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We studied the effect of iron addition on particle export in the Southern Ocean by measuring changes in the distribution of thorium-234 during a 4-week iron (Fe) enrichment experiment conducted in the high-silicate high-nitrate waters just south of the Southern Antarctic Circumpolar Current Front at 172.5°W. Decreases in ^{234}\\text{Th}$ activity with time in the fertilized mixed layer (0-50 m) exceeded those in unfertilized waters, indicating enhanced export of ^{234}\\text{Th}$ on sinking particles after Fe enrichment. The addition of Fe also affected export below the fertilized patch by increasing the efficiency of particle export through the 100-m depth horizon. Extensive temporal and vertical Lagrangian sampling allowed us to make a detailed examination of the ^{234}\\text{Th}$ flux model, which was used to quantify the fluxes of particulate organic carbon (POC) and biogenic silica ($\\text{bSiO}_{2}$). Iron addition increased the flux of both POC and $\\text{bSiO}_{2}$ out of the mixed layer by about 300%. The flux at 100 m increased by more than 700% and 600% for POC and $\\text{bSiO}_{2}$, respectively. The absolute magnitude of the POC and $\\text{bSiO}_{2}$ fluxes were not large relative to natural blooms at these latitudes or to those found in association with the termination of blooms in other ocean regions. Our results support the hypothesis that Fe addition leads directly to significant particle export and sequestration of C in the deep ocean. This is a key link between ocean Fe inputs and past changes in atmospheric CO2 and climate.

Modified, agricultural landscapes are susceptible to damage by insect pests. Biological control of pests is typically successful once a control agent has established, but this depends on the agent’s capacity to co-evolve with the host. Theoretical studies have shown that different levels of genetic variation between the host and the control agent will lead to rapid evolution of resistance in the host. Although this has been reported in one instance, the underlying genetics have not been studied. To address this, we measured the genetic variation in New Zealand populations of the pasture pest, Argentine stem weevil (Listronotus bonariensis), which is controlled with declining effectiveness by a parasitoid wasp, Microctonus hyperodae. We constructed a draft reference genome of the weevil, collected samples from a geographical survey of 10 sites around New Zealand, and genotyped them using a modified genotyping-by-sequencing approach. New Zealand populations of Argentine stem weevil have high levels of heterozygosity and low population structure, consistent with a large effective population size and frequent gene flow. This implies that Argentine stem weevils were able to evolve more rapidly than their biocontrol agent, which reproduces asexually. These findings show that monitoring genetic diversity in biocontrol agents and their targets is critical for long-term success of biological control.

Contributions by L.J.N. and E.G.B. were supported by the New Zealand government via Ministry of Business, Innovation, and Employment core funding to Plant and Food Research and Scion (contract C04X1104), respectively, and the BetterBorder Biosecurity Collaboration (www.b3nz.org).

The egg, larval, pupal and adult abundance of the clover root weevil Sitona lepidus Gyllenhal (Coleoptera: Curculionidae) was monitored at three sites for the first ten years following the discovery of this exotic pest in the Waikato region of New Zealand. The species went through an initial boom and bust cycle at two sites, with populations reaching up to 1800 larvae m−2. Thereafter, winter larval populations were relatively stable, ranging between 450–750 m−2. Unlike in the Northern Hemisphere, S. lepidus was found to have two generations a year in the Waikato region of New Zealand. Pasture white clover content at the time of peak adult numbers was positively related to the subsequent peak larval populations for each generation. The factors contributing to the emergence of S. lepidus as one of the most important pasture pests in New Zealand are discussed.

This study investigates the presence of sensory modulation dysfunction (SMD) among children with attention‐deficit‐hyperactivity disorder (ADHD). Twenty‐six children with ADHD (mean age 8.3 years, 18 males, 8 females), and 30 typically developing children (mean age 8.2 years, 21 males, 9 females) were tested using a laboratory procedure that gauges responses to repeated sensory stimulation by measuring electrodermal reactivity (EDR). Parental report measures of limitations in sensory, emotional, and attentional dimensions were administered using the Short Sensory Profile, the Leiter International Performance Scale‐Revised, Parent Rating subscales, and the Child Behavior Checklist (CBCL). Compared to the typical sample, the children with ADHD displayed greater abnormalities in sensory modulation on both physiological and parent‐report measures. The children with ADHD also displayed more variability in responses. Within the group with ADHD, levels of SMD were highly correlated with measures of psychopathology on the CBCL. Implications of findings relate to the importance of considering sensory processing abilities in a subgroup of children with ADHD.

This study investigates the presence of sensory modulation dysfunction (SMD) among children with attention-deficit-hyperactivity disorder (ADHD). Twenty-six children with ADHD (mean age 8.3 years, 18 males, 8 females), and 30 typically developing children (mean age 8.2 years, 21 males, 9 females) were tested using a laboratory procedure that gauges responses to repeated sensory stimulation by measuring electrodermal reactivity (EDR). Parental report measures of limitations in sensory, emotional, and attentional dimensions were administered using the Short Sensory Profile, the Leiter International Performance Scale–Revised, Parent Rating subscales, and the Child Behavior Checklist (CBCL). Compared to the typical sample, the children with ADHD displayed greater abnormalities in sensory modulation on both physiological and parent-report measures. The children with ADHD also displayed more variability in responses. Within the group with ADHD, levels of SMD were highly correlated with measures of psychopathology on the CBCL. Implications of findings relate to the importance of considering sensory processing abilities in a subgroup of children with ADHD.

A pacemaker-bearing patient with left-sided breast cancer was treated with adjuvant external beam radiation therapy to the intact breast. She was treated via tangential fields and a single anterior supraclavicular field using 6-MV x-rays. The pacemaker, originally in the treatment field, was removed and a new one placed 4 cm outside the radiation field prior to treatment. Silicon diode chamber Keithley-Farmer type 0.6 cc ionization chamber, and lithium fluoride (LiF) (TLD) chips were used to measure, in vivo, the dose to the pacemaker. From all the fields treated, total dose to the pacemaker was 164 cGy by diode measurements, 182 cGy by ionization chamber measurements, and 171 cGy by TLD measurements. The pacemaker functioned normally throughout the course of treatment.

To evaluate the patterns of failure, relapse-free survival and overall survival among African American breast cancer patients younger than 40 years. We retrospectively reviewed the records of 124 African American breast cancer patients younger than 40 years who were registered with the Howard University Cancer Center Database between 1990 and 1999. One hundred and six patients were found eligible and subsequently included in this analysis. Ninety-eight percent of these patients were pre-menopausal and 30% had a documented family history of breast cancer. Patient distribution per stage is as follows: 19%, stage I; 61%, stage II; 16%, stage III and 4%, stage IV. Surgery was a component of treatment for 98% of the patients. Forty-six percent underwent mastectomy, 47% had breast-conserving surgery and 5% underwent biopsy only. Fifty-nine percent of the patients received adjuvant radiation and 56% were also treated with adjuvant chemotherapy. Median follow-up was 35 months (range of 4-126 months). Locoregional only first failure rate was 6% while systemic failure occurred in 20% of these patients. Among 17 stage III patients, 50% developed distant metastasis. The 5-year overall survival for these patients was 73%, with relapse-free survival being numerically similar. Patients with early stage disease, stages I and II, were noted to have 5-year overall survival rates of 100 and 78-83%, respectively. Those who presented with stage III or stage IV disease had dismal 5-year overall survival rates of 25-29 and 0%, respectively. Multivariate analysis using the Cox proportional hazard model identified the presence of metastasis as a factor that significantly affects survival in these young African American females. These results show that African American females younger than 40 years with early stage breast cancer have local control and survival rates comparable to that of the general population. In contrast, young African American females in this study, with stages III and IV disease, appear to suffer a worse prognosis despite standard therapy. A larger series of young African American females with breast cancer, followed for a longer period of time, will be required to confirm a negative trend in survival.

Despite an increase in the awareness of autism, families and professionals continue to struggle to find treatments that will fulfil the individual needs of their child. From Research to Individualized Practice bridges the gap between the latest research findings and clinical practice. The authors have brought together information from both fields in order to offer the reader best practice principles and hands-on techniques. These are all exemplified by clinical case examples and vivid illustrations.

(1) Sitona discoideus Gyllenhal population data collected from young lucerne (Medicago sativa L.) in Canterbury, New Zealand in 1982-86 were analysed using life tables. Manipulated weevil densities in 1983-84 allowed intra-seasonal and inter-seasonal relationships to be studied. (2) In general, there was a high degree of density-dependent mortality, probably amongst the neonate larvae during their establishment in the root nodules. (3) There was considerable variation in the pattern of larval survival in wet compared with dry seasons. In the latter, density-dependent effects occurred after little cumulative egg laying (750-2400 eggs m-2) compared with higher levels (11 770 m-2) in the wet season. Under wet conditions, there was greater mortality amongst the later instars. (4) Egg laying in the field was modelled on laboratory-derived temperature/rate relationships and field air temperatures. Model predictions suggested that 30-50% of the maximum fecundity was reached, indicating some maladaptation. (5) The range of feeding habits of Sitona spp. is reviewed with regard to the degree of dependence of the genus on root nodules.