitating condition that may occur after limb or peripheral nerve trauma. Typical symptoms of CRPS include swelling, allodynia, hyperalgesia, and skin temperature changes. Although a variety of pharmacological and non-pharmacological approaches are commonly used in caring for individuals with CRPS, they are frequently ineffective and often associated with side effects and/or additional risks. Previously, elastomeric orthotic garments have been shown to decrease neuropathic pain, reduce edema, and increase proprioception, but no previous reports have described their use in treating CRPS. Accordingly, this case series describes our experiences using a Lycra-based, custom-fabricated Dynamic Movement Orthosis (DMO) as a novel treatment to reduce the symptoms of CRPS and promote function. Four patients were included in this case series, all of whom had very different causes for their CRPS, including a combat-related gunshot injury resulting in multiple foot fractures with a partial nerve injury, a post-metatarsophalangeal fusion, an L5 radiculopathy, and a case of post-lower leg fasciotomies. These four patients all reported subjective improvement in their pain, function, and exercise tolerance in association with their DMO use. All patients demonstrated reduced use of analgesic medications. The pre- and post-DMO lower extremity functional scale showed clinically significant improvement in the two patients for which it was obtained.

Pathological response after chemoradiation for T3 rectal cancer.

OBJECTIVE: The aim of this study was to investigate the effect of preoperative chemoradiotherapy (CRT) on nodal disease in locally advanced rectal adenocarcinoma. METHOD: Thirty-two patients staged uT3N0 and 27 patients staged uT3N1 rectal adenocarcinoma who underwent pre-CRT staging using endoscopic ultrasound or rectal protocol CT were included. The median radiation dose was 50.4 Gy (range: 45-50.4 Gy) at 1.8 Gy per fraction and all patients received concurrent 5-FU or capecitabine-based chemotherapy. Low anterior resection or abdomino-perineal resection occurred at a median of 46 days (range: 27-112 days) after CRT. RESULTS: Eleven of 32 uT3N0 patients (34.4%) and 13 of 26 uT3N1 patients (50.0%) had ypN+ (P = 0.29). For patients with uT3N0, 10 of 20 (50.0%) with ypT2-3 and 1 of 12 (8.3%) with ypT0-1 were ypN+ (P = 0.02). For patients with uT3N1, 12 of 20 (60.0%) with ypT2-3 and 1 of 6 (16.7%) with ypT0-1 were ypN+ (P = 0.16). Overall, the ypN+ rate was 11.1% in the ypT0-yT1 group compared with 55.0% in the ypT2-yT3 group (P = 003). Among patients with uT3N0 disease, the ypN+ rate in patients who had surgery > 46 days vs 46 days vs 46 days vs

Assessing the susceptibility of cruciferous Lepidoptera to Cry1Ba2 and Cry1Ca4 for future transgenic cruciferous vegetables.

Advances in transgenic plants expressing Bacillus thuringiensis (Bt) insecticidal gene(s) offer a promising alternative to traditional insecticides for control of lepidopteran pests on important cruciferous vegetable crops such as cabbage and cauliflower. A public-private partnership, the Collaboration on Insect Management for Brassicas in Asia and Africa (CIMBAA), was formed in 2005 with the goal of developing dual-gene Bt cauliflower and cabbage, initially for India, to replace the use of broad spectrum, traditional insecticides. As a first step in this effort, the major lepidopteran pests of cruciferous vegetable crops [Plutella xylostella (L.), Pieris rapae (L.), Pieris brassicae (L.), Crocidolomia binotalis (L.), Hellula undalis (F.), Diacrisia obliqua Walker, Spodoptera litura F., and Helicoverpa armigera (Hübner)] were collected over a large geographic area (India, Indonesia, Taiwan, China, Australia, and the United States) and tested against purified Cry1Ba2 and Cry1Ca4 toxins, the toxins proposed to be expressed in the CIMBAA plants. Our results demonstrate that Cry1Ba2 and Cry1Ca4 were effective against the primary target of the CIMBAA plants, P. xylostella, regardless of geographic location, and had LC50 values <1.3 ppm. Furthermore, one or both toxins were effective against the other major pest Lepidoptera, except for S. litura or H. armigera which were less susceptible. No cross-resistance has been found between Cry1Ba2 and Cry1Ca4, suggesting cry1Ba2+cry1Ca4 cauliflower and cabbage could be an effective and sustainable tool to control, P. xylostella, the key lepidopteran pest on cruciferous vegetable crops, as well as most other Lepidoptera. As the CIMBAA plants are being developed, further tests are needed to determine whether they will express these proteins at sufficient levels to control all the Lepidoptera. Sustainable use of the dual-gene plants also is discussed.

3- Instead of 4-helix formation in a de novo designed protein in solution revealed by small-angle X-ray scattering.

De novo design and chemical synthesis of proteins and their mimics are central approaches for understanding protein folding and accessing proteins with novel functions. We have previously described carbohydrates as templates for the assembly of artificial proteins, so-called carboproteins. Here, we describe the preparation and structural studies of three alpha-helical bundle carboproteins, which were assembled from three different carbohydrate templates and one amphiphilic hexadecapeptide sequence. This heptad repeat peptide sequence has been reported to lead to 4-alpha-helix formation. The low resolution solution structures of the three carboproteins were analyzed by means of small-angle X-ray scattering (SAXS) and synchrotron radiation circular dichroism (SRCD). The ab initio SAXS data analysis revealed that all three carboproteins adopted an unexpected 3+1-helix folding topology in solution, while the free peptide formed a 3-helix bundle. This finding is consistent with the calculated alpha-helicities based on the SRCD data, which are 72 and 68 % for two of the carboproteins. The choice of template did not affect the overall folding topology (that is for the 3+1 helix bundle) the template did have a noticeable impact on the solution structure. This was particularly evident when comparing 4-helix carboprotein monomers with the 2x2-helix carboprotein dimer as the latter adopted a more compact conformation. Furthermore, the clear conformational differences observed between the two 4-helix (3+1) carboproteins based on D-altropyranoside and D-galactopyranoside support the notion that folding is affected by the template, and subtle variations in template distance-geometry design may be exploited to control the solution fold. In addition, the SRCD data show that template assembly significantly increases thermostability.

Static progressive stretch for the treatment of knee stiffness.

Persistent knee stiffness is common after knee arthroplasties, cruciate ligament repairs, and trauma. Static progressive stretch protocols have shown success in treating contractures of the elbow, ankle, and knee in case reports and small case series. This study evaluated static progressive stretch as a treatment method for patients who had refractory knee stiffness, and compared the outcomes to published results of other therapeutic modalities. Forty-one patients who had knee stiffness and who had not improved with conventional physical therapy modalities were treated with a patient-directed orthosis that utilized the principles of static progressive stretch. After a mean of 9 weeks of use (range, 3 to 27 weeks), the total arc of motion increased by a mean of 33 degrees (range, 0 to 85 degrees ). Forty of 41 patients had increased motion at a mean final follow-up time of 1 year (range, 6 months to 2 years), and 93% were satisfied with the results. The outcomes were comparable to other nonoperative treatments reported in the literature, but the results in the present study occurred in a shorter mean treatment time. An orthosis that utilizes the principles of static progressive stretch may be a successful treatment for improving the range of motion and satisfaction of patients who have knee contractures.

Advances in control of onion thrips (Thysanoptera: Thripidae) in cabbage.

Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), feeding injury results in discoloration and a rough texture on cabbage, Brassica oleracea capitata (L.), leaves, and damage may occur deep inside the head. It has become a key pest of cabbage in the United States and many other countries. Previous studies have indicated poor control using insecticides. The present study identified imidacloprid drenches and sprays of acetamiprid, dimethoate, spinosad, and imidacloprid as insecticides that performed better than the industry standard, lambda-cyhalothrin. However, additional tests with foliar sprays of dimethoate and acetamiprid indicated there was not an ideal crop stage (precupping, cupping, or postcupping) at which either insecticide could be applied for reliable control of T. tabaci, possibly because of multiple flights of thrips into the crop or the asynchrony of flights and susceptible crop stages. In tests in a commercial field, a soil drench of imidacloprid 4 wk after transplanting reduced the number of damaged leaves in the head by 32%, whereas five sprays of acetamiprid reduced damage by 51%. Combining both insecticide regimes reduced damage by 85%, but resulted in a very costly management program. Cabbage varieties varied considerably in susceptibility with some having negligible thrips injury, regardless of being treated with an insecticide. Planting date affected susceptibility of cabbage to some degree, but not as much as other tactics. Overall, these studies indicate that increased emphasis should be placed on breeding cabbages to be resistant to T. tabaci as the foundation for its management.

Impact of straw mulch on populations of onion thrips (Thysanoptera: Thripidae) in onion.

Development of insecticide resistance in onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), populations in onion (Allium spp.) fields and the incidence of the T. tabaci transmitted Iris yellow spot virus have stimulated interest in evaluating alternative management tactics. Effects of straw mulch applied in commercial onion fields in muck areas of western New York were assessed in 2006 and 2007 as a possible onion thrips management strategy. In trials in which no insecticides were applied for thrips control, straw mulch-treated plots supported significantly lower T. tabaci populations compared with control plots. In both years, the action thresholds of one or three larvae per leaf were reached in straw mulch treatments between 7 and 14 d later than in the control. Ground predatory fauna, as evaluated by pitfall trapping, was not increased by straw mulch in 2006; however, populations of the common predatory thrips Aeolothrips fasciatus (L.) (Thysanoptera: Aeolothripidae) were significantly lower in straw mulch plots in both years. Interference of straw mulch in the pupation and emergence of T. tabaci was investigated in the lab and their emergence was reduced by 54% compared with bare soil. In the field the overall yield of onions was not affected by the straw mulch treatment; however, the presence of jumbo grade onions (>77 mm) was increased in 2006, but not in 2007. These results indicate that populations of T. tabaci adults and larvae can be significantly reduced by the use of straw mulch without compromising overall onion yield. The use of this cultural practice in an onion integrated pest management program seems promising.

A preliminary evaluation of pre-treatment hypodontia patients using the Dental Aesthetic Index: how does it compare with other commonly used indices?

There is currently no specific occlusal index related to hypodontia and there is a paucity of published literature on this subject. The aim of this study was to determine the relationship, if any, between the Peer Assessment Rating (PAR) Index, the Index of Complexity, Outcome and Need (ICON), and the Dental Aesthetic Index (DAI) score and the severity of hypodontia. All new patients attending the Newcastle Dental Hospital hypodontia clinic between February 2002 and March 2003 were included in the study. Of the 60 patients, two were excluded as the models were unavailable and one because they were predominantly in the primary dentition, making scoring impractical. The patient casts were scored with respect to PAR, ICON, and DAI. The mean patient age at presentation was 12 years, with a standard deviation of 1.89 and a range of 9-16 years, and a female to male ratio of 1.1:1. A significant positive correlation, using Kendall tau b, was found between the number of missing teeth, excluding third molars, and the DAI score (tau = 0.215, P = 0.027). There was no significant positive correlation between PAR (tau = -0.186, P = 0.056) and ICON (tau = 0.017, P = 0.861) score and the number of missing teeth. The results of this investigation indicate that further research is required in order to assess if the DAI could be used to determine whether or not to refer hypodontia patients for specialist advice.

Bt Eggplant Project in Bangladesh: History, Present Status, and Future Direction.

The purpose of this article is to provide information on the history, accomplishments, and future direction of the Bt brinjal (eggplant) program in Bangladesh, formerly under the Agricultural Biotechnology Support Project II, now the South Asia Eggplant Improvement Partnership (SAEIP). The India-based Maharashtra Hybrid Seed Company (Mahyco) developed an eggplant expressing Cry1Ac (EE-1) for control of the eggplant fruit and shoot borer (EFSB). In a partnership among Mahyco, USAID, Sathguru Management Consultants and Cornell University EE-1 was provided to the Bangladesh Agricultural Research Institute (BARI) who bred it into local varieties. After regulatory approval, four varieties were distributed to 20 farmers who harvested Bt brinjal in 2014. Adoption in subsequent years has increased rapidly so that, in 2018, 27,012 farmers used this technology. This article provides background information on the process leading up to current adoption levels, the level of control of EFSB achieved and the economic benefits of Bt brinjal. Efforts on stewardship, farmer training and communication are discussed. In order to ensure the long-term future of the partnership, we discuss the need to enhance involvement of the private sector in the production and stewardship of Bt eggplant. Bt brinjal is the first genetically engineered crop to be commercially released in Bangladesh, and other GE crops are in the pipeline. Hence, success of the Bt brinjal partnership is likely to affect the future of other GE crops in Bangladesh, as well as other parts of the world where biotechnology is needed for food security and environmental safety.

Field tests on managing resistance to Bt-engineered plants.

Several important crops have been engineered to express toxins of Bacillus thuringiensis (Bt) for insect control. In 1999, US farmers planted nearly 8 million hectares (nearly 20 million acres) of transgenic Bt crops approved by the EPA. Bt-transgenic plants can greatly reduce the use of broader spectrum insecticides, but insect resistance may hinder this technology. Present resistance management strategies rely on a "refuge" composed of non-Bt plants to conserve susceptible alleles. We have used Bt-transgenic broccoli plants and the diamondback moth as a model system to examine resistance management strategies. The higher number of larvae on refuge plants in our field tests indicate that a "separate refuge" will be more effective at conserving susceptible larvae than a "mixed refuge" and would thereby reduce the number of homozygous resistant (RR) offspring. Our field tests also examined the strategy of spraying the refuge to prevent economic loss to the crop while maintaining susceptible alleles in the population. Results indicate that great care must be taken to ensure that refuges, particularly those sprayed with efficacious insecticides, produce adequate numbers of susceptible alleles. Each insect/Bt crop system may have unique management requirements because of the biology of the insect, but our studies validate the need for a refuge. As we learn more about how to refine our present resistance management strategies, it is important to also develop the next generation of technology and implementation strategies.

Overwintering locations and hosts for onion thrips (Thysanoptera: Thripidae) in the onion cropping ecosystem in New York.

Identifying locations where onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), overwinter and subsequently disperse is important for designing control strategies. In upstate New York from 2003 through 2006, potential overwintering sites in the commercial onion, Allium cepa L., cropping system were investigated early in the spring before onion seedling emergence and again late in the season after onions were harvested. Onion thrips adults were sampled directly from the soil and indirectly from the soil by using emergence cages. Sampling locations included onion field interiors and edges and areas outside of these fields, including woods. Host material sampled included onion culls; volunteer onions, which sprout from cull onions left behind after harvest; and weeds. Onion thrips adults were found in all sections of onion fields and in locations outside of onion fields, with the fewest emerging from woods. Emergence began in early May and extended into June. Peak emergence occurred during the last half of May, at which time 50-75% of the population had emerged. Adults colonized volunteer onions as early as late March and as late as mid-November. No adults were found overwintering in onion cull piles. Adults also colonized several weed species, especially pigweed, Amaranthus hybridis L., and lambsquarters, Chenopodium album L., late in the fall. Our results indicate that onion thrips adults overwinter in the soil within and near onion fields and that they probably colonize volunteer onion plants before subsequent generations infest the onion crop in the spring. Volunteer onions and weeds also provide onion thrips with a host after onions are harvested. Consequently, onion thrips management strategies should include tactics that reduce volunteer onion and weed abundance.