LC-Biosensor System for the Determination of the Neurotoxin β-N-Oxalyl-l-α,β-diaminopropionic Acid

An analysis system is described for the determination of the neurotoxin β-N-oxalyl-l-α,β-diaminopropionic acid (β-ODAP). The system is based on liquid chromatographic separation of β-ODAP from interfering amino acids on an anion exchange column coupled with an amperometric enzyme electrode for the registration of β-ODAP. The electrode is based on a graphite rod modified with an Os(2+/3+) redox polymer cross-linked with l-glutamate oxidase and horseradish peroxidase. This LC-bienzyme electrode analytical system enabled monitoring of as low as 4 μM β-ODAP (injection volume 100 μL). The β-ODAP content in real grass pea samples was measured to range between 3.3 and 5.2 g kg(-)(1) in dry grass pea.     

Preparation and characterization of graphene‐agar and graphene oxide‐agar composites

Biodegradable counterparts of petro plastics for packaging applications are highly desired due to environmental considerations. Agar can be a potential material due to its availability and biodegradability. However, moderate mechanical strength and thermal stability, in addition to poor resistance against water, needs to be addressed before agar can be commercially implemented as packaging material. As a step toward this objective, graphene oxide (GO) and reduced GO (RGO) were incorporated in agar and were solution casted in the form of films. The tensile strength was increased by 118.4% and 69.4% at 2% GO and 2% RGO loading, respectively. Higher interfacial bonding between GO and agar compared to that of RGO and agar was attributed for the observed mechanical properties. Resistance to swelling and hydrophobicity (contact angle) of the composite were improved as well when compared to pure agar. The tensile strength and the contact angle values were however, decreased after the addition of 2% GO and 2% RGO. The morphological investigation showed that the formation of pores at higher concentration of reinforcement was the contributing factor for the decrease in tensile strength. No significant change in thermal properties was observed. The transmittance value was reduced to 0% after the incorporation of GO and RGO. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45085.     

Supporting adaptive capacity of agropastoralists through fish production and marketing: The case of Tendaho Reservoir

The present study was conducted to share the experience of promoting fish production and marketing from the Tendaho Reservoir of the Afar region, Ethiopia. The study results indicate the reservoir is serving its purpose, namely to generate gainful employment for the pastoralist youth and to create sustainable livelihoods and sources of income for the pastoralist‐fishermen of the Afar region. Further, the reservoir fish production has improved the nutrition and food security status of children. It also created a new business entry for hotels and restaurants in the area. Fishermen in the study areas, however, face problems getting the required support for such efforts, in the form of training in fish post‐harvest practices. The present study also indicates dried catfish marketing should be targeted in the short run to address the substantial fish spoilage observed in the high‐production hot season. Dried catfish marketing is highly recommended for the Afar region since it is well adapted to the climate of the study area, noting the product is less perishable and can be sold throughout the country. Dried catfish marketing is also expected to address the problem of gender inclusiveness, an issue clearly missing in the fish production system in the study areas.     

The dynamics of urban expansion and land use/land cover changes using remote sensing and spatial metrics: the case of Mekelle City of northern Ethiopia

Information on the rate and pattern of urban expansion is required by urban planners to devise proper urban planning and management policy directions. This study evaluated the dynamics and spatial pattern of Mekelle City’s expansion in the past three decades (1984–2014). Multi-temporal Landsat images and Maximum Likelihood Classifier were used to produce decadal land use/land cover (LULC) maps. Changes in LULC and spatial pattern of urban expansion were analysed by post-classification change detection and spatial metrics, respectively. The results showed that in the periods 1984–1994, 1994–2004, and 2004–2014, the built-up area increased annually by 10%, 9%, and 8%, respectively; with an average annual increment of 19% (100 ha year^?1), from 531 ha in 1984 to 3524 ha in 2014. Between 1984 and 2014, about 88% of the gain in built-up area was from conversion of agricultural lands, which decreased by 39%. Extension of existing urban areas was the dominant growth type, which accounted for 54%, 75%, and 81% of the total new development during 1984–1994, 1994–2004, and 2004–2014, respectively. The spatial metrics analyses revealed urban sprawl, with increased heterogeneity and gradual dispersion in the outskirts of the city. The per capita land consumption rate (ha per person) increased from 0.009 in 1984 to 0.014 in 2014, indicating low density urban growth. Based on the prediction result, the current (2014) built-up area will double by 2035, and this is likely to have multiple socioeconomic and environmental consequences unless sustainable urban planning and development policies are devised.     

Classification of rose flowers based on Fourier descriptors and color moments

Multimedia Tools and Applications - In this paper, a rose-flower variety classification scheme, using color and shape features is presented. The first three statistical moments of the R, G, and B...     

An empirical study of software release notes

Release notes are an important source of information about a new software release. Such notes contain information regarding what is new, changed, and/or got fixed in a release. Despite the importance of release notes, they are rarely explored in the research literature. Little is known about the contained information, e.g., contents and structure, in release notes. To better understand the types of contained information in release notes, we manually analyzed 85 release notes across 15 different software systems. In our manual analysis, we identify six different types of information (e.g., caveats and addressed issues) that are contained in release notes. Addressed issues refer to new features, bugs, and improvements that were integrated in that particular release. We observe that most release notes list only a selected number of addressed issues (i.e., 6-26 % of all addressed issues in a release). We investigated nine different factors (e.g., issue priority and type) to better understand the likelihood of an issue being listed in release notes. The investigation is conducted on eight release notes of three software systems using four machine learning techniques. Results show that certain factors, e.g., issue type, have higher influence on the likelihood of an issue to be listed in release notes. We use machine learning techniques to automatically suggest the issues to be listed in release notes. Our results show that issues listed in all release notes can be automatically determined with an average precision of 84 % and an average recall of 90 %. To train and build the classification models, we also explored three scenarios: (a) having the user label some issues for a release and automatically suggest the remaining issues for that particular release, (b) using the previous release notes for the same software system, and (c) using prior releases for the current software system and the rest of the studied software systems. Our results show that the content of release notes vary between software systems and across the versions of the same software system. Nevertheless, automated techniques can provide reasonable support to the writers of such notes with little training data. Our study provides developers with empirically-supported advice about release notes instead of simply relying on adhoc advice from on-line inquiries.     

Loss mechanisms in single-mode fiber tapers

The onset of transmission loss in four single-mode tapers is shown to coincide with the taper slope exceeding the critical slope angle at which fundamental mode cutoff occurs. This implies that the primary loss mechanism in single-mode fiber tapers is cutoff of the fundamental mode from the core. A secondary loss mechanism of coupling to the modes of a coaxial outer waveguide is also observed and modeled. Implications for fused fiber couplers are discussed.     

Current-voltage characteristics from an asymptotic analysis of the MOSFET equations

Phenomenological formulae for the current-voltage characteristics of a MOSFET are derived by extending the asymptotic method of Ward. Practical methods for combining the perturbation approximations and numerically implementing the Ward equations are developed. A detailed comparison with real MOSFET data is presented and the model is shown to be effective over a range of device geometries.     

Maternal regulation of embryonic growth: the role of vasoactive intestinal peptide

Vasoactive intestinal peptide (VIP) is an important growth regulator of the embryonic day (E)9-E11 mouse. In comparably aged rat embryos, VIP messenger RNA (mRNA) is not detectable; however, peak concentrations of VIP in maternal rat serum indicate a nonembryonic source. In the current study, mouse maternal and embryonic tissues were examined from E6-E12. Although RT-PCR revealed VIP mRNA in E6-E7 conceptuses, by E8 (when extraembryonic tissues could be separated from the embryo), VIP mRNA was detected only in the decidua/trophoblast. Decidual/trophoblastic VIP mRNA decreased until E10, after which it was not detectable. VIP mRNA was not apparent in the embryo until E11-E12. At E9, VIP immunoreactivity was localized to abundant, diffuse cells in the decidua basalis, which were also immunoreactive for T cell markers. VIP binding sites were dense in the decidua/trophoblast at E6, but gradually decreased until E10, after which they were not apparent. VIP binding sites were detected in embryonic neuroepithelium by E9. The transient presence of VIP binding sites and mRNA in the decidua/trophoblast correlate with the critical period of VIP growth regulation, when VIP mRNA is absent in the embryo. These findings suggest that maternal lymphocytes are the source of VIP's regulating early postimplantation embryonic growth.