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Insects are major actors in Earth’s ecosystems and their recent decline in abundance and diversity is alarming. The monitoring of insects is paramount to understand the cause of this decline and guide conservation policies. In this contribution, an infrared laser-based system is used to remotely monitor the biomass density of flying insects in the wild. By measuring the optical extinction caused by insects crossing the 36-m long laser beam, the Entomological Bistatic Optical Sensor System used in this study can evaluate the mass of each specimen. At the field location, between July and December 2021, the instrument made a total of 262,870 observations of insects for which the average dry mass was 17.1 mg and the median 3.4 mg. The daily average mass of flying insects per meter cube of air at the field location has been retrieved throughout the season and ranged between near 0 to 1.2 mg/m3. Thanks to its temporal resolution in the minute range, daily variations of biomass density have been observed as well. These measurements show daily activity patterns changing with the season, as large increases in biomass density were evident around sunset and sunrise during Summer but not during Fall.

Cage subsidence remains a major complication after spinal surgery. The goal of this study was to compare the subsidence performance of three modern porous cage designs.Three porous cages were evaluated: a porous titanium cage, a porous polyetheretherketone cage and a truss titanium cage. Mechanical testing was performed for each cage per the American Society for Testing and Materials F2077 and F2267 standards to evaluate cage stiffness and block stiffness, and per a novel clinically relevant dynamic subsidence testing method simulating cyclic spine loading during 3-months postoperatively to evaluate the subsidence displacement.The porous polyetheretherketone cage demonstrated the lowest cage stiffness (21.0 ± 1.1 kN/mm), less than half of both titanium cages (truss titanium cage, 49.1 kN/mm; porous titanium cage, 43.6 kN/mm). The block stiffness was greatest for the porous titanium cage (2867.7 ± 105.3 N/mm), followed by the porous polyetheretherketone (2563.4 ± 72.9 N/mm) and truss titanium cages (2213.7 ± 21.8 N/mm). The dynamic subsidence displacement was greatest for the truss titanium cage, which was 1.5 and 2.5 times the subsidence displacement as the porous polyetheretherketone and porous titanium cages respectively.Specific porous cage design plays a crucial role in the cage subsidence performance, to a greater degree than the selection of cage materials. A porous titanium cage with body lattice and microporous endplates significantly outperformed a truss titanium cage with a similar cage stiffness in subsidence performance, and a porous polyetheretherketone cage with half of its stiffness.

Pesticide resistance in arthropod vectors of disease agents is a growing issue globally. Despite the importance of resistance monitoring to inform mosquito control programs, no regional monitoring programs exist in the United States. The Northeastern Regional Center for Excellence in Vector-Borne Diseases (NEVBD) is a consortium of researchers and public health practitioners with a primary goal of supporting regional vector control activities. NEVBD initiated a pesticide resistance monitoring program to detect resistant mosquito populations throughout the northeastern United States. A regionwide survey was distributed to vector control agencies to determine needs and refine program development and in response, a specimen submission system was established, allowing agencies to submit Culex pipiens (L.) (Diptera:Culicidae) and Aedes albopictus (Skuse) (Diptera: Culicidae) for pesticide resistance testing. NEVBD also established larvicide resistance diagnostics for Bacillus thuringiensis israelensis (Bti) and methoprene. Additional diagnostics were developed for Cx. pipiens resistance to Lysinibacillus sphaericus. We received 58 survey responses, representing at least one agency from each of the 13 northeastern U.S. states. Results indicated that larvicides were deployed more frequently than adulticides, but rarely paired with resistance monitoring. Over 18,000 mosquitoes were tested from six states. Widespread low-level (1 × LC-99) methoprene resistance was detected in Cx. pipiens, but not in Ae. albopictus. No resistance to Bti or L. sphaericus was detected. Resistance to pyrethroids was detected in many locations for both species. Our results highlight the need for increased pesticide resistance testing in the United States and we provide guidance for building a centralized pesticide resistance testing program.

Background Management of Aedes albopictus and Ae. aegypti is challenging in large part due to the cryptic nature of their larval habitats. Autodissemination, using conspecific species to transfer pesticide, is unable to provide proactive control. Here we report results from a new hypothesis, heterodissemination, wherein females of the cohabiting non-biting midge, Chironomus decorus, reared in the laboratory, treated with pyriproxyfen, and released to transfer lethal concentrations to shared mosquito larval habitats. Results Pyriproxyfen-impregnated oil and powder formulations were developed. The average payload for each female midge treated with oil followed by powder formulations was 5.07 ± 0.92 μg of active ingredient or 1660 times the median lethal concentration (LC50 ) for Ae. albopictus or Ae. aegypti in 200 mL of water. Subsequent residue analysis showed pyriproxyfen transference from chironomids, treated with oil formulation only, into water-holding containers up to 2.06 ppb or 171.7 times the LC50 . Releasing 20 laboratory reared and contaminated Chironomus decorus into a small room resulted in 80.42 ± 0.67% and 75.67 ± 3.14% Ae. albopictus pupal mortality in open and cryptic sentinel ovicups, respectively. Container water volumes ranging up to 4 L did not affect efficacy. In a large field cage, 90.3 ± 2.5% Ae. albopictus mortality was resulted from releasing 100 treated female midges. Releasing 400 contaminated midges into a residential backyard resulted in 74.3% pupal mortality in sentinel ovicups. Conclusions Room, large field cage and field release trials demonstrated that adult midges reared and treated in the laboratory transfer highly lethal concentrations of pyriproxyfen to Ae. albopictus container habitats. Heterodissemination provides a potential approach for precision, proactive mosquito control, which may draw attention for further studies. © 2020 Society of Chemical Industry.

The objective of the study was to quantify the effect of cage material (titanium-alloy vs. polyetheretherketone or PEEK) and design (porous vs. solid) on subsidence and osseointegration.Three lateral cages (solid PEEK, solid titanium, and 3-dimension-printed porous titanium cages) were evaluated for cage stiffness, subsidence compression stiffness, and dynamic subsidence displacement under simulated postoperative spine loading. Dowel-shaped implants made of grit-blasted solid titanium alloy (solid titanium) and porous titanium were fabricated using commercially available processes. Samples were processed for mechanical push-out testing and polymethylmethacrylate histology following an established ovine bone implantation model.The solid titanium cage exhibited the greatest stiffness (57.1 ± 0.6 kN/mm), followed by the porous titanium cage (40.4 ± 0.3 kN/mm) and the solid PEEK cage (37.1 ± 1.2 kN/mm). In the clinically relevant dynamic subsidence, the porous titanium cage showed the least amount of subsidence displacement (0.195 ± 0.012 mm), significantly less than that of the solid PEEK cage (0.328 ± 0.020 mm) and the solid titanium cage (0.538 ± 0.027 mm). Bony on-growth was noted histologically on all implant materials; however, only the porous titanium supported bony ingrowth with marked quantities of bone formed within the interconnected pores through 12 weeks. Functional differences in osseointegration were noted between groups during push-out testing. The porous titanium showed the highest maximum shear stress at 12 weeks and was the only group that demonstrated significant improvement (4-12 weeks).The choice of material and design is critical to cage mechanical and biological performances. A porous titanium cage can reduce subsidence risk and generate biological stability through bone on-growth and ingrowth.

We developed an index for use by New Jersey counties to measure West Nile virus (WNV) transmission risk to the human population. We used a latent profile analysis to develop the index, identifying categories of environmental conditions associated with WNV transmission risk to humans. The final model included 4 indicators of transmission risk: mosquito abundance and minimum field infection rate, temperature, and human case count. We used data from 2004 to 2018 from all 21 New Jersey counties aggregated into 11 2-wk units per county per year (N = 3,465). Three WNV risk classes were identified. The Low Risk class had low levels of all variables. The Moderate Risk class had high abundance, average temperature levels, and low levels of the other variables. The High Risk class had substantially above average human case likelihood, average temperature, and high mosquito infection rates. These results suggest the presence of 3 distinct WNV risk profiles, which can be used to guide the development of public health actions intended to mitigate WNV transmission risk to the human population.

Although small in size, insects are a quintessential part of terrestrial ecosystems due to their large number and diversity. While captured insects can be thoroughly studied in laboratory conditions, their population dynamics and abundance in the wild remain largely unknown due to the lack of accurate methodologies to count them. Here, we present the results of a field experiment where the activity of insects has been monitored continuously over 3 months using an entomological stand-off optical sensor (ESOS). Because its near-infrared laser is imperceptible to insects, the instrument provides an unbiased and absolute measurement of the aerial density (flying insect/m3) with a temporal resolution down to the minute. Multiple clusters of insects are differentiated based on their wingbeat frequency and ratios between wing and body optical cross-sections. The collected data allowed for the study of the circadian rhythm and daily activities as well as the aerial density dynamic over the whole campaign for each cluster individually. These measurements have been compared with traps for validation of this new methodology. We believe that this new type of data can unlock many of the current limitations in the collection of entomological data, especially when studying the population dynamics of insects with large impacts on our society, such as pollinators or vectors of infectious diseases.

BACKGROUND Given the lack of vaccines for most vector-borne diseases, vector control is often the primary option for disease control. Aedes albopictus are difficult to control because the immatures primarily develop in containers ubiquitous in residential properties. Conventional adulticide campaigns often result in brief, rebounding population declines, so incorporating new techniques into an integrated pest management program is imperative. We performed combined area-wide applications of the larvicides Bacillus thuringiensis var. israelensis and pyriproxyfen with the adulticide sumithrin and prallethrin to achieve extended suppression of Ae. albopictus populations in Trenton, NJ, USA. We deployed bioassay cups to assess the spatial penetration and efficacy of the applications. RESULTS Inhibition of adult emergence was significantly higher in the treatment bioassay cups than in laboratory controls (z = 4.65, P < 0.0001) and field control bioassay cups (z = 8.93, P < 0.0001). We observed a lower trend in adult numbers following season-long combined application of pyriproxyfen and adulticide, with numbers of adult Ae. albopictus at the treatment site up to five times lower than at the control site. CONCLUSION Pyriproxyfen is a powerful mosquito larvicide and pupacide with low mammalian toxicity that shows promise for area-wide vehicle-mounted (either ground or airborne) applications. © 2018 Society of Chemical Industry.

BACKGROUND Control of the container-inhabiting mosquito, Aedes albopictus, is difficult using conventional methods due to its selection of cryptic peri-domestic habitats. We evaluated whether autodissemination stations can deliver sufficient pyriproxyfen to sentinel containers to produce significant pupal mortality in different habitats such as competing oviposition sites, peri-domestic habitats, junkyards and tire piles. We also tested how far the pesticide could be transferred over a 200-m range. RESULTS Autodissemination stations performed effectively for 8–12 weeks under field conditions. Pupal mortality was reduced in sentinel cups with high-competing oviposition habitats (5 versus 20) in isolated plots; however, similar results were not seen in residential areas. Increasing the number of stations per plot (from 1 to 4) enhanced the efficacy. Peri-domestic habitat trials showed the highest pupal mortality (50.4%) and site contamination with pyriproxyfen (82.2%) among the trials. Autodissemination stations were able to contaminate habitats in a junkyard (50.0%) and tire piles (40.2%). Pyriproxyfen was detected in sentinel cups up to 200 m from stations. Detection of pyriproxyfen by residue analysis (0.005–0.741 µg L−1) in field samples confirmed the transfer of the insect growth regulator. CONCLUSION Autodissemination stations have shown promising potential as a novel pest management tool against container mosquitoes in field trials in different habitats confronted by mosquito control personnel. © 2017 Society of Chemical Industry

We constructed an electric multi-rotor autonomous unmanned aerial system (UAS) to perform mosquito control activities. The UAS can be equipped with any of four modules for spraying larvicides, dropping larvicide tablets, spreading larvicide granules, and ultra-low volume spraying of adulticides. The larvicide module sprayed 124 μm drops at 591 mL/min over a 14 m swath for a total application rate of 1.6 L/ha. The tablet module was able to repeatedly deliver 40-gram larvicide tablets within 1.1 m of the target site. The granular spreader covered a 6 m swath and treated 0.76 ha in 13 min at an average rate of 1.8 kg/ha. The adulticide module produced 16 μm drops with an average deposition of 2.6 drops/mm2. UAS pesticide applications were made at rates prescribed for conventional aircraft, limited only by the payload capacity and flight time. Despite those limitations, this system can deliver pesticides with much greater precision than conventional aircraft, potentially reducing pesticide use. In smaller, congested environments or in programs with limited resources, UAS may be a preferable alternative to conventional aircraft.

We constructed an electric multi-rotor autonomous unmanned aerial system (UAS) to perform mosquito control activities. The UAS can be equipped with any of four modules for spraying larvicides, dropping larvicide tablets, spreading larvicide granules, and ultra-low volume spraying of adulticides. The larvicide module sprayed 124 μm drops at 591 mL/min over a 14 m swath for a total application rate of 1.6 L/ha. The tablet module was able to repeatedly deliver 40-gram larvicide tablets within 1.1 m of the target site. The granular spreader covered a 6 m swath and treated 0.76 ha in 13 min at an average rate of 1.8 kg/ha. The adulticide module produced 16 μm drops with an average deposition of 2.6 drops/mm2. UAS pesticide applications were made at rates prescribed for conventional aircraft, limited only by the payload capacity and flight time. Despite those limitations, this system can deliver pesticides with much greater precision than conventional aircraft, potentially reducing pesticide use. In smaller, congested environments or in programs with limited resources, UAS may be a preferable alternative to conventional aircraft.

Determining the molecular mechanisms that contribute to trinucleotide repeat (TNR) expansions is essential to understanding the origin of genetically inherited diseases, such as Huntington's disease, and to inform efforts in developing therapeutic treatments. As one resource to probe the mechanisms of TNR expansions, we describe an expansion assay in human tissue culture cells. The cell line SVG-A, derived from human astrocytes, has the important property of supporting expansions in culture, unlike many cell lines derived from patients. SVG-A cells are also amenable to standard genetic and biochemical techniques such as siRNA, CRISPR-Cas9 and enzymatic inhibitors. This combination of features allows for mechanistic studies of TNR expansions, using the quantitative genetic assay described here as a readout. The SVG-A assay has correctly identified key proteins that drive expansions and it has facilitated testing of enzymatic inhibitors that suppress expansions as potential therapeutics. This chapter describes how repeat expansions are detected, visualized, and quantified.

Trinucleotide repeat (TNR) tracts are inherently unstable during DNA replication, leading to repeat expansions and/or contractions. Expanded tracts are the cause of over 40 neurodegenerative and neuromuscular diseases. In this chapter, we focus on the (CAG)

Determining the molecular mechanisms that contribute to trinucleotide repeat (TNR) expansions is essential to understanding the origin of genetically inherited diseases, such as Huntington's disease, and to inform efforts in developing therapeutic treatments. As one resource to probe the mechanisms of TNR expansions, we describe an expansion assay in human tissue culture cells. The cell line SVG-A, derived from human astrocytes, has the important property of supporting expansions in culture, unlike many cell lines derived from patients. SVG-A cells are also amenable to standard genetic and biochemical techniques such as siRNA, CRISPR-Cas9 and enzymatic inhibitors. This combination of features allows for mechanistic studies of TNR expansions, using the quantitative genetic assay described here as a readout. The SVG-A assay has correctly identified key proteins that drive expansions and it has facilitated testing of enzymatic inhibitors that suppress expansions as potential therapeutics. This chapter describes how repeat expansions are detected, visualized, and quantified.

Trinucleotide repeat (TNR) tracts are inherently unstable during DNA replication, leading to repeat expansions and/or contractions. Expanded tracts are the cause of over 40 neurodegenerative and neuromuscular diseases. In this chapter, we focus on the (CAG)n and (CTG)n repeat sequences that, when expanded, lead to Huntington's disease (HD) and myotonic dystrophy type 1 (DM1), respectively, as well as a number of other neurodegenerative diseases. TNR tracts in most individuals are relatively small and stable in terms of length. However, TNR tracts become increasingly prone to expansion as tract length increases, eventually leading to very long tracts that disrupt coding (e.g. HD) or noncoding (e.g., DM1) regions of the genome. It is important to understand the early stages in TNR expansions, that is, the transition from small, stable lengths to susceptible threshold lengths. We describe PCR-based in vivo assays, using the model system Saccharomyces cerevisiae, to determine and characterize the dynamic behavior of TNR tracts in the stable and threshold ranges. We also describe a simple in vitro system to assess tract dynamics during 5' single-stranded DNA (ssDNA) flap processing and to assess the role of different DNA metabolism proteins in these dynamics. These assays can ultimately be used to determine factors that influence the early stages of TNR tract expansion.

Improving the survey of mosquito populations is of the utmost importance to further enhance mitigation techniques that protect human populations from mosquito‐borne diseases. While mosquito populations are generally studied using physical traps, stand‐off optical sensors allow to study insect ecosystems with potentially better spatial and temporal resolution. This can be greatly beneficial to eco‐epidemiological models and various mosquito control programs. In this contribution, we demonstrate that the gravidity of female mosquitoes can be identified from changes in their spectral and polarimetric backscatter cross sections. Among other predictive variables, the wing beat frequency and the depolarization ratio of the mosquito body allows for the identification of gravid females with a precision and recall of 86% and 87%, respectively. Since female mosquitoes need a blood meal to become gravid, statistics on gravidity is of prime importance as only females that have been gravid might carry infectious diseases. In addition, it allows to detect possible breeding habitat, predict a potential increase in the mosquito population and provide a better overall understanding of the ecosystem dynamics. As a result, targeted and localized mitigation techniques can be used, reducing the cost and improving the efficiency of mosquito population control., Improving the survey of mosquito populations is of the utmost importance to further enhance mitigation techniques that protect human populations from mosquito‐borne diseases. This work demonstrates that gravid mosquitoes (carrying eggs) can be identified from changes in their spectral and polarimetric backscatter cross sections. Entomological lidars and/or optical sensors can take advantage of these optical properties to improve their ability to remotely monitor insect ecosystems.

DNA-binding proteins search for specific targets via facilitated diffusion along a crowded genome. However, little is known about how crowded DNA modulates facilitated diffusion and target recognition. Here we use DNA curtains and single-molecule fluorescence imaging to investigate how Msh2–Msh3, a eukaryotic mismatch repair complex, navigates on crowded DNA. Msh2–Msh3 hops over nucleosomes and other protein roadblocks, but maintains sufficient contact with DNA to recognize a single lesion. In contrast, Msh2–Msh6 slides without hopping and is largely blocked by protein roadblocks. Remarkably, the Msh3-specific mispair-binding domain (MBD) licences a chimeric Msh2–Msh6(3MBD) to bypass nucleosomes. Our studies contrast how Msh2–Msh3 and Msh2–Msh6 navigate on a crowded genome and suggest how Msh2–Msh3 locates DNA lesions outside of replication-coupled repair. These results also provide insights into how DNA repair factors search for DNA lesions in the context of chromatin., DNA-binding proteins need to scan the genome to find their targets though how this occurs in the crowded nuclear environment is poorly understood. Here the authors use single-molecular fluorescence to show the repair complex Msh2-Msh3 can hop over blocks that impede the sliding complex Msh2-Msh6.

The surveillance of mosquito populations is paramount in the fight against mosquito-borne diseases that affect millions of people every year. Evaluating the efficiency of mitigation methods requires extensive and long-term surveys which can be costly and time consuming. The recent development of optical sensors give access to alternative methods for entomological monitoring but require efficient classification algorithms to be successful. In this contribution, supervised machine learning algorithms such as Linear Discriminant Analysis, Decision Trees, Support Vector Machine, K-Nearest Neighbors and Naive Bayes are compared for the identification of mosquitoes through optical signals. Based on predictor variables derived from the wing beat frequency and optical cross section of mosquitoes, these algorithms were trained to perform different classification tasks: the identification of species, sex and/or gravidity of mosquitoes present in New Jersey, USA. Results shows that the most polyvalent machine learning algorithm for mosquito identification is Support Vector Machine that performs on average over all tasks between 0.65 and 7.3% better than other algorithms. Moreover, Support Vector Machine is the algorithm that best performed for the most complex tasks, more than 2% above the second best, it is therefore the most suited for real-world study where several species of mosquito can be expected at a single location. A close second is Linear Discriminant Analysis that is only outperformed by Support Vector Machine by 0.65% over all tasks and is the most performant when studying mosquito gravidity. Finally, Decision Trees algorithm has reached almost perfection in identifying the sex of a single mosquito species with 99.9% accuracy which is 1.3% more than the second best performing algorithm on this task. These results demonstrate that optical sensors, coupled with machine learning, can be a viable alternative or complementary methodology for the monitoring of mosquito populations. Furthermore, this methodology can perform non-intrusive, automatic, time-resolved measurements of insect population dynamics over extended periods of time without the need for laboratory analysis of captured specimens as in most traditional survey methods.

Mosquito-borne diseases are a major challenge for Human health as they affect nearly 700 million people every year and result in over 1 million deaths. Reliable information on the evolution of population and spatial distribution of key insects species is of major importance in the development of eco-epidemiologic models. This paper reports on the remote characterization of flying mosquitoes using a continuous-wave infrared optical remote sensing system. The system is setup in a controlled environment to mimic long-range lidars, mosquitoes are free flying at a distance of ~ 4 m from the collecting optics. The wing beat frequency is retrieved from the backscattered light from mosquitoes transiting through the laser beam. A total of 427 transit signals have been recorded from three mosquito species, males and females. Since the mosquito species and gender are known a priori, we investigate the use of wing beat frequency as the sole predictor variable for two Bayesian classifications: gender alone (two classes) and species/gender (six classes). The gender of each mosquito is retrieved with a 96.5% accuracy while the species/gender of mosquitoes is retrieved with a 62.3% accuracy. Known to be an efficient mean to identify insect family, we discuss the limitations of using wing beat frequency alone to identify insect species.

Barrier applications, treating vegetation and other potential mosquito resting areas with residual pesticides, have become standard practice for commercial pest management professionals offering mosquito control services. These treatments are generally effective in reducing numbers of the Asian tiger mosquito, Aedes albopictus (Skuse). In the temperate climates, adult Ae. albopictus populations are naturally eliminated each winter and must be grown from diapausing eggs the following spring. Therefore, early-season control interventions timed before populations rebound may further reduce population growth compared with interventions that take place after the population has peaked. We compared Early (1 June) barrier applications of lambda-cyhalothrin (Demand CS) mixed with the insect growth regulator pyriproxyfen (Archer IGR) to Late applications (31 July) in urban and suburban residential parcels in New Jersey. These applications resulted in 43 and 51% reductions in adult Ae. albopictus populations in the Early and Late intervention study parcels, respectively, when compared with the untreated Controls. Indirect applications of pyriproxyfen (i.e., rainwater runoff transferring pesticide) to potential larval habitat did not cause mortality in laboratory larval bioassays but direct mist applications of the Archer and Demand combination to larval habitats led to elevated larval mortality over a 6-wk period. The Early-season intervention offered no advantage in efficacy on adult populations compared with the Late-season intervention, which targeted peak mosquito populations. Our study provides support for the efficacy of barrier applications and illustrates the importance of timing barrier treatments to coincide with established Ae. albopictus action thresholds.

Mosquito-borne diseases are a major challenge for Human health as they affect nearly 700 million people every year. Monitoring insects is generally done through trapping methods that are tedious to set up, costly and present scientific biases. Entomological lidars are a potential solution to remotely count and identify mosquito species and gender in real-time. In this contribution, a dual-wavelength polarization sensitive lidar is used in laboratory conditions to retrieve the wingbeat frequency as well as optical properties of flying mosquitoes transiting through the laser beam. From the lidar signals, predictive variables are retrieved and used in a Bayesian classification. This paper focuses on determining the relative importance of the predictive variables used in the classification. Results show a strong dominance of the wingbeat frequency, the impact of predictive variables based on depolarization and backscattering ratios are discussed, showing a significant increase in classification accuracy.

Given the lack of vaccines for most vector-borne diseases, vector control is often the primary option for disease control. Aedes albopictus are difficult to control because the immatures primarily develop in containers ubiquitous in residential properties. Conventional adulticide campaigns often result in brief, rebounding population declines, so incorporating new techniques into an integrated pest management program is imperative. We performed combined area-wide applications of the larvicides Bacillus thuringiensis var. israelensis and pyriproxyfen with the adulticide sumithrin and prallethrin to achieve extended suppression of Ae. albopictus populations in Trenton, NJ, USA. We deployed bioassay cups to assess the spatial penetration and efficacy of the applications.Inhibition of adult emergence was significantly higher in the treatment bioassay cups than in laboratory controls (z = 4.65, P0.0001) and field control bioassay cups (z = 8.93, P0.0001). We observed a lower trend in adult numbers following season-long combined application of pyriproxyfen and adulticide, with numbers of adult Ae. albopictus at the treatment site up to five times lower than at the control site.Pyriproxyfen is a powerful mosquito larvicide and pupacide with low mammalian toxicity that shows promise for area-wide vehicle-mounted (either ground or airborne) applications. © 2018 Society of Chemical Industry.

In the original publication of the article, many references were cited incorrectly. Now, the original article has been corrected accordingly.

Marker dyes are often mixed with liquid insecticide formulations prior to field applications to accurately determine the characteristics and penetration of droplets into targeted habitats. We have been using FD&C Red 40 Granular DM food dye at the rate of 20 g/liter in liquid solutions of Bacillus thuringiensis israelensis (Bti) for area-wide larvicide applications against the Asian tiger mosquito, Aedes albopictus. The Bti and dye mix ratio has been recommended by pesticide manufacturers for testing under operational conditions, but no data exist on the effects of the dye itself on mosquito larvae. We tested the effects of the FD&C Red 40 food dye in laboratory bioassays against different strains of Ae. albopictus (New Jersey and Maryland) and Culex pipiens pipiens (Utah) at rates of 0.039 to 80.0 g/liter. We also conducted field application trials to measure dye concentrations up to 100 m downwind when mixed and applied according to manufacturer instructions. In laboratory bioassays, we found that mean survival in cups with dye were significantly different from the controls beginning at 10.0 g/liter for New Jersey Ae. albopictus and at 20.0 g/liter for Maryland Ae. albopictus and Utah Cx. p. pipiens. In field application trials, we recorded a maximum volume density of 1,152.8 nl/cm(2) and calculated the maximum concentration of dye at 9.09 × 10(-3) g/liter. Our results showed that although we detected greater effects of dye on Ae. albopictus in New Jersey experiments than Ae. albopictus in Maryland and Cx. p. pipiens from Utah, concentrations of the dye during operational applications were at least 1,100 times below concentrations that exhibited toxic effects for either species in the laboratory, suggesting that the dye will not interfere with accuracy of field bioassays. Our results conclusively demonstrate that the addition of the FD&C Red 40 marker dye does not alter the efficacy of the pesticide formulation by skewing results, but rather provides a valuable addition to accurately determine pesticide penetration and spectrum by discriminating between intended pesticide and other potential pollutants.

Trinucleotide repeat (TNR) expansions are the underlying cause of more than 40 neurodegenerative and neuromuscular diseases, including myotonic dystrophy and Huntington’s disease, yet the pathway to expansion remains poorly understood. An important step in expansion is the shift from a stable TNR sequence to an unstable, expanding tract, which is thought to occur once a TNR attains a threshold length. Modeling of human data has indicated that TNR tracts are increasingly likely to expand as they increase in size and to do so in increments that are smaller than the repeat itself, but this has not been tested experimentally. Genetic work has implicated the mismatch repair factor MSH3 in promoting expansions. Using Saccharomyces cerevisiae as a model for CAG and CTG tract dynamics, we examined individual threshold-length TNR tracts in vivo over time in MSH3 and msh3Δ backgrounds. We demonstrate, for the first time, that these TNR tracts are highly dynamic. Furthermore, we establish that once such a tract has expanded by even a few repeat units, it is significantly more likely to expand again. Finally, we show that threshold- length TNR sequences readily accumulate net incremental expansions over time through a series of small expansion and contraction events. Importantly, the tracts were substantially stabilized in the msh3Δ background, with a bias toward contractions, indicating that Msh2-Msh3 plays an important role in shifting the expansion-contraction equilibrium toward expansion in the early stages of TNR tract expansion.

Mosquito control programs in the United States are still searching for best management practices to control the Asian tiger mosquito, Aedes albopictus (Skuse; Diptera: Culicidae). Most intervention methods for this species are either labor intensive (e.g., source reduction) or short-term (e.g., ultra-low-volume adulticiding). We investigated the effectiveness of barrier spray pesticide applications within urban and suburban residential yards in New Jersey as a control strategy using a before-after-control-impact (BACI) approach. Applications of Demand CSR pyrethroid (9.7% AI lambda-cyhalothrin) only or combined Demand CSR and Archer IGR insect growth regulator (1.3% AI pyriproxyfen) applications resulted in significant and similar decreases in adult mosquito abundance post-treatment ranging from 78 to 74% respectively, compared with the untreated control. Both insecticides exceeded the 70% reduction threshold considered as effective for Ae. albopictus control for 2 to 4 wk. However, applications of Archer IGR alone did not reduce adult mosquito abundance. The field study results were supported by laboratory no-choice bioassays using treated leaf foliage. Our study is the first data driven evidence of the residual efficacy of barrier pesticide applications in New Jersey with lambda-cyhalothrin that provided significant reductions in adult Ae. albopictus populations for an extended duration.

Trinucleotide repeat (TNR) tracts are inherently unstable during DNA replication, leading to repeat expansions and/or contractions. Expanded tracts are the cause of over 40 neurodegenerative and neuromuscular diseases. In this chapter, we focus on the (CNG)

Trinucleotide repeat (TNR) tracts are inherently unstable during DNA replication, leading to repeat expansions and/or contractions. Expanded tracts are the cause of over 40 neurodegenerative and neuromuscular diseases. In this chapter, we focus on the (CNG)n repeat sequences that, when expanded, lead to Huntington's disease (HD), myotonic dystrophy type 1 (DM1), and a number of other neurodegenerative diseases. We describe a series of in vivo assays, using the model system Saccharomyces cerevisiae, to determine and characterize the dynamic behavior of TNR tracts that are in the early stages of expansion, i.e., the so-called threshold range. Through a series of time courses and PCR-based assays, dynamic changes in tract length can be observed as a function of time. These assays can ultimately be used to determine how genetic factors influence the process of tract expansion in these early stages.

Control of the container-inhabiting mosquito, Aedes albopictus, is difficult using conventional methods due to its selection of cryptic peri-domestic habitats. We evaluated whether autodissemination stations can deliver sufficient pyriproxyfen to sentinel containers to produce significant pupal mortality in different habitats such as competing oviposition sites, peri-domestic habitats, junkyards and tire piles. We also tested how far the pesticide could be transferred over a 200-m range.Autodissemination stations performed effectively for 8-12 weeks under field conditions. Pupal mortality was reduced in sentinel cups with high-competing oviposition habitats (5 versus 20) in isolated plots; however, similar results were not seen in residential areas. Increasing the number of stations per plot (from 1 to 4) enhanced the efficacy. Peri-domestic habitat trials showed the highest pupal mortality (50.4%) and site contamination with pyriproxyfen (82.2%) among the trials. Autodissemination stations were able to contaminate habitats in a junkyard (50.0%) and tire piles (40.2%). Pyriproxyfen was detected in sentinel cups up to 200 m from stations. Detection of pyriproxyfen by residue analysis (0.005-0.741 µg LAutodissemination stations have shown promising potential as a novel pest management tool against container mosquitoes in field trials in different habitats confronted by mosquito control personnel. © 2017 Society of Chemical Industry.

a b s t r a c t Autodissemination of insecticides is a novel strategy for mosquito management. We tested if contami- nated Aedes albopictus (Skuse) mosquitoes from a small area treated with commercial formulations (79 gm a.i. pyriproxyfen/ha) using conventional techniques, would disseminate pyriproxyfen over a wider area. Pyriproxyfen showed LC50 = 0.012 ppb for Ae. albopictus. Direct treatment and autodissemination effi- cacy was measured as a pupal mortality by conducting Ae. albopictus larval bioassay. A tire pile (n = 100 tires) treated by backpack sprayer as a point-source treatment showed higher pupal mortality in 2010 (60.8% for week 0-6) than in 2011 (38.3% for week 0-6). The sentinel containers placed for autodissem- ination in four compass directions out to 200-400 m from the tire pile showed 15.8% pupal mortality (week 1-6) in the first year, and 1.4% pupal mortality in the second year. No significant difference was detected among the distances and direction for pupal mortality. In area-wide treatments, vegetation was sprayed in checkerboard pattern (3.7% of 105 ha) using backpack sprayer in 2010 and in strips (24.8% of 94 ha) using truck-mounted ultra-low volume (ULV) sprayer in 2011. In both years, the area-wide direct treatment efficacy was lower (30.3% during 2010 and 5.3% in 2011) than point-source treatments. Autodissemination in area-wide plots was higher in 2010 (10.3%) than 2011 (2.9%). However, area-wide treatments were ineffective on field populations of Ae. albopictus as monitored by using BGS traps. We found accumulation of pyriproxyfen in the week 6 autodissemination containers in both experiments. The differences in autodissemination in 2010 and 2011 can be attributed to higher rainfall in the second year that may have eroded the pyriproxyfen from treatment surfaces and sentinel containers. Our study shows that ULV surface treatments of conventional formulation do not work for autodissemination. The effectiveness of pyriproxyfen in autodissemination may be improved by developing specific formulations to treat vegetation and tires that can load high doses on mosquitoes.

We conducted an open-field ultra-low volume efficacy bioassay using a water-based formulation AquaDuet™ (prallethrin [1%], sumithrin [5%], and piperonly butoxide [5%]) applied from a truck-mounted cold aerosol sprayer. The adulticide was applied at 90.6 ml/ha (1.23 oz/acre) and 3 replicated treatments were performed using caged Aedes albopictus collected from local wild populations. Rotating impingers and mosquito cages were placed in 3 rows stationed at 30.5 m (100 ft), 61.0 (200 ft), and 91.4 (300 ft) downwind of the spray vehicle. Initial knockdown was 95.6%, with overall mortality >99% across all distances, despite low wind conditions. Volume median diameter (Dv0.5) and droplet density were 17.4 µm and 110.5 mm2, respectively. Our open-field studies against caged Ae. albopictus demonstrate that a water-based adulticide formulation is just as efficacious as traditional oil-based formulations.

DNA binding proteins search for specific targets amidst an excess of non-target DNA largely through facilitated diffusion. While DNA is crowded with proteins in vivo, little is known about how protein roadblocks affect diffusion. Here, we use single-molecule fluorescence imaging and DNA curtains generated by nano-fabricated chromium arrays to investigate how Msh2-Msh3, a eukaryotic mismatch repair (MMR) complex, navigates on crowded DNA. We discovered that Msh2-Msh3, in contrast to the homologous protein complex Msh2-Msh6, diffuses on DNA by hopping. Furthermore, hopping allows Msh2-Msh3 to bypass protein roadblocks, including nucleosomes. Despite hopping over roadblocks, we observed that Msh2-Msh3 maintains sufficient contact with DNA to bind single DNA lesions. Remarkably, the primary Msh3 DNA binding domain, the mispair binding domain (MBD), translates the ability to hop to a Msh2-Msh6(3-MBD) chimera. This work provides a model for how Msh2-Msh3 locates lesions outside of replication-coupled MMR, provides insight into the structural pre-requisites for protein hopping, and shows how hopping may accelerate target search in the context of chromatin.

Summary Trinucleotide repeat (TNR) expansions are the underlying cause of more than 40 neurodegenerative and neuromuscular diseases, including myotonic dystrophy and Huntington's disease. Although genetic evidence points to errors in DNA replication and/or repair as the cause of these diseases, clear molecular mechanisms have not been described. Here, we focused on the role of the mismatch repair complex Msh2-Msh3 in promoting TNR expansions. We demonstrate that Msh2-Msh3 promotes CTG and CAG repeat expansions in vivo in Saccharomyces cerevisiae. Furthermore, we provide biochemical evidence that Msh2-Msh3 directly interferes with normal Okazaki fragment processing by flap endonuclease1 (Rad27) and DNA ligase I (Cdc9) in the presence of TNR sequences, thereby producing small, incremental expansion events. We believe that this is the first mechanistic evidence showing the interplay of replication and repair proteins in the expansion of sequences during lagging-strand DNA replication.

With consideration of the need for cartilage grafts of specific sizes and shapes in orthopedics and other fields, immature cartilage explants and grafts have recently been molded in vitro and in vivo. Nonsurgical correction of cartilage deformities and malformations often uses mechanical stimuli and further demonstrates the plasticity of cartilage shape. Cartilage shape plasticity appears to diminish with maturation, coincident with changes in matrix composition. This study's objectives were to characterize shape plasticity of articular cartilage from immature and mature bovines and test whether altering proteoglycan and collagen (COL) remodeling modulates shape plasticity in vitro. Cartilage explants were analyzed fresh on day 0 or after 14 days of culture in the presence of β-D-xyloside to suppress glycosaminoglycan accumulation or β-aminopropionitrile (BAPN) to inhibit lysyl oxidase-mediated COL crosslinking. Culture with β-d-xyloside and BAPN differentially regulated cartilage size, composition, and shape plasticity, with an inverse association between shape plasticity and the ratio of tissue COL to glycosaminoglycan. Retention of a mechanically imposed contour was increased by culture with BAPN compared to day 0 calf cartilage (90% vs. 69%), and BAPN-treated samples had higher shape retention than β-D-xyloside-treated samples for both calf (90% vs. 74%) and adult cartilage (54% vs. 31%). The findings provide quantitative measures of cartilage shape plasticity at immature and mature stages and are consistent with the concept of diminishing shape plasticity with maturation. The ability to modulate cartilage shape plasticity by varying in vitro biochemical conditions may be a useful tool for the formation of contoured chondral grafts.

The present research examined music preferences in relation to the seasons: fall, winter, spring, and summer. Across two studies, male and female college students (N = 232 and 199) were primed to think about the seasons and indicate their music preference from Rentfrow and Gosling’s (2003) music classification scheme. Participants were predicted to prefer reflexive and complex music when primed with fall/winter and energetic and rhythmic and upbeat and conventional music when primed with spring/summer. Study 1 had participants read winter or summer season scenarios and Study 2 had participants write their own fall, winter, spring, or summer seasonal experiences. Overall, results were consistent with predictions for the reflexive and complex and energetic and rhythmic classifications, indicating an environmental influence of musical preferences.

Standard surveillance traps in North America for adult Aedes albopictus (Skuse) (Diptera: Culicidae), an invasive mosquito with public health implications, are currently ineffective. We compared the efficacy of the BG-Sentinel trap (BGS) with and without lures (BG-lure, octenol, and CO2), the Centers for Disease Control and Prevention light trap (CDC) with and without lures, and the gravid trap (GT) for Ae. albopictus collection in two urban sites in New Jersey. The BGS with or without lures collected more Ae. albopictus compared with other trap configurations and was more specific for Ae. albopictus. In Camden County, the BGS with lures collected three times more Ae. albopictus than the CDC (with CO2 only) and five times more than the GT. In Mercer County, BGS with lures collected the most mosquitoes, with 3 times more Ae. albopictus than the CDC with all lures and 50 times more than the GT. The BGS collected more male Ae. albopictus than other traps in both counties, providing further population monitoring. The GT and BGS provided a relative measure of the enzootic activity of West Nile virus in Culex spp. and the potential epidemic activity of WNV in Ae. albopictus. The BGS provides effective chemical and visual cues for host-seeking Ae. albopictus and should be used as a part of existing surveillance programs and new initiatives targeting this mosquito.

Flexural deformation has been used for the biomechanical characterization of native and engineered cartilage and as a mechanical stimulus to induce alteration of cartilage shape during in vitro culture. Flexure is also a physiologically relevant mode of deformation for various cartilaginous structures such as the ears and nose, but a kinematic description of cartilage in flexure is lacking even for simple deformations. The hypothesis of this study was that tension-compression (T-C) nonlinearity of cartilage will result in asymmetrical strain distributions during bending, while a material with similar behavior in tension and compression, such as alginate, will have a more symmetrical distribution of strains. Strips of calf articular cartilage and alginate were tested under uniform circular bending, and strains were determined by a micromechanical analysis of images acquired by epifluorescence microscopy. This experimental analysis was interpreted in the context of a model of small-deflection, pure bending of thin, homogeneous beams of a bimodular elastic material. The results supported the hypothesis and showed that marked asymmetry existed in cartilage flexural strains where the location of the neutral axis was significantly different than the midline and closer to the tensile surface. In contrast, alginate samples had a centrally located neutral axis. These experimental results were supported by the model indicating that the bimodular simplification of cartilage properties is a useful first approximation of T-C nonlinearity in these tests. The neutral axis location in cartilage samples was not influenced by the testing orientation (towards or away from the superficial-most tissue) or magnitude of flexure. These findings characterize the kinematics of cartilage at equilibrium during simple bending and indicate that T-C nonlinearity is an important determinant of the flexural strain distributions in the tested tissue.

Shaped cartilage grafts can be used in the restoration of injured joints and the reconstruction of deformities of the head and neck. This study describes a novel method for altering cartilage shape, based on the hypothesis that mechanical loading coupled with in vitro tissue growth and remodeling facilitates tissue reshaping. Static bending deformations were imposed on strips of immature articular cartilage, and retention of the imposed shape and structural and biochemical measures of growth were assessed after 2, 4, and 6 days of incubation. The results show that mechanical reshaping of tissue is feasible, because shape retention was greater than 86% after 6 days of culture. The imposed mechanical deformations had little effect on measures of tissue viability or growth within the 6-day culture period. The addition of cycloheximide to the culture medium only slightly reduced the ability to reshape these tissues, but cycloheximide plus a lower culture temperature of 4 degrees C markedly inhibited the reshaping response. These results suggest a limited role for chondrocyte biosynthesis but a potentially important role for metabolic reactions in the cartilage matrix in the reshaping process. The ability to modulate cartilage shape in vitro may prove useful for tissue engineering of shaped cartilage grafts.

We performed longitudinal surveys of mosquito larval abundance (mean mosquito larvae per dip) in 87 stormwater ponds and constructed wetlands in Delaware from June to September 2004. We analyzed selected water quality factors, water depth, types of vegetation, degree of shade, and level of insect predation in relation to mosquito abundance. The 2004 season was atypical, with most ponds remaining wet for the entire summer. In terms of West Nile virus (WNV) vectors, wetlands predominantly produced Aedes vexans, Culex pipiens pipiens, and Culex restuans. Retention ponds generally produced the same species as wetlands, except that Cx. p. pipiens was more abundant than Cx. restuans in retention ponds. Aedes vexans and Culex salinarius were the most abundant species in Conservation Restoration Enhancement Program ponds. Sand filters uniquely produced high numbers of Cx. restuans, Cx. p. pipiens, and Aedes japonicus japonicus, a newly invasive vector species. Sites that alternately dried and flooded, mostly detention ponds, forebays of retention ponds, and some wetlands often produced Ae. vexans, an occasional WNV bridge vector species. Overall, seasonal distribution of vectors was bimodal, with peaks occurring during early and late summer. Ponds with shallow sides and heavy shade generally produced an abundance of mosquitoes, unless insect predators were abundant. Bright, sunny ponds with steep sides and little vegetation generally produced the fewest mosquitoes. The associations among mosquito species and selected vegetation types are discussed.

Chondrocyte density in articular cartilage is known to change with the development and growth of the tissue and may play an important role in the formation of a functional extracellular matrix (ECM). The objective of this study was to determine how initial chondrocyte density in an alginate hydrogel affects the matrix composition, its distribution between the cell-associated (CM) and further removed matrix (FRM) fractions, and the tensile mechanical properties of the developing engineered cartilage. Alginate constructs containing primary bovine chondrocytes at densities of 0, 4, 16, and 64 million cells/ml were fabricated and cultured for 1 or 2 weeks, at which time structural, biochemical, and mechanical properties were analyzed. Both matrix content and distribution varied with the initial cell density. Increasing cell density resulted in an increasing content of collagen and sulfated-glycosaminoglycan (GAG) and an increasing proportion of these molecules localized in the CM. While the equilibrium tensile modulus of cell-free alginate did not change with time in culture, the constructs with highest cell density were 116% stiffer than cell-free controls after 2 weeks of culture. The equilibrium tensile modulus was positively correlated with total collagen (r2 = 0.47, p < 0.001) and GAG content (r2 = 0.68, p < 0.001), and these relationships were enhanced when analyzing only those matrix molecules in the CM fraction (r2 = 0.60 and 0.72 for collagen and GAG, respectively, each p < 0.001). Overall, the results of this study indicate that initial cell density has a considerable effect on the developing composition, structure, and function of alginate–chondrocyte constructs.

This study compared an integrated pest management (IPM) program with conventional, calendar-based pest control in nine North Carolina elementary schools. Both programs primarily targeted the German cockroach, Blattella germanica (L.). The IPM program relied heavily on monitoring and baiting, whereas the conventional approach used baseboard and crack-and-crevice sprays of insecticides. Within the constraints of an existing pest management contract, we quantified service duration, materials used, cost, levels of cockroach infestation, and the pesticide residues generated by the two service types. IPM services were significantly more time-consuming than conventional services, resulting in a significantly higher cost associated with labor. Nevertheless, the two types of treatments incurred similar total costs, and the efficacy of both treatments was also similar. Most importantly, pest monitoring, a central element of the IPM program, revealed few cockroaches and indicated that most of the conventional treatments were unnecessary. Environmental residues of the organophosphate pesticides acephate, chlorpyrifos, and propetamphos were significantly higher in swab samples taken in the conventionally treated schools. This study demonstrates that an IPM program is an appropriate and preferable alternative to conventional methods of pest control in the school environment.

Paucity of data on host-feeding patterns and behavior of 43 mosquito species that are reported as suspected West Nile virus (WN) vectors has limited full evaluation of their vectorial capacity. Recent studies addressing this issue need additional confirmation and should also be expanded to include collections of species or subpopulations attracted to humans. We used 4 types of collection methods to collect mosquitoes, including omnidirectional Fay-Prince traps, Centers for Disease Control-type light traps, gravid traps, and human-landing collections. Mosquitoes were collected during 2 full WN transmission seasons in 2001 and 2002, at 9 different sites across Delaware. We collected from various habitats, including salt marshes, brackish water areas, woodlands, a tire dump, a racetrack, and a mushroom farm. Blood-meal analyses were performed on parous mosquitoes by using a sandwich-type enzyme-linked immunosorbent assay. We tested primarily for 5 common host species, including rabbits, dogs, deer, horses, and chickens. We obtained substantial host-feeding data from 8 mosquito species. The most mammalophilic species were Anopheles quadrimaculatus, Coquillettidia perturbans, and Aedes albopictus, whereas the most ornithophilic species was Culex pipiens. Aedes albopictus was the most anthropophilic species, whereas Ae. vexans and Cq. perturbans exhibited relatively low attraction to humans. Culex salinarius was the species with the most diverse host-feeding activity. Based on feeding behavior, Cx. pipiens and Cx. salinarius appear to be the most likely bridge vectors. Other species may have opportunities to be bridge vectors under special circumstances, as discussed in the paper.

The pericellular matrix (PCM) is a narrow region of cartilaginous tissue that surrounds chondrocytes in articular cartilage. Previous modeling studies indicate that the mechanical properties of the PCM relative to those of the extracellular matrix (ECM) can significantly affect the stress-strain, fluid flow, and physicochemical environments of the chondrocyte, suggesting that the PCM plays a biomechanical role in articular cartilage. The goals of this study were to measure the mechanical properties of the PCM using micropipette aspiration coupled with a linear biphasic finite element model, and to determine the alterations in the mechanical properties of the PCM with osteoarthritis (OA). Using a recently developed isolation technique, chondrons (the chondrocyte and its PCM) were mechanically extracted from non-degenerate and osteoarthritic human cartilage. The transient mechanical behavior of the PCM was well-described by a biphasic model, suggesting that the viscoelastic response of the PCM is attributable to flow-dependent effects, similar to that of the ECM. With OA, the mean Young's modulus of the PCM was significantly decreased (38.7+/-16.2 kPa vs. 23.5+/-12.9 kPa, p0.001), and the permeability was significantly elevated (4.19+/-3.78 x10(-17) m(4)/Ns vs. 10.2+/-9.38 x 10(-17) m(4)/Ns, p0.01). The Poisson's ratio was similar for both non-degenerate and OA PCM (0.044+/-0.063 vs. 0.030+/-0.068, p0.6). These findings suggest that the PCM may undergo degenerative processes with OA, similar to those occurring in the ECM. In combination with previous theoretical models of cell-matrix interactions in cartilage, our findings suggest that changes in the properties of the PCM with OA may have an important influence on the biomechanical environment of the chondrocyte.

We evaluated 2 strategies to manage Aedes albopictus: 1) motorized backpack applications and 2) source reduction (coupled with hand-applied applications of larvicide). Backpack applications used a water-dispersible granular formulation (VectoBac WDG) of Bacillus thuringiensis var. israelensis (Bti), whereas source reduction used granular formulations of the insect growth regulator methoprene (Altosid) combined with a monomolecular film surfactant (Agnique). Six subplots (total 8.02 ha) were selected for backpack applications, source reduction, and control groups. The experiments were blind with applications conducted randomly and independently. Efficacy was determined through placement of bioassay cups with larvae within experimental plots 1 day before treatment. Backpack applications resulted in 76% (+/- 8.2% SE) and source reduction resulted in 92% (+/- 4.1% SE) larval mortality. Backpack applications required 50 times less labor than source reduction (0.25 versus 0.005 ha/h). The cost of backpack applications, including labor, was $159.88/ha, compared with $659.65/ha for source reduction. Although overall efficacy was slightly lower, motorized backpack applications of Bti were more efficient and cost-effective than source reduction methods to control Ae. albopictus in urban settings at the community level.

The bacterial agent Bacillus thuringiensis israelensis (Bti) is a highly effective larvicide against various medically important mosquito and black fly vector species. Recent formulations of this powerful larvicidal tool have been evaluated for their field efficacy in integrated mosquito management programs. Laboratory and controlled-condition trials have indicated long periods of residual efficacy, whereas field persistence is often much lower in duration. We investigated the residual persistence of high doses of 2 formulations of Bti, a water-dispersible granule (VectoBac® WDG; 16 mg/liter) and an extruded pellet (VBC-60066; 80 mg/liter), for the management of natural larval populations of Aedes albopictus. Laboratory tests demonstrated 100% (WDG) and ≥99.7% (VBC) average mortality across all treatments over 180 days. Field tests exhibited 100% efficacy (WDG and VBC) for 3 wk against Ae. albopictus and other coinhabiting mosquito species, with some residual efficacy lasting for >4 wk. These results are discussed in relation to current field control of domestic Aedes vectors of public health significance.

The increasing range of Aedes albopictus, the Asian tiger mosquito, in the USA and the threat of chikungunya and dengue outbreaks vectored by this species have necessitated novel approaches to control this peridomestic mosquito. Conventional methods such as adulticiding provide temporary relief, but fail to manage this pest on a sustained basis. We explored the use of cold aerosol foggers and misting machines for area-wide applications of Bacillus thuringiensis var. israelensis (VectoBac WDG) as a larvicide targeting Aedes albopictus. During 2010–2013 we performed initially open field trials and then 19 operational area-wide applications in urban and suburban residential areas in northeastern USA to test three truck-mounted sprayers at two application rates. Area-wide applications of WDG in open field conditions at 400 and 800 g/ha killed on average 87% of tested larvae. Once techniques were optimized in residential areas, applications with a Buffalo Turbine Mist Sprayer at a rate of 800 g/ha, the best combination, consistently provided over 90% mortality. Importantly, there was no significant decrease in efficacy with distance from the spray line even in blocks of row homes with trees and bushes in the backyards. Under laboratory conditions Bti deposition in bioassay cups during the operational trials resulted in over 6 weeks of residual control. Our results demonstrate that area-wide truck mounted applications of WDG can effectively suppress Ae. albopictus larvae and should be used in integrated mosquito management approaches to control this nuisance pest and disease vector.

We conducted an open-field ultra-low volume efficacy bioassay using a water-based formulation AquaDuet (prallethrin [1%], sumithrin [5%], and piperonly butoxide [5%]) applied from a truck-mounted cold aerosol sprayer. The adulticide was applied at 90.6 ml/ha (1.23 oz/acre) and 3 replicated treatments were performed using caged Aedes albopictus collected from local wild populations. Rotating impingers and mosquito cages were placed in 3 rows stationed at 30.5 m (100 ft), 61.0 (200 ft), and 91.4 (300 ft) downwind of the spray vehicle. Initial knockdown was 95.6%, with overall mortality99% across all distances, despite low wind conditions. Volume median diameter (Dv0.5) and droplet density were 17.4 microm and 110.5 mm2, respectively. Our open-field studies against caged Ae. albopictus demonstrate that a water-based adulticide formulation is just as efficacious as traditional oil-based formulations.

Rat posterolateral lumbar fusion (PLF) models have been used to assess the safety and effectiveness of new bone substitutes and osteoinductive growth factors using palpation, radiography, micro-computed tomography (μCT), and histology as standard methods to evaluate spinal fusion. Despite increased numbers of PLF studies involving alternative bone substitutes and growth factors, the quantitative assessment of treatment efficacy during spinal motion has been limited. The purpose of this study was to evaluate the effect of spinal fusion on lumbar spine segment stability during lateral bending using a μCT-based three-dimensional (3D) kinematic analysis in the rat PLF model. Fourteen athymic male rats underwent PLF surgery at L4/5 and received bone grafts harvested from the ilium and femurs of syngeneic rats (Isograft, n=7) or no graft (Sham, n=7). At 8 weeks after the PLF surgery, spinal fusion was assessed by manual palpation, plain radiography, μCT, and histology. To determine lumbar segmental motions at the operated level during lateral bending, 3D kinematic analysis was performed. The Isograft group, but not the Sham group, showed spinal fusion on manual palpation (6/7), solid fusion mass in radiographs (6/7), as well as bone bridging in μCT and histological images (5/7). Compared to the Sham group, the Isograft group revealed limited 3D lateral bending angular range of motion and lateral translation during lateral bending at the fused segment where disc height narrowing was observed. This μCT-based 3D kinematic analysis can provide a quantitative assessment of spinal fusion in a rat PLF model to complement current gold standard methods used for efficacy assessment of new therapeutic approaches.

In Saccharomyces cerevisiae, Msh2-Msh3-mediated mismatch repair (MMR) recognizes and targets insertion/deletion loops for repair. Msh2-Msh3 is also required for 3′ non-homologous tail removal (3′NHTR) in double-strand break repair. In both pathways, Msh2-Msh3 binds double-strand/single-strand junctions and initiates repair in an ATP-dependent manner. However, we recently demonstrated that the two pathways have distinct requirements with respect to Msh2-Msh3 activities. We identified a set of aromatic residues in the nucleotide binding pocket (FLY motif) of Msh3 that, when mutated, disrupted MMR, but left 3′ NHTR largely intact. One of these mutations, msh3Y942A, was predicted to disrupt the nucleotide sandwich and allow altered positioning of ATP within the pocket. To develop a mechanistic understanding of the differential requirements for ATP binding and/or hydrolysis in the two pathways, we characterized Msh2-Msh3 and Msh2-msh3Y942A ATP binding and hydrolysis activities in the presence of MMR and 3′ NHTR DNA substrates. We observed distinct, substrate-dependent ATP hydrolysis and nucleotide turnover by Msh2-Msh3, indicating that the MMR and 3′ NHTR DNA substrates differentially modify the ATP binding/hydrolysis activities of Msh2-Msh3. Msh2-msh3Y942A retained the ability to bind DNA and ATP but exhibited altered ATP hydrolysis and nucleotide turnover. We propose that both ATP and structure-specific repair substrates cooperate to direct Msh2-Msh3-mediated repair and suggest an explanation for the msh3Y942A separation-of-function phenotype.