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1.
MethodsX ; 11: 102305, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37577164

ABSTRACT

We present the first published method to convert data obtained by the Pioneer Venus Large Probe Neutral Mass Spectrometer (LNMS) into units of mixing ratio (ppm) and volume percent (v%) against CO2 and N2, the dominant Venus atmospheric gases, including conversion to density (kg m-3). These unit conversions are key to unlocking the untapped potential of the data, which represents a significant challenge given the scant calibration data in the literature. Herein, we show that our data treatments and conversions yield mixing ratios and volume percent values for H2O, N2, and SO2 that are within error to those reported for the gas chromatograph (LGC) on the Pioneer Venus Large Probe (PVLP). For the noble gases, we developed strategies to correct for instrument biases by treating the data as a relative scale and using PVLP and Venera-based measurements as calibration points. Together, these methods, conversions, calibrations, and comparisons afford novel unit conversions for the LNMS data and yield unified measures for Venus' atmosphere from the LNMS and LGC on the PVLP.•Conversion into mixing ratio (ppm), volume percent (v%), and density (kg m-3).•Mixing ratios are expressed against CO2 and N2.•LNMS and LGC measurements on the PVLP are consistent.

2.
Space Sci Rev ; 219(1): 13, 2023.
Article in English | MEDLINE | ID: mdl-36785654

ABSTRACT

Here we examine how our knowledge of present day Venus can inform terrestrial exoplanetary science and how exoplanetary science can inform our study of Venus. In a superficial way the contrasts in knowledge appear stark. We have been looking at Venus for millennia and studying it via telescopic observations for centuries. Spacecraft observations began with Mariner 2 in 1962 when we confirmed that Venus was a hothouse planet, rather than the tropical paradise science fiction pictured. As long as our level of exploration and understanding of Venus remains far below that of Mars, major questions will endure. On the other hand, exoplanetary science has grown leaps and bounds since the discovery of Pegasus 51b in 1995, not too long after the golden years of Venus spacecraft missions came to an end with the Magellan Mission in 1994. Multi-million to billion dollar/euro exoplanet focused spacecraft missions such as JWST, and its successors will be flown in the coming decades. At the same time, excitement about Venus exploration is blooming again with a number of confirmed and proposed missions in the coming decades from India, Russia, Japan, the European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA). Here we review what is known and what we may discover tomorrow in complementary studies of Venus and its exoplanetary cousins.

3.
J Econ Entomol ; 114(5): 2076-2087, 2021 10 13.
Article in English | MEDLINE | ID: mdl-34260707

ABSTRACT

Since outbreaks were first detected in grain sorghum, Sorghum bicolor (L.) Moench (Cyperales: Poaceae), in 2013, sugarcane aphid, Melanaphis sacchari Zehntner has become a major annual pest in grain sorghum-producing regions of North America. Economic thresholds have been recommended for susceptible hybrids, but these recommendations may not be suitable for grain sorghum hybrids partially resistant to sugarcane aphid. The objectives were to evaluate the grain yield-aphid density relationship and field-based population growth rates of the aphid on sorghum hybrids susceptible and partially resistant to sugarcane aphid across multiple years, locations, and hybrids. These data verified previously established economic injury levels for susceptible hybrids. The observed maximum aphid density ranged from 6 to 451 aphids per leaf for resistant hybrids and from 67 to 1,025 for susceptible hybrids. Across 50 location-year combinations, the maximum aphid density observed on resistant hybrids decreased by 0-99%, compared to a susceptible hybrid at the same location (mean reduction = 80%). Doubling time for sugarcane aphid populations on partially resistant hybrids was up to 6.4-fold higher than on known susceptible hybrids. For 48 of the 50 location-years, yield loss attributable to sugarcane aphid was not detected on the partially resistant hybrids; therefore, an economic injury level was unable to be estimated. If an economic injury level exists for resistant hybrids, it is likely at an aphid population level that exceeds the levels experienced in this study. It remains prudent to monitor resistant hybrids for unusual leaf decay associated with aphid densities that exceed current economic injury levels used for susceptible hybrids.


Subject(s)
Aphids , Sorghum , Animals , Edible Grain , North America , Sorghum/genetics
4.
Geophys Res Lett ; 48(7): e2020GL091327, 2021 Apr 16.
Article in English | MEDLINE | ID: mdl-34219837

ABSTRACT

We present a re-examination of mass spectral data obtained from the Pioneer Venus Large Probe Neutral Mass Spectrometer. Our interpretations of differing trace chemical species are suggestive of redox disequilibria in Venus' middle clouds. Assignments to the data (at 51.3 km) include phosphine, hydrogen sulfide, nitrous acid, nitric acid, carbon monoxide, hydrochloric acid, hydrogen cyanide, ethane, and potentially ammonia, chlorous acid, and several tentative PxOy species. All parent ions were predicated upon assignment of corresponding fragmentation products, isotopologues, and atomic species. The data reveal parent ions at varying oxidation states, implying the presence of reducing power in the clouds, and illuminating the potential for chemistries yet to be discovered. When considering the hypothetical habitability of Venus' clouds, the assignments reveal a potential signature of anaerobic phosphorus metabolism (phosphine), an electron donor for anoxygenic photosynthesis (nitrite), and major constituents of the nitrogen cycle (nitrate, nitrite, ammonia, and N2).

5.
BJOG ; 127(7): 820-827, 2020 06.
Article in English | MEDLINE | ID: mdl-31943696

ABSTRACT

OBJECTIVE: The aim of this study was to establish rotational thromboelastometry (ROTEM® ) baseline parameters in labouring women at term gestation. The secondary aim was to compare these reference ranges with those from previous studies on labouring women and from the manufacturer. DESIGN: A prospective, observational study. SETTING: Tertiary referral hospital. PARTICIPANTS: Healthy women in labour. METHODS: Ethics approval was granted for an opt-out recruitment approach. ROTEM® testing was performed in labouring women at term gestation. Women with any condition affecting coagulation were excluded. ROTEM® Delta reference ranges were derived by calculating the 2.5% and 97.5% centiles for INTEM/EXTEM/FIBTEM parameters including amplitude at 5 minutes (A5), coagulation time (CT) and maximum clot firmness (MCF). MAIN OUTCOME MEASURES: ROTEM® parameters were measured in labouring women before delivery. The following tests were performed: FIBTEM, EXTEM and INTEM. RESULTS: One hundred and twenty-one women met the inclusion criteria, with a mean (± SD) age of 29.6 ± 5.4 years and median (interquartile range) gestation of 39.4 weeks (37.4-40.4 weeks). Seventy-five (62.0%) women were nulliparous and 71 (58.7%) delivered vaginally. The median and interquartile ranges for selected ROTEM® parameters were: FIBTEM A5, 21 mm (IQR 18-23 mm); EXTEM A5, 55 mm (52-58 mm); and EXTEM CT, 52 seconds (48-56 seconds). CONCLUSIONS: The FIBTEM/EXTEM/INTEM amplitudes were higher than the manufacturer's reference ranges for non-obstetric patients. The FIBTEM MCF upper and lower limits were higher and the EXTEM/INTEM CT was shorter and narrower in range. This study provides reference ranges for ROTEM® values in healthy labouring women at term gestation with uncomplicated pregnancies. TWEETABLE ABSTRACT: This is the first study to report on ROTEM® reference ranges with over 120 healthy labouring women of normal weight at term gestation.


Subject(s)
Labor, Obstetric/physiology , Prenatal Diagnosis/statistics & numerical data , Thrombelastography/statistics & numerical data , Adult , Female , Healthy Volunteers , Humans , Pregnancy , Prenatal Diagnosis/methods , Prospective Studies , Reference Values , Thrombelastography/methods
6.
Int J Obstet Anesth ; 41: 7-13, 2020 02.
Article in English | MEDLINE | ID: mdl-31831279

ABSTRACT

BACKGROUND: Rotational thromboelastometry (ROTEM®) is a point-of-care coagulation test. Reference ranges in non-labouring women have recently been established from a cohort of women presenting for elective caesarean delivery using the recommended minimum sample size of 120. This study aimed to present baseline parameters for labouring and non-labouring women and to compare the mean values of these ROTEM® parameters. METHODS: Ethical approval was granted for an opt-out recruitment approach for labouring women and written consent was obtained from non-labouring women (data published previously). ROTEM® testing was performed in these two cohorts at term gestation. Women with any condition affecting coagulation were excluded. ROTEM® Delta reference ranges were derived by calculating the 2.5 and 97.5 percentiles for INTEM/EXTEM/FIBTEM amplitude at 5 min (A5), coagulation time (CT), maximum clot firmness (MCF) and clot formation time (CFT). RESULTS: One hundred and twenty-one labouring and 132 non-labouring women met inclusion criteria. The mean values for selected ROTEM® parameters for labouring and non-labouring women respectively were: FIBTEM A5, 21.05 and 19.7 mm (P=0.008); EXTEM A5, 54.8 and 53.2 mm (P=0.025); and EXTEM CT, 52.2 and 53.7 s (P=0.049). Significant differences between the groups were observed in measures of clotting onset and clot firmness. CONCLUSIONS: We demonstrated a significant decrease in the mean time-to-clotting onset in labouring women compared with non-labouring women. Mean values for measures of clot firmness were greater in labouring women. In comparison to previously established ROTEM® baseline parameters for non-labouring women, this study provides evidence that there is greater hyper-coagulability in labouring women.


Subject(s)
Labor, Obstetric/blood , Point-of-Care Testing , Pregnancy/blood , Thrombelastography/methods , Adult , Female , Humans , Reference Values
7.
Br J Dermatol ; 183(3): 503-508, 2020 09.
Article in English | MEDLINE | ID: mdl-31853948

ABSTRACT

BACKGROUND: Lung transplant recipients are at high risk of skin cancer, but precise annual incidence rates of treated skin cancers per patient are unknown. OBJECTIVES: To perform a prospective assessment of the total burden of histologically confirmed squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) and associated factors in lung transplant recipients. METHODS: A population-based cohort of 125 Queensland lung transplant recipients aged 18 years and over, recruited between 2013 and 2015, were followed to the end of 2016. All underwent dermatological skin examinations at baseline and annually thereafter and patients self-reported all interim treated skin cancers, which were verified against pathology databases. Standard skin cancer risk factors were obtained via questionnaire, and details of medications were acquired from hospital records. RESULTS: During a median follow-up time of 1·7 years, 29 (23%) and 30 (24%) lung transplant recipients with a median duration of immunosuppression of 3·3 years developed SCC and BCC, respectively. The general population age-standardized incidence rates of SCC and BCC were 201 and 171 per 1000 person-years, respectively (based on first primary SCC or BCC during follow-up); however, on accounting for multiple primary tumours, corresponding incidence rates were 447 and 281 per 1000 person-years. Risk of multiple SCCs increased around sixfold in those aged ≥ 60 years and in those with previous skin cancer, and increased around threefold in those treated with the antifungal medication voriconazole. Multiple BCC risk rose threefold from age 60 years and tenfold for patients with previous skin cancer. CONCLUSIONS: Lung transplant recipients have very high incidence of multiple primary skin cancers. Close surveillance and assiduous prevention measures are essential. Linked Comment: Proby and Harwood. Br J Dermatol 2020; 183:416-417.


Subject(s)
Carcinoma, Basal Cell , Skin Neoplasms , Adolescent , Adult , Aged , Carcinoma, Basal Cell/epidemiology , Humans , Incidence , Lung , Middle Aged , Prospective Studies , Queensland/epidemiology , Risk Factors , Skin Neoplasms/epidemiology , Transplant Recipients
8.
J Econ Entomol ; 112(6): 2719-2730, 2019 12 09.
Article in English | MEDLINE | ID: mdl-31504648

ABSTRACT

The invasive sugarcane aphid, Melanaphis sacchari (Zehntner), is a devastating new pest of grain sorghum. Studies were conducted utilizing an integrated approach of four management tactics: planting date, insecticidal seed treatment, a foliar-applied insecticide, and plant resistance. Experiments were conducted in 2016 and 2017 at Griffin, Tifton, and Plains Georgia, and in 2016 in Texas, Alabama, and Oklahoma, United States. Early planting was effective in reducing damage and increasing yields when compared to the late planting. Use of a resistant variety reduced cumulative aphid-days, plant injury and usually prevented significant yield loss. Foliar application of flupyradifurone when aphids reached an economic threshold, was an effective management tactic preventing aphid injury and yield loss. Use of clothianidin seed treatment also reduced aphid injury and yield loss of the susceptible hybrid but generally did not prevent injury and yield loss of the resistant hybrid. We conclude that an earlier planting date coupled with a resistant variety and judicious use of an efficacious foliar-applied insecticide can effectively manage sugarcane aphid on grain sorghum. An insecticide seed treatment also may be useful to reduce the risk of sugarcane aphid damage to seedlings of susceptible hybrids.


Subject(s)
Aphids , Insect Control , Sorghum , Alabama , Animals , Georgia , Oklahoma , Texas
9.
J Econ Entomol ; 112(3): 1251-1259, 2019 05 22.
Article in English | MEDLINE | ID: mdl-30816948

ABSTRACT

Sugarcane aphid, Melanaphis sacchari Zehtner (Hemiptera: Aphididae), outbreaks on grain sorghum were first detected in the United States in 2013. The spread of sugarcane aphid across the sorghum-producing regions of North America necessitated increased insecticide use to mitigate economic loss. A field experiment to develop economic thresholds for sugarcane aphid was conducted 15 times across seven locations across the southern United States during 3 yr (2014-2016). Grain sorghum hybrids were evaluated by measuring yield in response to a range of aphid infestations. Yield-aphid population density relationships were described by linear function, which facilitated calculating economic injury levels and economic thresholds. The slopes of the yield-aphid density regressions were significant, negative, and relatively stable across locations, years, and agronomic conditions. The relationships aggregated into two groups, populations that exhibited relatively slow and fast population growth, and common economic injury levels were determined using control costs and market values of grain. Average economic injury levels of 37 and 102 aphids per leaf were most applicable to the two groupings of sorghum/aphid relationships and aphid population growth. Using field-based sugarcane aphid population doubling time estimated from weekly observations of aphid densities, economic thresholds were calculated, ranging from 19 to 132 aphids per leaf across the 15 locations-years. Without site-specific knowledge of a slow-growing aphid population and given cost and market price variability of the system, a 40 aphid per leaf threshold is most prudent to use across the range of hybrid, environmental, and market conditions experienced in this study.


Subject(s)
Aphids , Insecticides , Sorghum , Animals , Crops, Agricultural/economics , North America
10.
Int J Obstet Anesth ; 38: 10-18, 2019 05.
Article in English | MEDLINE | ID: mdl-30770209

ABSTRACT

BACKGROUND: Formal reference ranges for rotational thromboelastometry (ROTEM®) in pregnancy have not been obtained in the recommended minimum sample size of 120. This prospective observational study aimed to establish baseline parameters in an Australian population of women undergoing elective caesarean delivery. The secondary aim was to compare these reference ranges with those from prior studies and the manufacturer. METHODS: Women undergoing elective caesarean delivery at term were included if they were at term, of normal body mass index and had no conditions affecting coagulation. ROTEM® reference ranges were derived by calculating the 2.5 and 97.5 percentiles for INTEM/EXTEM/FIBTEM amplitude at 5 minutes (A5), amplitude at 15 minutes (A15), coagulation time (CT), maximum clot firmness (MCF), and clot formation time (CFT). RESULTS: Of 202 women screened, 132 met the inclusion criteria, having a mean age of 32.7 ±â€¯5.0 years and median body mass index of 23.8 kg/m2 (interquartile range 21.5-26.4). The reference ranges for selected ROTEM® parameters were as follows: FIBTEM A5 (13-28 mm), FIBTEM CT (40-74 s), FIBTEM MCF (16-34 mm), EXTEM A5 (39-66 mm), EXTEM CT (43-69 s), INTEM A5 (38-63 mm). CONCLUSIONS: ROTEM® reference ranges for women with uncomplicated term pregnancies were reported as per the International Federation of Clinical Chemistry. The FIBTEM MCF and FIBTEM/EXTEM/INTEM amplitudes were higher in comparison to the manufacturer's reference ranges for the non-obstetric population. The EXTEM CT was shorter than the non-obstetric reference ranges. These ranges show an increase in coagulability during normal pregnancy compared to the non-pregnant reference ranges.


Subject(s)
Blood Coagulation/physiology , Cesarean Section , Elective Surgical Procedures , Thrombelastography/methods , Thrombelastography/statistics & numerical data , Adult , Australia , Body Mass Index , Female , Humans , Pregnancy , Prospective Studies
11.
Astrophys J Suppl Ser ; 239(2)2018 Dec.
Article in English | MEDLINE | ID: mdl-30948861

ABSTRACT

We present a large ensemble of simulations of an Earth-like world with increasing insolation and rotation rate. Unlike previous work utilizing idealized aquaplanet configurations we focus our simulations on modern Earth-like topography. The orbital period is the same as modern Earth, but with zero obliquity and eccentricity. The atmosphere is 1 bar N2-dominated with CO2=400 ppmv and CH4=1 ppmv. The simulations include two types of oceans; one without ocean heat transport (OHT) between grid cells as has been commonly used in the exoplanet literature, while the other is a fully coupled dynamic bathtub type ocean. The dynamical regime transitions that occur as day length increases induce climate feedbacks producing cooler temperatures, first via the reduction of water vapor with increasing rotation period despite decreasing shortwave cooling by clouds, and then via decreasing water vapor and increasing shortwave cloud cooling, except at the highest insolations. Simulations without OHT are more sensitive to insolation changes for fast rotations while slower rotations are relatively insensitive to ocean choice. OHT runs with faster rotations tend to be similar with gyres transporting heat poleward making them warmer than those without OHT. For slower rotations OHT is directed equator-ward and no high latitude gyres are apparent. Uncertainties in cloud parameterization preclude a precise determination of habitability but do not affect robust aspects of exoplanet climate sensitivity. This is the first paper in a series that will investigate aspects of habitability in the simulations presented herein. The datasets from this study are opensource and publicly available.

12.
Environ Entomol ; 46(4): 855-863, 2017 08 01.
Article in English | MEDLINE | ID: mdl-28595271

ABSTRACT

Oviposition preference and host suitability of the Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), on bioenergy and conventional cultivars of sugarcane, Saccharum spp., and sorghum, Sorghum spp., were examined in a series of greenhouse experiments. Two energycane cultivars, two sugarcane cultivars, two high-biomass sorghum cultivars, and one sweet sorghum cultivar were assessed at two phenological stages (immature and mature). Mature plants possessed greater availability of dry leaf material compared with immature plants, and all E. loftini eggs were observed exclusively on dry leaves. Oviposition did not vary among host combinations (cultivar by phenological stage); however, eggs per plant and eggs per oviposition event were numerically greater on mature plants than immature plants. In a no-choice experiment, survival from egg to adult did not vary among host combinations, with <2.0% of E. loftini larvae surviving to adulthood. Failed establishment by neonates on plants was 13.4- to 53.9-fold greater than successful establishment across all host combinations. Results from this study suggest that plant physical characteristics continue to play an important role in host selection, but further evaluations will be needed to quantify other characteristics which influence host suitability.


Subject(s)
Moths/physiology , Oviposition , Saccharum/growth & development , Sorghum/growth & development , Animals , Female , Larva/growth & development , Larva/physiology , Longevity , Moths/growth & development , Saccharum/genetics , Sorghum/genetics , Texas
13.
J Econ Entomol ; 110(1): 150-156, 2017 02 01.
Article in English | MEDLINE | ID: mdl-28053210

ABSTRACT

The Mexican rice borer, Eoreuma loftini (Dyar), is a major pest of sugarcane, Saccharum spp., rice, Oryza sativa L., and other graminaceous crops in Texas and Louisiana. The ability of conventional and electronic pheromone traps to monitor E. loftini in sugarcane and rice habitats was evaluated in two separate 2-yr field studies. Bucket traps baited with a synthetic female sex pheromone monitored E. loftini populations in commercial sugarcane fields in Calcasieu and Jefferson Davis Parishes throughout the 2014 and 2015 growing seasons. The number of E. loftini captured differed among months, but not between years or parishes. The percentage of E. loftini-injured stalks was greater in 2015 than in 2014, peaking in September of both years. Daily trap capture was correlated with the percentage of injured stalks. Injury from E. loftini in Louisiana sugarcane remained relatively low (<3% bored internodes) in both 2014 and 2015. In a second experiment, electronic traps were compared with conventional pheromone traps for monitoring E. loftini populations in sugarcane and rice habitats in Texas in 2013 and 2015. Performance of earlier electronic trap prototypes in 2013 was inconsistent and less effective than conventional traps. Improved trap design in 2015 resulted in more than threefold greater moth capture in electronic traps than in conventional pheromone traps. Electronic traps demonstrated potential to improve monitoring strategies for this pest and should be evaluated for lepidopterous pests in a variety of cropping systems.


Subject(s)
Moths/physiology , Pheromones/pharmacology , Sex Attractants/pharmacology , Animals , Ecosystem , Female , Insect Control , Larva/growth & development , Larva/physiology , Louisiana , Male , Moths/growth & development , Oryza/growth & development , Population Dynamics , Saccharum/growth & development , Seasons
14.
Astrophys J ; 839(1)2017 Apr 10.
Article in English | MEDLINE | ID: mdl-29628519

ABSTRACT

We demonstrate the effectiveness of a relatively straightforward analysis of the complex 3D Fourier transform of galaxy coordinates derived from redshift surveys. Numerical demonstrations of this approach are carried out on a volume-limited sample of the Sloan Digital Sky Survey redshift survey. The direct unbinned transform yields a complex 3D data cube quite similar to that from the Fast Fourier Transform (FFT) of finely binned galaxy positions. In both cases deconvolution of the sampling window function yields estimates of the true transform. Simple power spectrum estimates from these transforms are roughly consistent with those using more elaborate methods. The complex Fourier transform characterizes spatial distributional properties beyond the power spectrum in a manner different from (and we argue is more easily interpreted than) the conventional multi-point hierarchy. We identify some threads of modern large scale inference methodology that will presumably yield detections in new wider and deeper surveys.

15.
Anaesth Intensive Care ; 44(1): 111-8, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26673597

ABSTRACT

A voluntary, anonymous, cross-sectional online survey was conducted among 997 Fellows of the Australian and New Zealand College of Anaesthetists, using an electronic questionnaire. Details about their demographics, employment, research experience and barriers they had encountered, their perception about research and their future intentions to participate in research, were collected. The survey response rate was 24.6%. At the time of the survey, 29% of the survey respondents were involved in research. Respondents currently involved in research were more likely to be practising at a tertiary hospital, to have previously presented at conferences, to believe in the importance of research and to intend to undertake further research training (P <0.05). Time constraints were the most commonly cited reason for not currently performing research. Those who were involved in research spent about 6.3 more hours per week in public practice than those who were not (P=0.012) and had about 4.4 more hours per week of non-clinical time (P <0.001). In terms of barriers encountered during previous projects, 91% of the respondents cited methodological issues, which included complicated ethics approval processes, difficulty in coordinating teams or recruiting participants, non-compliant patients and difficulty in publishing. Sixty-three percent of those surveyed believed more exposure to research activities during training would increase the number of anaesthetists involved in research and scholarly activities. Through this survey, we have identified several areas that, if satisfactorily addressed, could enhance interest and participation in research amongst anaesthetists in Australia and New Zealand.


Subject(s)
Anesthesiology , Biomedical Research , Adult , Aged , Anesthesiology/education , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , New Zealand
16.
Geophys Res Lett ; 43(16): 8376-8383, 2016 Aug 28.
Article in English | MEDLINE | ID: mdl-28408771

ABSTRACT

Present-day Venus is an inhospitable place with surface temperatures approaching 750K and an atmosphere 90 times as thick as Earth's. Billions of years ago the picture may have been very different. We have created a suite of 3-D climate simulations using topographic data from the Magellan mission, solar spectral irradiance estimates for 2.9 and 0.715 Gya, present-day Venus orbital parameters, an ocean volume consistent with current theory, and an atmospheric composition estimated for early Venus. Using these parameters we find that such a world could have had moderate temperatures if Venus had a rotation period slower than ~16 Earth days, despite an incident solar flux 46-70% higher than Earth receives. At its current rotation period, Venus's climate could have remained habitable until at least 715 million years ago. These results demonstrate the role rotation and topography play in understanding the climatic history of Venus-like exoplanets discovered in the present epoch.

17.
J Integr Pest Manag ; 7(1): 7, 2016 Jan.
Article in English | MEDLINE | ID: mdl-28670487

ABSTRACT

The Mexican rice borer, Eoreuma loftini (Dyar), is an invasive pest of rice, Oryza sativa L., in the Gulf Coast region of the United States. This pest also damages sugarcane, Saccharum spp. hybrids; corn, Zea mays L.; and sorghum, Sorghum bicolor (L.) Moench, and feeds on weedy noncrop grasses. Multiple aspects of integrated pest management including use of pheromone traps, manipulation of planting dates, harvest cutting height, stubble management, noncrop host management, soil fertility management, host plant resistance, use of insecticides, and biological control have been studied for Mexican rice borer management. However, the current management strategy in rice primarily relies on the use of chlorantraniliprole insecticide seed treatments. This profile addresses Mexican rice borer biology and management in rice in the United States.


El barrenador mexicano del arroz [Eoreuma loftini (Dyar)] es una plaga invasora de arroz (Oryza sativa L.) en la región de la Costa del Golfo de Estados Unidos. Esta plaga también afecta híbridos de caña de azúcar (Saccharum spp.), maíz (Zea mays L.), sorgo [Sorghum bicolor (L.) Moench), y se alimenta de malezas gramíneas. Múltiples aspectos del manejo integrado de plagas incluyendo el uso de trampas con feromonas, la manipulación de las fechas de siembra, la altura del corte durante la cosecha, el manejo de rastrojos, el manejo de hospederos alternos, el manejo de la fertilidad del suelo, la resistencia de la plantas, el uso de insecticidas y el control biológico han sido estudiados para el manejo del barrenador mexicano del arroz. Sin embargo, la estrategia de actual de manejo en arroz se basa principalmente en el tratamiento químico de la semilla con el uso del insecticida clorantraniliprol. Esta revisión se enfoca en la biología y manejo del barrenador mexicano del arroz en arroz en los Estados Unidos.

18.
J Integr Pest Manag ; 7(1): 12, 2016 Jan.
Article in English | MEDLINE | ID: mdl-28446991

ABSTRACT

In 2013, the sugarcane aphid, Melanaphis sacchari (Zehntner) (Hemiptera: Aphididae), a new invasive pest of sorghum species in North America, was confirmed on sorghum in 4 states and 38 counties in the United States. In 2015, the aphid was reported on sorghum in 17 states and over 400 counties as well as all sorghum-producing regions in Mexico. Ability to overwinter on living annual and perennial hosts in southern sorghum-producing areas and wind-aided movement of alate aphids appear to be the main factors in its impressive geographic spread in North America. Morphological characteristics of the sugarcane aphid include dark tarsi, cornicles, and antennae, allowing easy differentiation from other aphids on the crop. Sugarcane aphid damages sorghum by removing sap and covering plants with honeydew, causing general plant decline and yield loss. Honeydew and sooty mold can disrupt harvesting. The aphid's high reproductive rate on susceptible sorghum hybrids has resulted in reports of yield loss ranging from 10% to greater than 50%. In response, a combination of research-based data and field observations has supported development of state extension identification, scouting, and treatment guides that aid in initiating insecticide applications to prevent yield losses. Highly efficacious insecticides have been identified and when complemented by weekly scouting and use of thresholds, economic loss by sugarcane aphid can be minimized. Some commercial sorghum hybrids are partially resistant to the aphid, and plant breeders have identified other lines with sugarcane aphid resistance. A very diverse community of predators and parasitoids of sugarcane aphid has been identified, and their value to limit sugarcane aphid population growth is under investigation.

19.
J Geophys Res Space Phys ; 121(4): 3139-3154, 2016 Apr.
Article in English | MEDLINE | ID: mdl-29552437

ABSTRACT

We present initial analysis and conclusions from plasma observations made during the reported "Mars plume event" of March - April 2012. During this period, multiple independent amateur observers detected a localized, high-altitude "plume" over the Martian dawn terminator [Sanchez-Lavega et al., Nature, 2015, doi:10.1038/nature14162], the cause of which remains to be explained. The estimated brightness of the plume exceeds that expected for auroral emissions, and its projected altitude greatly exceeds that at which clouds are expected to form. We report on in-situ measurements of ionospheric plasma density and solar wind parameters throughout this interval made by Mars Express, obtained over the same surface region, but at the opposing terminator. Measurements in the ionosphere at the corresponding location frequently show a disturbed structure, though this is not atypical for such regions with intense crustal magnetic fields. We tentatively conclude that the formation and/or transport of this plume to the altitudes where it was observed could be due in part to the result of a large interplanetary coronal mass ejection (ICME) encountering the Martian system. Interestingly, we note that the only similar plume detection in May 1997 may also have been associated with a large ICME impact at Mars.

20.
J Econ Entomol ; 108(5): 2296-304, 2015 10.
Article in English | MEDLINE | ID: mdl-26453718

ABSTRACT

The Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae) is an invasive stem borer of sugarcane, Saccharum spp., and sorghum, Sorghum bicolor (L.), and poses a threat against the production of dedicated bioenergy feedstocks in the U.S. Gulf Coast region. A 2-yr field study was conducted in Jefferson County, TX, to evaluate yield losses associated with E. loftini feeding on bioenergy and conventional cultivars of sugarcane and sorghum under natural and artificially established E. loftini infestations. Bioenergy sugarcane (energycane) 'L 79-1002' and 'Ho 02-113' and sweet sorghum 'M81E' exhibited reduced E. loftini injury; however, these cultivars, along with high-biomass sorghum cultivar 'ES 5140', sustained greater losses in fresh stalk weight. Negative impacts to sucrose concentration from E. loftini injury were greatest in energycane, high-biomass sorghum, and sweet sorghum cultivars. Even under heavy E. loftini infestations, L 79-1002, Ho 02-113, and 'ES 5200' were estimated to produce more ethanol than all other cultivars under suppressed infestations. ES 5200, Ho 02-113, and L 79-1002 hold the greatest potential as dedicated bioenergy crops for production of ethanol in the Gulf Coast region; however, E. loftini management practices will need to be continued to mitigate yield losses.


Subject(s)
Herbivory , Moths/physiology , Saccharum/growth & development , Sorghum/growth & development , Animals , Biomass , Feeding Behavior , Larva/growth & development , Larva/physiology , Moths/growth & development , Population Density , Texas
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