Understanding cues for diapause termination in insects can be valuable in predicting phenological events in their lifecycles. Once identified, such cues can be utilized as a biofix, the point at ...which the majority of individuals within a population begin to accumulate degree days. We investigated the impact of photoperiod on completion of reproductive diapause in the invasive eastern North American population of the brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), by exposing diapausing females to varying light regimes in otherwise identical environments. The critical photoperiod estimated to initiate reproductive development in at least 50% of the potential reproductive population was 13.0–13.5 h, with increasing photoperiods coinciding with increased probability of females reproducing, earlier time to first oviposition, and higher rates of fecundity. These data on the species' response to photoperiod are in agreement with previous modeling that predicted the twin constraints of photoperiod and temperature on H. halys reproduction prevents populations that undergo diapause from producing more than two generations annually anywhere within the continental U.S. However, the facultative nature of diapause in H. halys leaves open the possibility that sub-populations may not enter diapause in some conditions, potentially allowing for additional annual generations.
Brown marmorated stink bug,
(Stål) (Hemiptera: Pentatomidae), is a generalist pest that causes serious injury to a variety of crops around the world. After the first detection in the USA,
became a ...serious threat to growers resulting in significant crop damage. Understanding the effect of temperature on
development will help to achieve successful control by predicting the phenological timing of the pest. Here, life table parameters (survival, development, reproduction, and daily mortality) of
were evaluated for New Jersey and Oregon populations in the US. Parameters were determined from field-collected and laboratory-reared individuals. The results indicated that New Jersey populations had higher levels of egg-laying than Oregon populations and exhibited higher and earlier fecundity peaks. Survival levels were similar between populations. Linear and nonlinear fit were used to estimate the minimum (14.3 °C), optimal (27.8 °C), and maximum (35.9 °C) temperatures where development of
can take place. An age-specific fecundity peak (M
= 36.63) was recorded at 936 degree days for New Jersey populations, while maximum fecundity (M
= 11.85) occurred at 1145 degree days in Oregon. No oviposition was recorded at the lowest (15 °C) or highest (35 °C) trialed temperatures. Developmental periods increased at temperatures above 30 °C, indicating that such higher temperatures are suboptimal for
development. Altogether the most optimal temperatures for population increase (
) ranged from 25 to 30 °C. Survival rates of
at suboptimal low temperatures of 8 °C (i.e., 61%) is comparable to previous reports. The present paper provides additional data and context from a range of experimental conditions and populations. Such temperature-related
life table parameters can be used to provide determine the risk to susceptible crops.
In this study we focus on the invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), which has a strong dispersal capacity and has had a significant impact on ...several cropping systems, including peach (Prunus persica (L.)). Management of H. halys has relied on intensive insecticide use, and thus a better understanding of its dispersal behavior may assist in developing improved management strategies. In order to investigate H. halys movement and distribution patterns within a peach orchard we applied ecologically safe, food protein markers to the trees along the orchard border (chicken egg albumin in the form of liquid egg whites) and to the trees within the orchard interior (bovine casein in the form of cow's milk). We used enzyme-linked immunosorbent assays (ELISA) to assess whether collected H. halys were "marked" with either of the two protein markers, revealing where in the orchard the bugs had visited. From the density data we determined that H. halys is a perimeter-driven pest in peaches, with a significantly higher density of bugs collected along the orchard border. Interestingly, this trend is primarily driven by the distribution of male bugs. The protein marking data revealed that a small proportion of male H. halys move equally between the orchard border and interior, while a small proportion of females move predominately to the border after visiting the interior. The verification of a strong edge-effect, although potentially sex-specific, implies that H. halys displays a dispersal behavior that may also be exploited for management, which may help growers more efficiently and more effectively manage H. halys.
Background: Patients with inflammatory bowel disease (IBD) and symptoms of irritable bowel syndrome (IBS) may be intolerant to fermentable carbohydrates (FODMAPs). The aim of this study was to test ...the feasibility of eliminating and subsequently reintroducing FODMAPs in patients with IBS symptoms as part of the IBD manifestation and to compare the severity of IBS symptoms and pain, bloating and quality of life (QoL). Methods: An eight-week randomised open-label FODMAP elimination with double-blinded, crossover provocations of FODMAP and placebo. Diet patients were on a low-FODMAP diet for eight weeks with blinded two-week provocations after two and six weeks. Questionnaires, blood and stool samples were collected. Results: Patient enrolment was challenging. Nineteen participants were included in the study. Eliminating low FODMAP for two weeks resulted in significant decreases in pain and bloating scores (p < 0.003), whereas there were no statistical differences in pain scores between diet patients and controls. Pain and bloating scores increased, returning to baseline levels after two weeks of double-blinded provocations with placebo, (p > 0.05). Conclusions: The results document the possibility of performing a randomised controlled study following the gold standard for testing food intolerance with blinding of the Low FODMAP diet. Recruitment of participants was challenging.
The purpose of this study was to examine whether staging with
F-FDG PET/CT better predicts survival in patients with recurrent head and neck squamous cell carcinoma (HNSCC) than chest x-ray (CXR) ...plus head and neck MRI or chest CT (CCT) plus head and neck MRI.
This was a prospective cohort study based on paired data. Consecutive patients with histologically verified HNSCC recurrence were enrolled from September 2013 to March 2016. All patients underwent CXR/MRI, CCT/MRI, and PET/CT on the same day and before biopsy. All imaging studies underwent masked interpretation by separate teams of experienced nuclear physicians or radiologists. Recurrent carcinomas were categorized as localized (equivalent to primary stages I-II), locally advanced (equivalent to primary stages III-IVB), or metastatic (equivalent to primary stage IVC). Discriminative abilities for each imaging strategy with respect to cancer-specific and stage-based survival were compared using Kaplan-Meier analysis, Cox proportional-hazards regression with the Harrell concordance index (C-index), and net reclassification improvement.
In total, 110 patients (90 men and 20 women; median age, 66 y; range, 40-87 y) were included. PET/CT significantly changed the assigned tumor stage when compared with imaging strategies based on CXR/MRI or CCT/MRI (
< 0.001 for both). Kaplan-Meier analysis of PET/CT-based staging showed progressively worsened prognosis with localized, locally advanced, or metastatic disease (log-rank test,
< 0.001), whereas CXR/MRI and CCT/MRI were unable to distinguish between these groups in terms of survival (log-rank test,
= 0.18 and
= 0.58, respectively). Overall discriminative ability in predicting cancer-specific mortality was significantly greater for PET/CT (C-index, 0.72) than for CXR/MRI (C-index, 0.55) (
= 0.001) and CCT/MRI (C-index, 0.55)(
< 0.001). The addition of PET/CT to either CXR/MRI or CCT/MRI was associated with a significantly positive net reclassification improvement (
< 0.001 for both).
Contrary to standard imaging strategies, PET/CT-based staging in recurrent HNSCC was able to significantly discriminate among the survival courses of patients with local, locally advanced, or metastatic disease and predict their respective survival probability.
Host plant use by nymphs and adults of the nonnative species Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) was investigated proximal to the location of its introduction, Allentown, PA. The ...seasonality of H. halys in the United States had not been thoroughly studied before this work. It is reported to have ≈300 host plants in its native range that could make control and identification of small populations difficult. Weekly beat samples were conducted beginning at petal fall (mid-April) in Pyrus spp. until the first frost (mid-October) from 2005 to 2007 on a variety of ornamental trees, shrubs, and agricultural crops. Egg masses were first observed on Paulownia tomentosa Thunb. the first week of June. In 2006 and 2007, Fraxinus americana L. was an important mid- and late season host for adults. Nymphal abundance differed seasonally. P. tomentosa supported high densities during the early season, whereas Viburnum opulus variety americanum Aiton was the preferred mid-season host, and Viburnum prunifolium L. and Rosa rugosa Thunb. had the highest densities of nymphs during the late season. Abundance of nymphs was strongly associated with maturing fruit or pods. All plants surveyed supported populations of H. halys, suggesting a large host range. In late August, a large adult population peak was observed (850–1,000 degree days DD), shortly after the DD accumulation for development to imaginal eclosion, supporting hypotheses that H. halys is likely univoltine in this region. Relative to native pentatomid species, H. halys was by far the predominant species collected in samples on ornamental and cultivated crops.
Aim
To compare total metabolic tumour volume (tMTV), calculated using two artificial intelligence (AI)‐based tools, with manual segmentation by specialists as the reference.
Methods
Forty‐eight ...consecutive Hodgkin lymphoma (HL) patients staged with 18F fluorodeoxyglucose positron emission tomography/computed tomography were included. The median age was 35 years (range: 7–75), 46% female. The tMTV was automatically measured using the AI‐based tools positron emission tomography assisted reporting system (PARS) (from Siemens) and RECOMIA (recomia.org) without any manual adjustments. A group of eight nuclear medicine specialists manually segmented lesions for tMTV calculations; each patient was independently segmented by two specialists.
Results
The median of the manual tMTV was 146 cm3 (interquartile range IQR: 79–568 cm3) and the median difference between two tMTV values segmented by different specialists for the same patient was 26 cm3 (IQR: 10–86 cm3). In 22 of the 48 patients, the manual tMTV value was closer to the RECOMIA tMTV value than to the manual tMTV value segmented by the second specialist. In 11 of the remaining 26 patients, the difference between the RECOMIA tMTV and the manual tMTV was small (<26 cm3, which was the median difference between two manual tMTV values from the same patient). The corresponding numbers for PARS were 18 and 10 patients, respectively.
Conclusion
The results of this study indicate that RECOMIA and Siemens PARS AI tools could be used without any major manual adjustments in 69% (33/48) and 58% (28/48) of HL patients, respectively. This demonstrates the feasibility of using AI tools to support physicians measuring tMTV for assessment of prognosis in clinical practice.
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