Seasonal decline in breeding performance of the Kelp Gull Larus dominicanus

The effects of timing of breeding on reproductive parameters of Kelp Gulls Larus dominicanus were studied in Patagonia, Argentina, during 1998 and 1999. Yearly and spatial variation in the study were assessed by sampling nests during two field seasons and in different areas within the colony, and accounted for variation with respect to breeding synchrony and breeding density. In both years and in three study areas, individuals laying earlier had higher hatching success, a larger number of chicks fledged, heavier chicks at one month and higher breeding success. Significant variation between study areas within the colony and between years was observed only for breeding success and number of chicks fledged. No effects of breeding synchrony on breeding parameters were detected. Timing of breeding, independent of study year and area, had no effect on either clutch size or egg size. Our results document for the first time the seasonal decline in breeding performance in the Kelp Gull, a species widely distributed in the southern hemisphere.Fil: Garcia Borboroglu, Jorge Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Yorio, Pablo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Moreno, Juan. Consejo Superior de Investigaciones Científicas; EspañaFil: Potti Sánchez, Jaime. Consejo Superior de Investigaciones Científicas; Españ

On the Design of Web Services: SOAP vs. REST

The purpose of this thesis is to compare the performance characteristics of Simple Object Access Protocol (SOAP) and Representational State Transfer (REST), which are methods of supporting interactions among Web services. They differ in both context and usage; SOAP is a protocol while REST is architecture. SOAP is a well-developed protocol used in the Web industry and is standardized by the World Wide Web Consortium (W3C). REST is the outcome of Dr. Roy Thomas Fielding’s 2000 PhD dissertation, “Architectural Styles and the Design of Network-Based Software Architecture.” REST is gaining in popularity due to its simplicity, scalability, and architectural dependence on the World Wide Web. Major software companies, such as Google and Amazon, among others, have started using REST. The main difference between the two methods is SOAP is a tightly coupled system, whereas REST is a loosely coupled system; both have advantages and disadvantages. We built SOAP and REST based Web services that performed the GET, POST, PUT, and DELETE functions on a database. We utilized response time and throughput metrics to compare the performance of these Web services. In comparing the two technologies, we found REST was considerably faster, compared to SOAP, because the response times of REST were better than those of SOAP. As an ancillary outcome, we found building Web services using SOAP was easier, due to considerable tool support, whereas developing Web services using REST was time consuming, as it provides no tool support

Evaluation of Actual Timetables and Utilization Levels of West Midlands Metro Using Event-Based Simulations

The performance of the West Midlands Metro in the United Kingdom is analyzed in the present study by evaluating the existing timetables of the metro system. Using SIMUL8 computer software, a discrete event-based simulation prototype modeling the metro system is developed and implemented. The model adequately describes the performance of the West Midlands Metro system. By running simulations, the overall utilization level of the metro system is calculated. The results of the simulation model indicate that the metro system is being underutilized. The low utilization rates indicate a potential for the introduction of new services capable of exploiting the existing infrastructure and improving the utilization levels of the existing metro system; For example, the potential of using the current metro system for urban freight transport could be a new service of interest and provide scope for further research

Testing the matching habitat choice hypothesis in nature: phenotype-environment correlation and fitness in a songbird population

The matching habitat choice hypothesis holds that individuals with different phenotypes actively select the habitats to which they are best adapted, hence maximizing fitness. Despite the potential implications of matching habitat choice for many ecological and evolutionary processes, very few studies have tested its predictions. Here, we use a 26-year dataset on a spatially structured population of pied flycatchers (Ficedula hypoleuca) to test whether phenotype-dependent dispersal and habitat selection translate into increased fitness, as measured by recruitment success. In our study system, males at the extremes of the body size range segregate into deciduous and coniferous forests through nonrandom dispersal. According to the matching habitat choice hypothesis, fitness of large-sized males is expected to be higher in the deciduous habitat, where they preferentially settle to breed, while the reverse would be true for small-sized males, which are more frequent in the coniferous forest. Our results showed that recruitment success in the coniferous forest increased non-linearly with body size, with males at the middle of the size range having higher fitness than both large and small-sized males. However, no clear trend was observed in the deciduous forest where males of either size had similar fitness. After empirically discarding other important processes potentially confounding matching habitat choice, as genotype- and body condition-dependent dispersal, competitive exclusion remains the most likely force shaping the nonrandom distribution of male pied flycatchers. A conclusive demonstration of the operation and occurrence of matching habitat choice in nature remains therefore to be done.Peer reviewe

Significance of non applied elements in coconut productivity

A critical evaluation of nutritional factors involved in coconut productivity was carried out during 1991-1994. West coast tall palms aged 25 to 35 years varying in yield from 6-163 nuts per year growing in three locations. viz. Regional agricultural research station, pilicode , agricultural research station , msnnuthy and coconut research station, Balaramapuram under regular management constituted the experimental material. The relationship of individual nutrient contents in respect of 10 elements were worked out. First order nutrient ratios in respect of these elemets were also studeid. The results showed that continuous use of conventional fertilizers have lead to a stage of negative response for them. It also indicated that deficiency of non recommended and non applied elements like Mg and S and excess of Ca, Fe and Mn limits coconut yield. This points to importance of balanced nutrition for problem management and better productivity in coconut

Uji Aktivitas Antibakteri Ekstrak Etanol Daun Singkong (Manihot Esculenta Crantz) Terhadap Daya Hambat Bakteri Escherichia Coli

Secara farmakologi daun singkong mempunyai aktivitas sebagai antiinflamasi, antibakteri, antioksidan. Kandungan yang terdapat dalam daun singkong yaitu air, fosfor, karbohidrat, kalsium, vitamin c, protein, lemak, vitamin B1, zat besi, flavanoid, saponin, tanin dan triterpenoid. Daun singkong dipercaya memiliki berbagai manfaat untuk pengobatan penyakit seperti dapat mengobati rematik, asam urat, anemia, konstipasi, serta untuk meningkatkan daya tahan tubuh dan dapat pula mengatasi masalah diare. Berdasarkan penelitian sebelumya oleh (Mutia dkk,.2017) mengemukakan bahwa daun singkong (Manihot esculenta Cranz) memiliki kandungan flavonoid,saponin dan tanin yang digunakan sebagai antibakteri. Salah satunya bakteri penyebab diare yaitu Escherisia Coli.Adanya efek anti bakteri pada daun ubi kayu dikarenakan mengandung mengandung senyawa antibakteri yaitu saponin, tannin dan flavonoid. Bakteri Escherisia Coli merupakan mikroorganisme patogen yang sering menginfeksi manusia. Bakteri ini merupakan salah satu yang menyebabkan terjadinya infeksi saluran kemih, meningitis, pneumonia,diare dan infeksi lainnya. Penyebaran bakteri Escherchia Colli dapat melalui kegiatan tangan ke mulut atau dengan cara pemindahan pasif melalui perantara makanan maupun minuman. Penelitian sebelumnya menunjukkan bahwa ekstrak daun ubi kayu dapat menghambat pertumbuhan bakteri gram positif dan gram negatif. Tujuan penelitian ini adalah mengetahui efek antibakteri ekstrak daun ubi kayu terhadap pertumbuhan bakteri Escherichia coli. Ekstrak ubi kayu dibuat dalam tiga konsentrasi (20%, 40%, 60%) yang diuji daya hambatnya. Penelitian ini menggunakan bakteri Escherichia coli yang dibiakkan dengan media EMBA (Eosin Meythelen Blue Agar) dengan metode paper disk. Didapatkan adanya zona bening disekitar paperdisk yang mengandung ektrak daun ubi kayu. Simpulan penelitian ini adalah ekstrak ubi kayu (Manihot esculenta Crans) memiliki aktivitas antibakteri terhadap bakteri Eschericia coli. Konsentrasi paling efektif dalam menghambat bakteri adalah 60%.   &nbsp

Pied flycatcher nestlings incur immunological but not growth begging costs

Many theoretical models on the evolution of nestling begging assume this behavior is costly, so that only nestlings in real need of food would profit from giving intensive signals to parents. However, evidence accumulated for the last 2 decades is either contradictory (growth costs) or scant (immunological cost). Here, we experimentally test the existence of both costs in pied flycatcher (Ficedula hypoleuca) nestlings, a species in which parents appropriately respond to honest begging signals. Nestlings were paired by nest of origin and similar body mass. In each pair, a nestling was forced to beg for 51s/meal, whereas the other begged for only 3.4s/meal, both receiving the same amount of food. Simultaneously, the nestling immune response to an antigen (phytohemagglutinin) was measured. Experimental nestlings showed reduced immunocompetence compared with control chicks, which in this species could be regarded as a genuine direct cost. High-begging nestlings also gained less mass during the daylight activity hours. However, they lost less mass while resting at night, resulting in similar mass gains for both groups across the whole daily cycle. This suggests that negative effects of excess begging on mass gain can be compensated for by nestlings, thus avoiding the negative fitness consequences (i.e., cost) of a retarded growth. Mixed results found in previous studies may reflect interspecific differences in compensatory changes in mass gain. But if such differences do not map into fitness consequences, they may be of little help to answer the question of whether begging entails direct growth costs.Peer reviewe