312 research outputs found

    Field assessment of interreplicate variability from eight electromagnetic soil moisture sensors

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    Interreplicate variability—the spread in output values among units of the same sensor subjected to essentially the same condition—can be a major source of uncertainty in sensor data. To investigate the interreplicate variability among eight electromagnetic soil moisture sensors through a field study, eight units of TDR315, CS616, CS655, HydraProbe2, EC5, 5TE, and Teros12 were installed at a depth of 0.30 m within 3 m of each other, whereas three units of AquaSpy Vector Probe were installed within 3 m of each other. The magnitude of interreplicate variability in volumetric water content (θv) was generally similar between a static period near field capacity and a dynamic period of 85 consecutive days in the growing season. However, a wider range of variability was observed during the dynamic period primarily because interreplicate variability in θv increased sharply whenever infiltrated rainfall reached the sensor depth. Interreplicate variability for most sensors was thus smaller if comparing θv changes over several days that excluded this phenomenon than if comparing θv directly. Among the sensors that also reported temperature and/or apparent electrical conductivity, the sensors exhibiting the largest interreplicate variability in these outputs were characterized by units with consistently above or below average readings. Although manufacturers may continue to improve the technology in and the quality control of soil moisture sensors, users would still benefit from paying greater attention to interreplicate variability and adopting strategies to mitigate the consequences of interreplicate variability

    Preventing dentures and putting aside the fry bread: A systematic review of micro, mezzo, and macro conditions for dental health and obesity interventions for Native American youth

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    This systematic literature review was focused on childhood obesity and dental health interventions which have relevance to Native American communities. Childhood oral health and obesity have become significant problems across North America and among Nati

    Isospin splitting in heavy baryons and mesons

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    A recent general analysis of light-baryon isospin splittings is updated and extended to charmed baryons. The measured Σc\Sigma_c and Ξc\Xi_c splittings stand out as being difficult to understand in terms of two-body forces alone. We also discuss heavy-light mesons; though the framework here is necessarily less general, we nevertheless obtain some predictions that are not strongly model-dependent.Comment: 12 pages REVTEX 3, plus 4 uuencoded ps figures, CMU-HEP93-

    Dependency on de novo protein synthesis and proteomic changes during metamorphosis of the marine bryozoan Bugula neritina

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    Background: Metamorphosis in the bryozoan Bugula neritina (Linne) includes an initial phase of rapid morphological rearrangement followed by a gradual phase of morphogenesis. We hypothesized that the first phase may be independent of de novo synthesis of proteins and, instead, involves post-translational modifications of existing proteins, providing a simple mechanism to quickly initiate metamorphosis. To test our hypothesis, we challenged B. neritina larvae with transcription and translation inhibitors. Furthermore, we employed 2D gel electrophoresis to characterize changes in the phosphoproteome and proteome during early metamorphosis. Differentially expressed proteins were identified by liquid chromatography tandem mass spectrometry and their gene expression patterns were profiled using semi-quantitative real time PCR. Results: When larvae were incubated with transcription and translation inhibitors, metamorphosis initiated through the first phase but did not complete. We found a significant down-regulation of 60 protein spots and the percentage of phosphoprotein spots decreased from 15% in the larval stage to12% during early metamorphosis. Two proteins--the mitochondrial processing peptidase beta subunit and severin--were abundantly expressed and phosphorylated in the larval stage, but down-regulated during metamorphosis. MPPbeta and severin were also down-regulated on the gene expression level. Conclusions: The initial morphogenetic changes that led to attachment of B. neritina did not depend on de novo protein synthesis, but the subsequent gradual morphogenesis did. This is the first time that the mitochondrial processing peptidase beta subunit or severin have been shown to be down-regulated on both gene and protein expression levels during the metamorphosis of B. neritina. Future studies employing immunohistochemistry to reveal the expression locality of these two proteins during metamorphosis should provide further evidence of the involvement of these two proteins in the morphogenetic rearrangement of B. neritina

    Water effects on optical canopy sensing for late-season site-specific nitrogen management of maize

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    The interpretation of optical canopy sensor readings for determining optimal rates of late-season site-specific nitrogen application to corn (Zea mays L.) can be complicated by spatially variable water sufficiency, which can also affect canopy size and/or pigmentation. In 2017 and 2018, corn following corn and corn following soybeans were subjected to irrigation×nitrogen fertilizer treatments in west central Nebraska, USA, to induce variable water sufficiency and variable nitrogen sufficiency. The vegetation index-sensor combinations investigated were the normalized difference vegetation index (NDVI), the normalized difference red edge index (NDRE), and the reflectance ratio of near infrared minus red edge over near infrared minus red (DATT) using ACS-430 active optical sensors; NDVI using SRSNDVI passive optical sensors; and red brightness and a proprietary index using commercial aerial visible imagery. Among these combinations, NDRE and DATT were found to be the most suitable for assessing nitrogen sufficiency within irrigation levels. While DATT was the least sensitive to variable water sufficiency, DATT still tended to decrease with decreasing water sufficiency in high nitrogen treatments, whereas the effect of water sufficiency on DATT was inconsistent in low nitrogen treatments. A new method of quantifying nitrogen sufficiency while accounting for water sufficiency was proposed and generally provided more consistent improvement over the mere averaging of water effects as compared with the canopy chlorophyll content index method. Further elucidation and better handling of water-nitrogen interactions and confounding are expected to become increasingly important as the complexity, automation, and adoption of sensor-based irrigation and nitrogen management increase

    Konflik pengambilan tanah Orang Asli: kajian kes di Johor dan Selangor

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    Orang Asli merupakan golongan minoriti yang terdapat di Semenanjung Malaysia. Sistem Torrens yang diamalkan oleh Malaysia melalui Kanun Tanah Negara 1965 hanya memberi kepentingan terhadap tanah yang didaftarkan di Pejabat Pendaftaran Tanah, manakala tanah saka Orang Asli yang diwarisi dari generasi ke generasi tidak termasuk dalam sistem pendaftaran. Objektif kajian ini adalah (1) Mengenalpasti konflik yang berlaku akibat daripada pengambilan tanah Orang Asli yang terlibat, (2) Menganalisis kesan pengambilan tanah terhadap masyarakat Orang Asli yang terlibat dan (3) Menjelaskan usaha penyelesaian konflik pengambilan tanah Orang Asli yang terlibat. Bagi mencapai objektif kajian ini, kaedah kualitatif telah digunakan melalui kaedah temubual semi struktur. Temubual ini telah dijalankan ke atas lima belas responden utama daripada pihak berkepentingan iaitu enam orang Tok Batin dan Penolong Batin bagi setiap kampung yang terlibat, dua pegawai daripada pejabat tanah Negeri Johor dan Selangor, tiga pegawai daripada Jabatan Kemajuan Orang Asli , seorang pegawai daripada Suruhanjaya Hak Asasi Malaysia (SUHAKAM), seorang wakil badan bukan kerajaan iaitu Persatuan Orang Asli Semenanjung Malaysia , dan seorang ahli akademik. Hasil kajian mendapati bahawa terdapat konflik di antara masyarakat Orang Asli, konflik di antara Orang Asli dan Pihak Berkuasa serta konflik di antara agensi kerajaan Negeri dan Persekutuan. Kesan pengambilan tanah dapat dilihat melalui kesan terhadap sosiobudaya, persekitaran dan ekonomi masyarakat Orang Asli yang terlibat. Kaedah penyelesaian bagi pengambilan tanah Orang Asli yang terlibat adalah melalui rundingan, bayaran pampasan, menggunakan saluran mahkamah, Dasar Pemberi Milikan Tanah Orang Asli oleh Jabatan Kemajuan Orang Asli dan Inkuiri Nasional oleh Suruhanjaya Hak Asasi Kemanusiaan Malaysia

    Pumpage Reduction by using Variable Rate Irrigation to Mine Undepleted Soil Water

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    Conventional irrigation schedules are typically based on portions of the field where root zones hold the least available soil water. This leaves undepleted available water in areas with larger water holding capacities. The undepleted water could be used through variable-rate irrigation (VRI) management; however, the benefits of VRI without in-field mapping are unexamined. In this research, the field-averaged amount of undepleted available soil water in the root zone was calculated from the NRCS Soil Survey Geographic database for 49,224 center-pivot irrigated fields in Nebraska. Potential reductions in pumpage from mining undepleted available water were then estimated. Results of the analysis show that widespread adoption of zone control VRI technology based only on the pumping savings from mining undepleted available water may be unwarranted for current VRI costs and average pumping energy expenses in the Central Plains (0.0026m3to0.0026 m-3 to 0.0947 m-3). Pumpage reductions exceeded 51 mm year-1 for only 2% of the fields and exceeded 25 mm year-1 for 13% of the fields; thus, reductions may be small compared to annual pumpage requirements. If VRI were im-plemented on all fields with a potential pumpage reduction greater than 51 or 25 mm year-1, the volume of pumpage reduction would be approximately 0.35% or 1.3%, respectively, of the total irrigation pumpage in Nebraska. These data may be a conservative estimate of pumpage reduction in fields where the measured variability in soil properties exceeds that described by the NRCS Soil Survey, or if undepleted water is mined early in the season and the soil water profile is refilled by precipitation, allowing undepleted water to be mined again. Adoption of zone control VRI is most feasible for fields where the pumpage reduction from VRI is large and pumping costs are above normal. Pivot fields with high un-depleted water were sparsely distributed across Nebraska and were often located along streams and or in associated alluvial areas. The prevalence of fields with large quantities of undepleted water differed among and within soil associations. We were unable to assign feasibility of VRI based on the soil association, as the occurrence of undepleted water varied significantly within a soil association. These findings should assist producers and other entities interested in VRI technology; however, pumpage reduction through use of undepleted soil water is only one benefit of VRI technology and management. Producers are encouraged to consider all potential benefits when analyzing VRI investments

    BTZ-copolymer loaded graphene aerogel as new type Green and metal-freevisible light photocatalyst

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    This paper reports a new class of efficient, green and metal-free visible-light photocatalyst made from graphene aerogel (GA) doped with a conjugated porous polymer (CMPs). Hence, we report the synthesis of a benzothiadiazole (BTZ)-based CMP loaded into GA via a one-step hydrothermal reaction between 2D graphene oxide (GO) and the CMP, performed through a green process and under mild conditions. The as-prepared GA showed a bathochromic shift in the UV–vis diffraction reflectance spectroscopy (DRS) absorption edge to 628.5 nm, demonstrating its ability to absorb light in the visible region. SEM, TEM, XPS, EDX mapping results further showed the successful loading of the BTZ-based CMP in the GA array. The synthesized GA was used as a 3D structured photocatalyst for the visible-light-driven photodecomposition of methyl orange (MO) with an efficiency of 89.2% (5 wt% CMP). When compared to that of the pure CMP (86.9%), a comparable yet small increase in the efficiency was observed. This is due to a synergistic effect between GO and loaded polymer in GA array upon the formation of CMPGA hybrid structure via chemical interaction between BTZ-Py and GO throughout the mild hydrothermal reaction, and the enhanced photocatalytic activity exhibited from 1 mg equivalent polymer in the CMPGA2 hybrid when compared to the 20 mg pure polymer. Upon repeated use, the depreciation in photocatalytic activity was low with a <5% drop over 3 cycles. These results showed the CMP-loaded GA as an efficient metal-free photocatalyst and a promising material for further investigation into other photocatalytic applications

    Spatio-temporal modelling of dengue fever incidence in Malaysia

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    Previous studies reported significant relationship between dengue incidence rate (DIR) and both climatic and non-climatic factors. Therefore, this study proposes a generalised additive model (GAM) framework for dengue risk in Malaysia by using both climatic and non�climatic factors. The data used is monthly DIR for 12 states of Malaysia from 2001 to 2009. In this study, we considered an annual trend, seasonal effects, population, population density and lagged DIR, rainfall, temperature, number of rainy days and El Niño-Southern Oscillation (ENSO). The population density is found to be positively related to monthly DIR. There are generally weak relationships between monthly DIR and climate variables. A negative binomial GAM shows that there are statistically significant relationships between DIR with climatic and non-climatic factors. These include mean rainfall and temperature, the number of rainy days, sea surface temperature and the interaction between mean temperature (lag 1 month) and sea surface temperature (lag 6 months). These also apply to DIR (lag 3 months) and population density
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