Maximum Label Research Articles

Radioiodinated paroxetine, a novel potential radiopharmaceutical for lung perfusion scan

Paroxetine (a selective serotonin reuptake inhibitor) was successfully labeled with 125I via direct electrophilic substitution reaction at ambient temperature. The reaction parameters studied were paroxetine amount, CAT amount, pH of the reaction mixture, reaction temperature, reaction time and in vitro stability of 125I-paroxetine. 125I-paroxetine was obtained with a maximum labeling yield of 94 ± 0.23% and in vitro stability up to 24 h. Biodistribution studies showed that maximum in vivo uptake of 125I-paroxetine in lungs was 27.89 ± 1.03% injected activity/g tissue at 15 min post-injection and retention in lungs remained high up to 1 h, whereas the clearance from mice appeared to proceed mainly via the hepatobiliary pathway. 125I-paroxetine is not a blood product and so it is more safe than the currently available 99mTc-macroaggregated albumin (99mTc-MAA), and its lung uptake is higher than that of the recently discovered 99mTc(CO)5I and 99mTc-DHPM. As a conclusion, radioiodinated paroxetine could be used as a novel radiopharmaceutical for lung perfusion scan safer than the currently available 99mTc-MAA and more potential than the recently discovered 99mTc(CO)5I and 99mTc-DHPM.

Longevity and Efficacy of Bifenthrin Treatment on Desert-Pattern US Military Camouflage Netting Against Mosquitoes in a Hot-Arid Environment

The current Department of Defense pest management system does not provide adequate protection from arthropod disease vectors to personnel deployed in support of US military operations. We hypothesized that military camouflage netting, ubiquitous around living and working areas in current US military operations in Africa and the Middle East, treated with a residual pesticide such as bifenthrin may reduce the presence of biting insects and improve the military pest management system. In this study, we examined the longevity and efficacy of bifenthrin applied to camouflage netting material at the maximum label rate of 0.03 liter formulation (7.9% AI) per 92.9 m2 against field populations of mosquitoes in southern California in a hot-arid environment similar to regions of Iraq, Afghanistan, and the Horn of Africa. We showed that bifenthrin treatment of camouflage netting was effective at reducing mosquito populations, predominantly Psorophora columbiae and Aedes vexans, by an average of up to 46% for 56 days, and could cause as much as 40% mortality in Culex quinquefasciatus in laboratory bioassays for nearly 2 months postapplication. These population reductions could translate to commensurate reductions in risk of exposure to mosquito-borne pathogens, and could potentially be effective against sand flies and filth flies.

Efficacy of Several Commercially Formulated Essential Oils Against Caged Female Aedes albopictus and Culex quinquefasciatus when Operationally Applied via an Automatic-Timed Insecticide Application System

The effectiveness of several commercially available products containing plant essential oils against caged female Aedes albopictus and Culex quinquefasciatus was studied. Products operationally applied via an automatic-timed insecticide application system (MistAway) at maximum label rates were EcoExempt MC (9.0 ml/liter, rosemary oil [18% AI], cinnamon oil [2% AI], lemongrass oil [2% AI], plus 78% "other ingredients" in wintergreen oil). Misting System Concentrate (4 ml/liter, oil of Juniperus virginiana [85% AI]), Mosquito Barrier (31.1 ml/liter, garlic oil [99.3% AI], and citric acid [0.5% AI]), and No-See-Um Organic Repellent (99.5 ml/liter, lemongrass [4% AI], citronella [3% AI], castor oil [3% AI], sodium laurate [3%], and garlic oil [1% AI] in an 86% [AI] mixture of wintergreen oil, lecithin, and water). All products were compared with a commercial formulation of synergized pyrethrins, Riptide (9.0 ml/liter, pyrethrins [5% AI], piperonyl butoxide [25% AI]), as a standard. Mortality was the greatest for Riptide to both mosquito species with effectiveness influenced by distance from the nozzle (ranging from > 80% at 3 m to > 10% at 20 m). The essential oil products resulted in < 10% mortality for each species regardless of application exposure distance with the exception of EcoExempt, which gave approximately 13% mortality of caged female Ae. albopictus 6 m from the nozzles.

Alternative Organic Fungicides for Apple Scab Management and Their Non-target Effects

A major challenge in organic apple production in humid production regions is the available fungicide options for apple scab [Venturia inaequalis (Cooke) Wint.] management. The standard sulfur/lime sulfur fungicide program can be injurious to the applicator, the apple ecosystem, and the apple tree itself. The objectives of this study were to compare the efficacy of three potential alternative fungicides [potassium bicarbonate (PB), neem oil (NO), and Bacillus subtilis (Bs)] with a standard organic sulfur/lime sulfur (SLS) fungicide program and a non-treated control (NTC) for management of apple scab and to evaluate potential non-target impacts on pest and beneficial arthropod populations. The five treatments were applied to ‘Empire’ trees arranged in a completely randomized design with five single-tree replications at the University of Vermont Horticultural Research Center in South Burlington, VT. Fungicides were applied with a handgun to drip using maximum label rates. Applications began on 26 Apr. 2007 and 23 Apr. 2008 and continued on approximately a weekly schedule through the end of June and then every 2 weeks through 23 July 2007 and 17 July 2008, respectively. The standard SLS treatment resulted in the best scab control in both years. The NO treatment reduced foliar and fruit scab compared with the NTC and the other alternatives at the end of the 2008 growing season and had insecticidal activity. However, both the SLS and NO treatments had disadvantages, including phytotoxic burning on the fruit and/or significantly more russeting on the fruit at harvest. In each year of the study, one or more of the alternative treatments, particularly Bs, resulted in higher insect damage than the non-fungicide-treated control. This research showed that PB, Bs, and NO do not offer advantages over the standard SLS fungicide program in organic apple production and in some cases offer distinct disadvantages in terms of non-target impacts. Chemical names used: potassium bicarbonate (Armicarb “O”), Bacillus subtilis (Serenade MAX), neem oil (Trilogy), sulfur (Microthiol Sulfur)/lime sulfur (Miller Lime Sulfur)

Novel radioiodinated sibutramine and fluoxetine as models for brain imaging

Brain imaging is a process which allows scientists and physicians to view and monitor the areas of the brain which allow diagnosis and following up different abnormalities in the brain. The aim of this study was to develop potential radiopharmaceuticals for the non-invasive brain imaging. Sibutramine and fluoxetine (two drugs that have the ability to cross blood–brain barrier) were successfully labeled with 125I via direct electrophilic substitution reaction at ambient temperature. The reaction parameters studied were substrate concentration, oxidizing agent concentration, pH of the reaction mixture, reaction temperature, reaction time and in vitro stability of the iodocompounds. The iodocompounds gave maximum labeling yield of 92 ± 2.77 and 93 ± 2.1%, respectively, and maintained stability throughout working period (24 h). Biodistribution studies showed that maximum in vivo uptake of the iodocompounds in the brain was 5.7 ± 0.19 and 6.14 ± 0.26% injected activity/g tissue organ, respectively, at 15 and 5 min post-injection, whereas the clearance from the mice appeared to proceed via the hepatobiliary pathway. Brain uptake of 125I-sibutramine and 125I-fluoxetine is higher than that of 99mTc-ECD and 99mTc-HMPAO (currently used radiopharmaceuticals for brain imaging) and so radioiodinated sibutramine and fluoxetine could be used instead of 99mTc-ECD and 99mTc-HMPAO for brain SPECT.

Distance three labelings of trees

An L(2,1,1)-labeling of a graph G assigns nonnegative integers to the vertices of G in such a way that labels of adjacent vertices differ by at least two, while vertices that are at distance at most three are assigned different labels. The maximum label used is called the span of the labeling, and the aim is to minimize this value. We show that the minimum span of an L(2,1,1)-labeling of a tree can be bounded by a lower and an upper bound with difference one. Moreover, we show that deciding whether the minimum span attains the lower bound is an NP-complete problem. This answers a known open problem, which was recently posed by King, Ras, and Zhou as well. We extend some of our results to general graphs and/or to more general distance constraints on the labeling.

Control of Mosquitoes in Catch Basins in Connecticut With Bacillus thuringiensis israelensis, Bacillus sphaericus, and Spinosad

Catch basins are a major source of Culex pipiens pipiens, Cx. restuans, and Aedes japonicus in northeastern USA. VectoBac CG (Bacillus thuringiensis israelensis [Bti]), VectoLex CG (Bacillus sphaericus [Bs]), and VectoBac 12AS (Bti), each applied at maximum label rate of 1.8 g, 1.8 g, and 0.193 ml per catch basin, respectively, significantly reduced the numbers of larvae for 1 wk. The dosages on the labels for treatment of mosquito larvae in catch basins, where mosquito breeding is continuous, are not adequate for providing long-term control in the northeastern USA without the need for frequent retreatment. When applied at 3 times the maximum label rate, VectoLex CG, VectoBac 12AS, and VectoBac CG significantly reduced the numbers of larvae for 5, 4, and 2 wk, respectively. A single application of VectoMax WSP (Bti + Bs) (1 pouch containing 10 g) per catch basin significantly reduced the numbers of 3rd and 4th instars and healthy pupae in catch basins in 2008, but numbers of 3rd and 4th instars in treated catch basins at 21 days after treatment had increased to 40% of the numbers in untreated catch basins. A 2nd treatment of 1 pouch per catch basin reduced the numbers of 3rd and 4th instars and healthy pupae to near zero for the next 4 wk, into the middle of September 2008. In 2009, VectoMax applied as 1 pouch per catch basin on July 1 and again on August 18 significantly reduced the numbers of healthy pupae throughout the summer until the end of September. A 2nd application of VectoMax to catch basins is likely needed during summer, when rainfall averages 13.7 in. (approximately 34.25 cm) during June through September, to keep the numbers of Culex and Ae. japonicus significantly reduced to lower risk of human exposure to West Nile virus. The application of 1 Natular XRT tablet, each weighing approximately 40.5 g (6.25% spinosad), to individual catch basins in 2009 significantly reduced the total numbers of larvae for 5 wk.

Mechanisms of Entry of Vaccinia Virus into Cells Studied by Photosensitized Labeling

Vaccinia virus is a prototype member of the poxviruses that has a complex genome consisting of more than 200 genes. Along with this comes a complex assembly process giving rise to various forms of the virus whose topology needs to be further studied. To study fusion of intact virions with cells we have developed methodologies based on photosensitized activation by fluorescent lipid analogs of a hydrophobic probe, [125I]5-iodonaphthyl-1-azide ([125I]INA), that rapidly partitions into the membrane bilayer of cells. The photosensitized labeling methodology involves measurement of incorporation of [125I]INA into the viral membrane-resident protein(s) as a result of virus-cell fusion. We can therefore assess the extent of membrane fusion at different times of interaction between the virus and its target cell and determine the sensitivity of this process to various compounds. We monitored vaccinia fusion with HeLa cells by assessing the incorporation of [125I]INA into a vaccinia membrane protein D8L. Maximum labeling was observed upon 30 minutes incubation at physiological pH. This phenomenon was enhanced by the exposure of the prebound virus to a pH5 pulse. The measurements specificity was confirmed by the inability of the heat inactivated virus and entry-deficient mutants to induce D8L labeling. While supporting the hypothesis of a membrane fusion phenomenon, those observations also support a route of entry of the virus through internalization by endocytosis. However, comparison with influenza virus for endosomal entry indicates striking differences in their sensitivity to inhibitors of endosomal processes. To further assess endosomal entry we used a dynamin inhibitor, dynasore, which blocks vaccinia entry as measured using a gene reporter assay. Interestingly dynasore also inhibited the labeling of cells with fluorescent lipids. The multiple effects of dynasore are being further studied. Funded in part by NCI Contract HHSN26120080001E.

Laboratory assays of select candidate insecticides for control of Dendroctonus ponderosae

The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae), is the most destructive bark beetle in western North America. Dendroctonus ponderosae can be prevented from successfully colonizing and killing individual trees by ground-based sprays of insecticides applied directly to the tree bole. However, the future availability of several active ingredients, including carbaryl which is most commonly used in the western United States, is uncertain. Two novel insecticides, cyantraniliprole [Cyazypyr(™)-OD (oil dispersion) and Cyazypyr(™)-SC (suspension concentrate)] and chlorantraniliprole (Rynaxypyr(®)), and carbaryl were assayed in both filter paper and topical assays. Compared with 20,000 mg L(-1) carbaryl (i.e. the maximum label rate for solutions applied to conifers for protection from bark beetle attack in the western United States), cyantraniliprole OD caused similar rates of mortality in D. ponderosae adults at 400-fold weaker concentrations in both bioassays, while cyantraniliprole SC caused similar rates of mortality at 40-fold weaker concentrations. Probit analyses confirmed that D. ponderosae is most sensitive to cyantraniliprole OD, while chlorantraniliprole was effective at concentrations similar to carbaryl. These results suggest that lower concentrations of carbaryl have merit for field testing than have been previously considered. While cyantraniliprole and chlorantraniliprole have similar modes of action, cyantraniliprole OD appears to have greater promise for protecting individual trees from mortality attributed to D. ponderosae attack and should be evaluated in field studies.

Studies on 177Lu-labeled methylene diphosphonate as potential bone-seeking radiopharmaceutical for bone pain palliation

(99m)Tc-MDP (technetium-99(m)-labeled methylene diphosphonate) has been widely used as a radiopharmaceutical for bone scintigraphy in cases of metastatic bone disease. (177)Lu is presently considered as an excellent radionuclide for developing bone pain palliation agents. No study on preparing a complex of (177)Lu with MDP has been reported yet. Based on these facts, it was hypothesized that a bone-seeking (177)Lu-MDP (lutetium-177-labeled MDP) radiopharmaceutical could be developed as an agent for palliative radiotherapy of bone pain due to skeletal metastases. Biodistribution studies after intravenous injection of (177)Lu-MDP complex in rats may yield important information to assess its potential for clinical use as a bone pain palliation agent for the treatment of bone metastases. (177)Lu was produced by irradiating natural Lu(2)O(3) (10 mg) target at a thermal flux ∼ 8.0 × 10(13) n/cm(2) per second for 12 h in the swimming pool-type reactor.(177)Lu was labeled with MDP by adding nearly 37 MBq (1.0 mCi) of (177)LuCl(3) to a vial containing 10 mg MDP. The radiochemical purity and labeling efficiencies were determined by thin layer chromatography. Labeling of (177)Lu with MDP was optimized, and one sample was subjected to high-performance liquid chromatography (HPLC) analysis. Twelve Sprague-Dawley rats were injected with 18.5 MBq (0.5 mCi). (177)Lu-MDP in a volume of 0.1 ml was injected intravenously and then sacrificed at 2 min, 1 h, 2 h and 22 h (three rats at each time point) after injection. Samples of various organs were separated, weighed and measured for radioactivity and expressed as percent uptake of injected dose per gram. Bioevaluation studies with rats under gamma-camera were also performed to verify the results. The quality control using thin layer chromatography has shown >99% radiochemical purity of (177)Lu-MDP complex. Chromatography with Whatman 3MM paper showed maximum labeling at pH = 6, incubation time = 30 min, and ligand/metal ratio = 60:1. HPLC analysis showed 1.35 ± 0.05 min retention time of (177)Lu-MDP complex. No decrease in labeling was observed at higher temperatures, and the stability of the complex was found adequate. Biodistribution studies of (177)Lu-MDP revealed high skeletal uptake, i.e., 31.29 ± 1.27% of the injected dose at 22 h post injection. Gamma-camera images of (177)Lu-MDP in Sprague-Dawley rats also showed high skeletal uptake and verified the results. The study demonstrated that MDP could be labeled with (177)Lu with high radiochemical yields (>99%). The in vitro stability of the complex was found adequate. Biodistribution studies in Sprague-Dawley rats indicated selective bone accumulation, relatively low uptake in soft tissue (except liver) and higher skeletal uptake, suggesting that it may be useful as a bone pain palliation agent for the treatment of bone metastases.

Maximum gap labelings of graphs

Given a graph, we define a base set to be a set of integers of size equal to the number of vertices in the graph. Given a graph and a base set, a labeling of the graph from the base set is an assignment of distinct integers from the base set to the vertices of the graph. The gap of an edge in a labeled graph is the absolute value of the difference between the labels of its endpoints. The gap of a labeled graph is the sum of the gaps of its edges. The maximum gap graph labeling problem takes as input a graph and a base set and maximizes the gap of the graph over all possible labelings from the base set. We show that this problem is NP-complete even when the base set is restricted to consecutive integers. We also show that this restricted case has polynomial time approximations that achieve a factor of 2/3 for trees, of 1/2 for bipartite graphs, and of 1/4 for general graphs, with a deterministic algorithm, while an expected factor of 1/3 for general graphs is achieved with a randomized algorithm. The case of general base sets is approximated within an expected factor of 1/16 for general graphs with a randomized polynomial time algorithm. We finally give a polynomial time algorithm that solves the maximum gap graph labeling problem for a graph that has bounded degree and bounded treewidth. The maximum graph labeling problem shows connections with the graceful tree conjecture.

The effects of pre- and post-emergent herbicides on non-target native plant species of the longleaf pine ecosystem

Native grasses and forbs are an important component of the longleaf pine (Pinus palustris Mill.) ecosystem; however, information about re-establishment of these species in a restoration context has become available only recently. Understanding the effects of herbicides on non-target native plants can advance the use of herbicides as an effective restoration tool in the control of competing vegetation and in maintenance of seed production fields. The objectives of this study were to determine the effects of several commonly used herbicides on non-target species of grasses, legumes, and composites native to the longleaf pine ecosystem of southwestern Georgia. We assessed the pre- and post-emergent properties of nine herbicides on ten species of grasses, legumes, and composites. For each species, we examined phytotoxic responses to two rates (low rate and high rate) of herbicide at three stages of plant growth: 0 (pre-emergent), 30, and 60 d post-emergent. Plants were visually rated for leaf damage 30 d after herbicide application to assess the phytotoxic effects of the herbicides. Plants were then harvested, dried, and weighed. Regardless of herbicide application rate or age of plant, legumes were extremely vulnerable to applications of aminopyralid, triclopyr, and hexazinone. Most pre-emergent grasses were vulnerable to triclopyr when applied at the high rate. Most 30-day-old grasses were killed when treated with the high rate of hexazinone. Our results indicate that several native species are more sensitive to herbicide application than expected based on the below maximum label rates used and the specificity implied on the herbicide labeling.

Evaluation of the safety of spinosad and milbemycin 5-oxime orally administered to Collies with the MDR1 gene mutation

To determine whether signs of avermectin (AVM)-milbemycin (MB) toxicosis would be evident in AVM-MB-sensitive Collies after treatment with an experimental formulation of spinosad alone or spinosad combined with MB 5-oxime (MBO) at doses up to 5 and 10 times the MBO maximum label dose. 20 adult Collies homozygous or heterozygous for the MDR1 gene mutation that had signs of toxicosis after oral administration of ivermectin. On the basis of AVM-MB sensitivity score, each dog was assigned in a randomized block design to 1 of 5 treatment groups (control group, 300 mg of spinosad/kg [5 times maximum label dose], 180 mg of spinosad/kg with 3 mg of MBO/kg [3 times maximum MBO label dose], 300 mg of spinosad/kg with 5 mg of MBO/kg, and 300 mg of spinosad/kg with 10 mg of MBO/kg). Treatments were administered orally as a sequence of single doses during 5 consecutive days. After a 28-day washout period, treatment sequences were repeated. Posttreatment observation and scoring by blinded observers were conducted to specifically include neurologic abnormalities typical of AVM-MB toxicosis, such as signs of depression, ataxia, mydriasis, and hypersalivation. No signs of AVM-MB toxicosis were attributed to treatment in any dog during the study. Results indicated that oral administration of spinosad at 300 mg/kg alone or in combination with MBO at doses up to 10 mg/kg did not cause signs of AVM-MB toxicosis in AVM-MB-sensitive dogs with the MDR1 gene mutation.

Limited Efficacy of Commercially Formulated Essential Oils on Vegetation against Female Aedes albopictus and Culex quinquefasciatus

J. Agric. Urban Entomol. 27: 54-60 (2010/2011) ABSTRACT To address inquiries from the general public and Florida mosquito control programs on the effectiveness of natural products to control resting adult mosquitoes on vegetation, we conducted a study that evaluated the toxicity of several commercially available products containing plant essential oils against female Aedes albopictus (Skuse) and Culex quinquefas- ciatus Say (Diptera: Culicidae) when applied to the leaves of a common Florida landscape shrub, the southern wax myrtle, Myrica cerifera L. (Myricaceae). The products tested were EcoExempt MCE, Misting System ConcentrateE, Mosquito BarrierE, No-See-Um Organic RepellentE, and Orange GuardE. All products were applied at maximum label rates via a hand pump sprayer and compared with a commercial formulation of synergized pyrethrins, RiptideE, as a standard. Excised leaf bioassays revealed that the essential oil formulations provided less than 10% mortality to both mosquito species with essentially no residual activity beyond 24 h. Riptide provided significantly greater mortality, approximately 25% and 41%, at 24 h for Ae. albopictus and Cx. quinquefasciatus, respectively, but this product did not exhibit residual activity beyond 24 h on treated leaves. We conclude that vegetative surfaces treated with the above products containing essential oils would not prove sufficiently effective to control mosquitoes when compared with conventional pyrethroid insecticides labeled for the same purpose.

The [formula omitted]-labelling problem for trees

Let h ≥ 1 be an integer. An L ( h , 1 , 1 ) -labelling of a (finite or infinite) graph is an assignment of nonnegative integers (labels) to its vertices such that adjacent vertices receive labels with difference at least h , and vertices distance 2 or 3 apart receive distinct labels. The span of such a labelling is the difference between the maximum and minimum labels used, and the minimum span over all L ( h , 1 , 1 ) -labellings is called the λ h , 1 , 1 -number of the graph. We prove that, for any integer h ≥ 1 and any finite tree T of diameter at least 3 or infinite tree T of finite maximum degree, max { max u v ∈ E ( T ) min { d ( u ) , d ( v ) } + h − 1 , Δ 2 ( T ) − 1 } ≤ λ h , 1 , 1 ( T ) ≤ Δ 2 ( T ) + h − 1 , and both lower and upper bounds are attainable, where Δ 2 ( T ) is the maximum total degree of two adjacent vertices. Moreover, if h is less than or equal to the minimum degree of a non-pendant vertex of T , then λ h , 1 , 1 ( T ) ≤ Δ 2 ( T ) + h − 2 . In particular, Δ 2 ( T ) − 1 ≤ λ 2 , 1 , 1 ( T ) ≤ Δ 2 ( T ) . Furthermore, if T is a caterpillar and h ≥ 2 , then max { max u v ∈ E ( T ) min { d ( u ) , d ( v ) } + h − 1 , Δ 2 ( T ) − 1 } ≤ λ h , 1 , 1 ( T ) ≤ Δ 2 ( T ) + h − 2 with both lower and upper bounds achievable.

Recommendations for Evaluation of Prosthetic Valves With Echocardiography and Doppler Ultrasound: A Report From the American Society of Echocardiography's Guidelines and Standards Committee and the Task Force on Prosthetic Valves, Developed in Conjunction With the American College of Cardiology Cardiovascular Imaging Committee, Cardiac Imaging Committee of the American Heart Association, the European Association of Echocardiography, a registered branch of the

Recommendations for Evaluation of Prosthetic Valves With Echocardiography and Doppler Ultrasound: A Report From the American Society of Echocardiography's Guidelines and Standards Committee and the Task Force on Prosthetic Valves, Developed in Conjunction With the American College of Cardiology Cardiovascular Imaging Committee, Cardiac Imaging Committee of the American Heart Association, the European Association of Echocardiography, a registered branch of the

Environmental Factors Affecting Efficacy of Bifenthrin-treated Vegetation for Mosquito Control

The use of pesticide-treated vegetation as a barrier for control of nuisance and disease-bearing mosquitoes has become an option for mosquito management for home owners and public health and mosquito control professionals. Potted wax myrtle and azalea plants were treated with bifenthrin (0.79% AI) at maximum label rate using backpack and electrostatic sprayers and exposed to various treatments that could affect the residual degradation of the applied pesticides. Treatments included leaf aspect, simulated rainfall, shade, and natural sun exposure with the residual effectiveness of leaves examined in tarsal contact Petri dish assays using laboratory-reared Aedes aegypti. There was no significant difference in efficacy between the adaxial (top) or abaxial (bottom) surfaces of electrostatically or backpack-treated leaves. Significant differences existed between application method, plant species, and exposure with most significant effects between weeks 1 and 4. Simulated heavy rainfalls applied 3 times weekly reduced knockdown by leaves treated with electrostatic and backpack methods with reductions seen as soon as 1 wk after treatment. Reductions were seen with both wax myrtle and azalea leaves and after 1, 4, and 24 h contact of mosquitoes to leaves. Placement of plants with full exposure to sunlight also significantly reduced efficacy compared to plants placed in the shade. Differences were observed most often for 4 and 24 h knockdown counts, and significant decreases were seen from week 4 onwards. Clearly factors such as rain and exposure to sun impact degradation of efficacy of bifenthrin-treated vegetation in the field. Degradation of bifenthrin efficacy was slowest in sites protected from rain and sun, which coincide with preferred resting site locations for many mosquito species.

Intensity of Anthracnose on Three Wintercreeper Euonymus Cultivars as Influenced by Fungicide Program

Abstract Plants of three cultivars of wintercreeper euonymus (Euonymus fortunei (Turcz.) Hand.-Mazz. ‘Emerald Gaiety’, ‘Emerald ‘n Gold’ and ‘Canadale Gold’) in containers were sprayed at 7-or 14-day intervals depending on label directions with mancozeb, propiconazole, or thiophanate methyl alone or in tank mixes of two fungicides to determine efficacy in controlling anthracnose symptoms caused by Colletotrichum gloeosporioides (Penz.) Penz. &amp; Sacc. Each fungicide was applied at the maximum label rate and half the maximum label rate when applied alone or at the maximum label rate when applied in combination. Plants were rated for disease symptoms monthly at two sites in 2002 and at one site in 2006. At Stillwater, disease ratings were typically lowest on ‘Emerald Gaiety’ and highest on ‘Emerald ‘n Gold’ on all rating dates in both years. Plants of all three cultivars and in all fungicide treatments at Stillwater had sufficient disease symptoms in July, August and September of both years to be considered nonsalable. When applied alone, mancozeb typically provided better anthracnose control than propiconazole or thiophanate methyl. Disease ratings from plants receiving any fungicide mixture were generally similar to those of plants receiving mancozeb alone. At Park Hill, disease ratings differed among cultivars only in August and September, and ratings did not differ among fungicide treatments on any rating date. Disease severity was substantially less at Park Hill than Stillwater in 2002, presumably the result of greater shade intensity and lower temperatures.

Development and Characterization of 99mTc-timolol Maleate for Evaluating Efficacy of In Situ Ocular Drug Delivery System

In situ gel-forming systems have drawn much attention of current researchers to overcome the poor bioavailability from the conventional eye drops. The present work described formulation and pharmacoscintigraphic evaluation of timolol-maleate-loaded chitosan/hydroxy propyl methyl cellulose (HPMC)-based polymer matrix for enhanced ocular retention. Chitosan and HPMC ratio was optimized and formulation was characterized for various in vitro parameters. The ocular retention was studied on New Zealand rabbits by gamma scintigraphy, which is a very simple and noninvasive technique. For scintigraphy study, the drug timolol maleate was radiolabeled (99m)Tc by direct labeling method using SnCl(2).2H(2)O as reducing agent. The labeling procedure was optimized to get maximum labeling efficiency (>98%). In vitro stability of the radiolabeled drug ((99m)Tc-timolol maleate complex) was checked and it was found to be stable for up to 24 h. Plain drug eliminates rapidly as significant activity was recorded in kidney and bladder after 2 h of ocular administration. It was evident from the scintigraphic images and the time-activity curve plotted from the data that the plain drug solution cleared very rapidly from the corneal region and reached into systemic circulation via nasolachrymal drainage system, as significant activity was recorded in kidney and bladder after 2 h of ocular administration. Developed formulation cleared at a slow rate and remained at corneal surface for longer time duration. No radioactivity was observed in systemic circulation after 2 h. Ocular irritation of the developed formulation was also checked by hen's egg chorioallantoic membrane test and formulation was found to be practically nonirritant. The study signified the potential of gamma scintigraphy in evaluation of novel drug delivery systems in a noninvasive manner.

Catching the Trend: A Framework for Clustering Concept-Drifting Categorical Data

Sampling has been recognized as an important technique to improve the efficiency of clustering. However, with sampling applied, those points that are not sampled will not have their labels after the normal process. Although there is a straightforward approach in the numerical domain, the problem of how to allocate those unlabeled data points into proper clusters remains as a challenging issue in the categorical domain. In this paper, a mechanism named MAximal Resemblance Data Labeling (abbreviated as MARDL) is proposed to allocate each unlabeled data point into the corresponding appropriate cluster based on the novel categorical clustering representative, namely, N-Nodeset Importance Representative (abbreviated as NNIR), which represents clusters by the importance of the combinations of attribute values. MARDL has two advantages: (1) MARDL exhibits high execution efficiency, and (2) MARDL can achieve high intracluster similarity and low intercluster similarity, which are regarded as the most important properties of clusters, thus benefiting the analysis of cluster behaviors. MARDL is empirically validated on real and synthetic data sets and is shown to be significantly more efficient than prior works while attaining results of high quality.