Field Longevity of a Fluorescent Protein Marker in an Engineered Strain of the Pink Bollworm, Pectinophora gossypiella (Saunders)

The cotton pest, pink bollworm (Pectinophora gossypiella (Saunders)), is a significant pest in most cotton-growing areas around the world. In southwestern USA and northern Mexico, pink bollworm is the target of the sterile insect technique (SIT), which relies on the mass-release of sterile pink bollworm adults to over-flood the wild population and thereby reduce it over time. Sterile moths reared for release are currently marked with a dye provided in their larval diet. There are concerns, however, that this marker fails from time to time, leading to sterile moths being misidentified in monitoring traps as wild moths. This can lead to expensive reactionary releases of sterile moths. We have developed a genetically marked strain that is engineered to express a fluorescent protein, DsRed2, which is easily screened under a specialised microscope. In order to test this marker under field conditions, we placed wild-type and genetically marked moths on traps and placed them in field cages. The moths were then screened, in a double-blind fashion, for DsRed2 fluorescence at regular intervals to determine marker reliability over time. The marker was shown to be robust in very high temperatures and generally proved reliable for a week or longer. More importantly, genotyping of moths on traps by PCR screening of the moths was 100% correct. Our findings indicate that this strain - and fluorescent protein markers in general - could make a valuable contribution to SIT

Efficient control of atmospheric sulfate production based on three formation regimes

The formation of sulfate (SO₄²⁻) in the atmosphere is linked chemically to its direct precursor, sulfur dioxide (SO₂), through several key oxidation paths for which nitrogen oxides or NO_x (NO and NO₂) play essential roles. Here we present a coherent description of the dependence of SO₄²⁻ formation on SO₂ and NO_x under haze-fog conditions, in which fog events are accompanied by high aerosol loadings and fog-water pH in the range of 4.7–6.9. Three SO₄²⁻ formation regimes emerge as defined by the role played by NO_x. In the low-NO_x regime, NO_x act as catalyst for HO_x, which is a major oxidant for SO₂, whereas in the high-NO_x regime, NO₂ is a sink for HO_x. Moreover, at highly elevated NO_x levels, a so-called NO₂-oxidant regime exists in which aqueous NO₂ serves as the dominant oxidant of SO₂. This regime also exists under clean fog conditions but is less prominent. Sensitivity calculations using an emission-driven box model show that the reduction of SO₄²⁻ is comparably sensitive to the reduction of SO₂ and NO_x emissions in the NO₂-oxidant regime, suggesting a co-reduction strategy. Formation of SO₄²⁻ is relatively insensitive to NO_x reduction in the low-NO_x regime, whereas reduction of NO_x actually leads to increased SO₄²⁻ production in the intermediate high-NO_x regime

Does transcranial direct current stimulation to prefrontal cortex affect mood and emotional memory retrieval in healthy individuals?

Studies using transcranial direct current stimulation (tDCS) of prefrontal cortex to improve symptoms of depression have had mixed results. We examined whether using tDCS to change the balance of activity between left and right dorsolateral prefrontal cortex (DLPFC) can alter mood and memory retrieval of emotional material in healthy volunteers. Participants memorised emotional images, then tDCS was applied bilaterally to DLPFC while they performed a stimulus-response compatibility task. Participants were then presented with a set of images for memory retrieval. Questionnaires to examine mood and motivational state were administered at the beginning and end of each session. Exploratory data analyses showed that the polarity of tDCS to DLPFC influenced performance on a stimulus-response compatibility task and this effect was dependent on participants' prior motivational state. However, tDCS polarity had no effect on the speed or accuracy of memory retrieval of emotional images and did not influence positive or negative affect. These findings suggest that the balance of activity between left and right DLPFC does not play a critical role in the mood state of healthy individuals. We suggest that the efficacy of prefrontal tDCS depends on the initial activation state of neurons and future work should take this into account. © 2014 Morgan et al

Paradoxical emboli in children and young adults: role of atrial septal defect and patent foramen ovale device closure

Abstract OBJECTIVE: To describe a multicenter experience with patent foramen ovale (PFO) and atrial septal defect (ASD) device closure for presumed paradoxical emboli in children and young adults (<35 years old). PATIENTS AND METHODS: Medical records were reviewed of patients who had device closure of an ASD or PFO, who were younger than 35 years, and who had a history of presumed paradoxical embolus between January 1999 and August 2005 at Mayo Clinic, Rochester, Minn, University of Parma, Parma, Italy, and Loyola University Medical Center, Maywood, Ill. RESULTS: Forty-five patients fulfilled the inclusion criteria. Median patient age was 29.0 years (range, 5.0-34.9 years), and 23 patients (51%) were male. Clinical diagnoses included the following: stroke, 30 (67%); transient ischemic attack, 13 (29%); myocardial infarction, 1 (2%); and renal infarct, 1 (2%). Overall, 42 patients (93%) had a PFO, and 3 (7%) had an ASD. Seventeen patients had known cardiovascular disease risk factors: tobacco use (10 patients), hypercoagulable states (7 patients), systemic hypertension (3 patients), and hyperilpidemia (2 patients). No major procedural complications occurred. Median follow-up evaluation was performed at 5.3 months (range, 2.5-40.0 months). Forty-four patients (98%) had no recurrent neurologic events and no residual atrial shunt by contrast transthoracic echocardiography. CONCLUSIONS: Cryptogenic ischemic events occur in young patients and have serious sequelae. The potential for paradoxical embolization through a PFO or an ASD should be assessed in all such patients. In our short-term follow-up, device closure was a safe alternative therapeutic option for children and young adults with presumed paradoxical emboli