The sugarcane borer, Diatraea saccharalis (F.), is a major target of transgenic maize expressing Bacillus thuringiensis (Bt) proteins in South America and the mid-Southern region of the United ...States. During 2007–2009, a total of 986 feral individuals of D. saccharalis were collected from maize fields in six locations of Louisiana and Mississippi and examined for resistance to Cry1Ab maize using F1/F2 screens. Major resistance alleles to Cry1Ab maize in the populations sampled from non-Bt maize plants during 2007 and 2008 in Louisiana and 2009 in Mississippi were rare. From a total of 487 individuals collected from three locations in Louisiana in 2007 and 2008, only one individual was identified with major resistance alleles. In addition, no major resistance alleles were detected in 242 individuals collected from three locations in Mississippi in 2009. The frequency of major resistance alleles was estimated to be 0.002 with a 95% CI of 0.00025–0.0057 for the Louisiana populations and < 0.0061, with 95% probability, for the Mississippi populations. The resistance frequency estimated for the Louisiana populations in 2007 and 2008 was not significantly different from those reported previously for populations sampled in 2004–2006. However, among 200 individuals sampled from non-Bt maize plants in 2009 in Louisiana, six individuals were identified to possess major resistance alleles. The estimated major resistance allele frequency for the populations sampled from non-Bt maize plants in 2009 in Louisiana was 0.0176 with a 95% CI of 0.0072 to 0.0328, which was significantly greater than those estimated for the populations collected in 2004–2008. Similarly, the frequency of minor resistance alleles to Cry1Ab maize for the Louisiana populations collected in 2009 was also significantly greater than those estimated for the populations sampled before. In addition, two out of 57 feral individuals collected from Bt maize plants in Louisiana in 2009 were identified to carry major resistance alleles to Cry1Ab maize. Since 2010, transgenic maize expressing pyramided Bt genes has been planted in the US mid-Southern region and by 2011, pyramided Bt maize has replaced Cry1Ab maize as the dominant Bt maize for managing lepidopteran pests including D. saccharalis. The timely switching from single-gene Cry1Ab maize to the pyramided Bt maize should prevent further increases in Cry1Ab resistance allele frequency and thus ensure the continued success of Bt maize for managing D. saccharalis in the region.
An antiferromagnetic (AFM) Kondo lattice compound CeRhAl4Si2, which exhibits successive AFM transitions at TN1=14 K and TN2=9 K in zero external field, has been microscopically investigated by means ...of 27Al nuclear magnetic resonance (NMR) technique. In the high temperature range, magnetic excitations of 4f electrons can be well explained by isotropic localized spin fluctuations. Below ∼50 K, it begins to show a characteristic anisotropy of spin fluctuations, which suggests a competition between spin fluctuations and nesting instability in this system.
Climate change has received significant attention lately as it has adverse environmental impacts. Among them, rising water levels in the reservoirs are of key concern for infrastructures such as ...dams. Dam officials are compelled to reconsider dam safety with the increment in catastrophic floods and accelerated dam failure issues. Relatedly, there are numerous earthen dams in the US that may not be up to the current design standards as these dams are aging. They possess a higher risk of failure due to various factors such as defects in design geometry, geologic materials, and hydrologic deficiency due to extreme storms associated with changing climate. Hence, this study focuses on evaluating the impacts of climate change on earthen dams and spillways by conducting a post-failure analysis of the two cascading dams, Edenville Dam and Sanford Dam, located in Michigan, USA, that failed in series in May 2020. The study aims to accomplish three main objectives: 1) to identify the role of climate change on recent dam failures of Edenville and Sanford, 2) to perform a Windows Dam Analysis Modules (WinDAM) C simulation for the failure analysis of the two dams, and 3) to perform Hydrologic Engineering Center - River Analysis System (HEC-RAS) simulation for the failure analysis of both dams by observing downstream propagation of flood with the detailed evaluation of depth and velocity. The overall results show that extreme storms and flooding are associated with the increase in temperature and precipitation rates, impacting overall dam safety. Careful precautions should be undertaken before any of these catastrophic dam events occur. The analysis is useful for the dam agencies as they reconsider their guidelines and policies for future updates.
The Government of Nepal promulgated health as a human right via Interim constitution and implemented Free Health Service Program in 2008 as a commitment to universalize basic health care services. ...So, the aim of this study was to understand reported access to medicine and health care services received by outpatients in public primary facilities.
The study followed cross sectional study design. Two hundred and thirty-four For data 234 out patients were interviewed on the day of the field visit in March and October 2014 across 28 primary health facilities of seven purposively selected districts representing three ecological belts and five development regions of the country.
Our study revealed that the average number of medicines prescribed per patient was 2.65 per case in primary public health facilities, of which 91.2% were dispensed. Around 86.6% dispensed medicines were appropriately labeled and 84% of outpatients had proper knowledge of dosage and timing of medicine use. Around 55.6% of outpatients purchased some or all prescribed medicines from nearby private facilities which were not available in public facilities. Around 40% of them travelled more than half an hour to reach the facility.
The gap in medicines prescribed and dispensed, Out of Pocket expenditure coupled with opportunity cost of travelling, appear as hurdles in access to basic health care services. So increasing free medicines list in public primary facilities with all round the year availability might answer major part of the problem.
The adsorption behavior of lead (II), zinc (II) and copper (II) on crosslinked pectic and alginic acids, and their amide derivatives form has been investigated. The selectivity order for metal ion ...uptake is lead (II) > copper (II) > zinc (II). The nature of such acidic polysaccharides for the removal of lead (II) ion was examined through batch wise tests and column tests and compared with that for the commercially available weakly acidic cation exchange DIAION WK resins. The experimental results revealed that chemically modified acidic polysaccharides exhibit much better separation performance compared to the latter, which suggests a high possibility of their applications in the practical separation and purification of lead (II) ion.
The khapra beetle, Trogoderma granarium, is an important quarantine pest of stored-products. While it is not established in the North America, frequent interceptions highlight the need for treatments ...to eradicate isolated populations if they occur. Methyl bromide has long been the standard fumigant used for this purpose; however, increasing restrictions on its use necessitate the development of new treatment options. Here we evaluate a treatment for khapra beetle using a combination of sulfuryl fluoride (SF) and propylene oxide (PPO). Experiments were conducted to determine the most tolerant stages and the effective rates for each compound. Combination treatments using both products were then evaluated at several temperatures to determine effective doses for quarantine level control. The egg stage was by far the most tolerant to SF, requiring concentration × time (CT) products roughly 10-fold greater than the next most tolerant stage, diapausing larvae. Diapausing larvae were significantly more tolerant to SF than non-diapausing larvae in a recently collected ‘field' strain, but not in a more than 30-yr-old ‘laboratory’ culture. PPO treatments were shown to completely control the egg stage at CTs greater than 155 hr-mgL-1 at both 10 and 20°C. Resulting combination treatments with initial dose rates of 96 and 40 mgL-1 at 10°C and 80 and 40 mgL-1 at 20°C are proposed for SF and PPO, respectively.These combination treatments utilize SF's efficacy against the larval stage along with PPO's superior ovicidal properties to provide enhanced treatment efficacy over each product alone against all life stages of khapra beetle.
Transgenic crops that produce Bacillus thuringiensis (Bt) toxins are grown widely for pest control, but insect adaptation can reduce their efficacy. The genetically modified Bt toxins Cry1AbMod and ...Cry1AcMod were designed to counter insect resistance to native Bt toxins Cry1Ab and Cry1Ac. Previous results suggested that the modified toxins would be effective only if resistance was linked with mutations in genes encoding toxin-binding cadherin proteins. Here we report evidence from five major crop pests refuting this hypothesis. Relative to native toxins, the potency of modified toxins was >350-fold higher against resistant strains of Plutella xylostella and Ostrinia nubilalis in which resistance was not linked with cadherin mutations. Conversely, the modified toxins provided little or no advantage against some resistant strains of three other pests with altered cadherin. Independent of the presence of cadherin mutations, the relative potency of the modified toxins was generally higher against the most resistant strains.
This paper investigates how variations in sediment supply, grain size distribution and climate change affect channel morphology and flood inundation in the Nakkhu River, Kathmandu, Nepal. Climate ...change‐induced extreme rainfall is expected to increase flood intensity and frequency, causing severe flooding in the Kathmandu basin. The upper reaches of the Nakkhu River are susceptible to landslides and have been impacted by large‐scale sand mining. We simulate potential erosion and deposition scenarios along a 14 km reach of the Nakkhu River using the landscape evolution model CAESAR‐Lisflood with a 10 m digital elevation model, field‐derived sediment grain size data, daily discharge records and flood forecast models. In a series of numerical experiments, we compare riverbed profiles, cross‐sections, flood extent and flow depths for three scenarios (1.2‐, 85‐ and 1000‐year return period floods). For each scenario, the model is first run without sediment transport and then with sediment transport for three grain size distributions (GSDs) (observed average, finer and coarser). In all cases, the inclusion of sediment led to predicted floods of a larger extent than estimated without sediment. The sediment grain size distribution was found to have a significant influence on predicted river morphology and flood inundation, especially for lower magnitude, higher probability flood events. The results emphasise the importance of including sediment transport in hydrological models when predicting flood inundation in sediment‐rich rivers such as those in and around the Himalaya.
Including sediment transport in flood hazard modelling can result in a larger inundation area and greater flood hazard, in addition to a change in river morphology. For low‐intensity, high‐frequency flood events, flood inundation is highly sensitive to sediment grain size distribution, but the importance of accurately estimating grain size distribution becomes less significant for extreme, high‐intensity flood events.
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