Effect of Silene vulgaris and Heavy Metal Pollution on Soil; Microbial Diversity in Long-Term Contaminated Soil

In this study, we analysed the impact of heavy metals and plant rhizodeposition on the structure of indigenous microbial communities in rhizosphere and bulk soil that had been exposed to heavy metals for more than 150 years. Samples of the rhizosphere of Silene vulgaris and non-rhizosphere soils 250 and 450 m from the source of emission that had different metal concentrations were collected for analyses. The results showed that soils were collected 250 m from the smelter had a higher number of Cd-resistant CFU compared with the samples that were collected from 450 m, but no significant differences were observed in the number of total and oligotrophic CFU or the equivalent cell numbers between rhizosphere and non-rhizosphere soils that were taken 250 and 450 m from the emitter. Unweighted pair group method with arithmetic mean (UPGMA) cluster analysis of the denaturing gradient gel electrophoresis (DGGE) profiles, as well as a cluster analysis that was generated on the phospholipid fatty acid (PLFA) profiles, showed that the bacterial community structure of rhizosphere soils depended more on the plant than on the distance and metal concentrations. The sequencing of the 16S rDNA fragments that were excised from the DGGE gel revealed representatives of the phyla Bacteroidetes, Acidobacteria, Gemmatimonadetes, Actinobacteria and Betaproteobacteria in the analysed soil with a predominance of the first three groups. The obtained results demonstrated that the presence of S. vulgaris did not affect the number of CFUs, except for those of Cd-resistant bacteria. However, the presence of S. vulgaris altered the soil bacterial community structure, regardless of the sampling site, which supported the thesis that plants have a higher impact on soil microbial community than metal contamination.Peer reviewe

On Asymptotics of Some Fractional Differential Equations

In this paper we study the large-argument asymptotic behaviour of certain fractional differential equations with Caputo derivatives. We obtain exponential and algebraic asymptotic solutions. The latter, decaying asymptotics differ significantly from the integer-order derivative equations. We verify our theorems numerically and find that our formulas are accurate even for small values of the argument. We analyze the zeros of fractional oscillations and find the approximate formulas for their distribution. Our methods can be used in studying many other fractional equations

Decrypting Local Type Inference

Statically typed languages verify programs at compile-time. As a result many programming mistakes are detected at an early stage of development. A programmer does not have to specify types for every single term manually, however. Many programming languages can reconstruct a termâs type using type inference algorithms. While helpful, programmers often find it hard to comprehend the choice of typing decisions that led to the derived type for a term. A particularly serious consequence is that the reporting of type errors yields cryptic messages and misleading program locations. In this thesis we propose a novel approach to explaining type checking decisions by exploring fragments of type derivation trees. Our approach applies to programming languages that use local type inference: typing decisions are made locally and the type information is only propagated between the adjacent AST nodes. We design an algorithm that backtracks through the nodes of type derivation trees in order to discover the typing decisions that introduce the types for the first time during the type inference process. Our algorithm has two properties: - it is type-driven, meaning that we only visit the nodes and their respective typing decisions if they participated in the inference of a type. - it is autonomous, meaning that it does not require any user-input in its operation. These properties allow us to identify the complete and precise set of locations defining the source of a type; previous work mostly focussed on heuristics or used approximations for locating the cause of an error. Our algorithm is not tied to a particular implementation of a type checker: our type derivation trees can be reconstructed from a pre-existing type checker without modifying its internal logic or affecting its regular compilation times. It therefore readily applies to existing programs: we can not only provide improved feedback for them, we also expose limitations of local type inference algorithms and their implementations, without artificially limiting the language features. We implement our type debugging algorithm on top of Scalaâs type checker. Our analysis applies to a range of erroneous scenarios. It provides better error locations than the standard type error reporter of the Scala compiler. This type debugging analysis is just a starting point from which many interesting and useful applications around type debugging can be built: - we implement an interactive type debugger that guides the users through the decisions of local type inference for erroneous and error-free programs alike. - with precise and minimal source code locations we can also offer surgical-level code modifications that fix for example the limitations of local type inference. - we open the door for programmatically defined, application-specific error feedback or corrections. To the best of our knowledge this thesis is the first to address the problem of type errors for programming languages that use local type inference. Current trends suggest that this scheme is gaining in popularity with mainstream languages other than Scala

Rhizospheric Bacterial Strain Brevibacterium casei MH8a Colonizes Plant Tissues and Enhances Cd, Zn, Cu Phytoextraction by White Mustard

Environmental pollution by heavy metals has become a serious problem in the world. Phytoextraction, which is one of the plant-based technologies, has attracted the most attention for the bioremediation of soils polluted with these contaminants. The aim of this study was to determine whether the multiple-tolerant bacterium. Brevibacterium casei MH8a isolated from the heavy metal-contaminated rhizosphere soil of Sinapis alba L., is able to promote plant growth and enhance Cd, Zn, and Cu uptake by white mustard under laboratory conditions. Additionally, the ability of the rifampicin-resistant spontaneous mutant of MH8a to colonize plant tissues and its mechanisms of plant growth promotion were also examined. In order to assess the ecological consequences of bioaugmentation on autochthonous bacteria, the phospholipid fatty acid (PLFA) analysis was used. The MH8a strain exhibited the ability to produce ammonia, 1-amino-cyclopropane-1-carboxylic acid deaminase, indole 3-acetic acid and HCN but was not able to solubilize inorganic phosphate and produce siderophores. Introduction of MH8a into soil significantly increased S, alba biomass and the accumulation of Cd (208%), Zn (86%), and Cu (39%) in plant shoots in comparison with those grown in non-inoculated soil. Introduced into the soil, MH8a was able to enter the plant and was found in the roots and leaves of inoculated plants thus indicating its endophytic features. PLFA analysis revealed that the MH8a that was introduced into soil had a temporary influence on the structure of the autochthonous bacterial communities. The plant growth-promoting features of the MH8a strain and its ability to enhance the metal uptake by white mustard and its long-term survival in soil as well as its temporary impact on autochthonous microorganisms make the strain a suitable candidate for the promotion of plant growth and the efficiency of phytoextraction.Peer reviewe

Implementing a Type Debugger for Scala

Statically-typed languages offer type systems that are less and less comprehensible for programmers as the language grows in complexity. In this paper, we present a type debugger, a tool that enables analysis of type-related problems as well as exploration of the typechecking process in general. We explain our findings on implementing a lightweight instrumentation mechanism for Scala, as well as guide the reader through some typical debugging scenarios in which one can use our tool. The type debugger visualizes the internals of the typechecker which we believe increases its chances of being a successful educational tool, and which simplifies understanding of statically-typed languages in general

Improving Human-Compiler Interaction Through Customizable Type Feedback

Type errors reported by compilers can sometimes be cryptic, or difficult to understand. In this paper, we propose a type debugging framework that exposes a high-level representation of the typechecking decision-making process that users normally do not have access to in state-of-the-art compilers. This representation makes it easier for non-experts to analyze complex type errors. Our system is implemented by instrumenting the existing Scala typechecker, but without modifying it. We also provide generic search algorithms that can be used as basic building blocks to build a number of systems, from visual type debugging tools to customized error reporting for normal Scala users as well as to users of domain-specific languages. Using our framework, it is possible to overcome well-known limitations of local type inference by providing precise type error messages to mainline Scala users or Scala DSL users alike. In addition, the framework provides better user feedback for non-trivial type errors from existing Scala libraries and DSLs

The abundance of health-associated bacteria is altered in PAH polluted soils-Implications for health in urban areas?

Long-term exposure to polyaromatic hydrocarbons (PAHs) has been connected to chronic human health disorders. It is also well-known that i) PAH contamination alters soil bacterial communities, ii) human microbiome is associated with environmental microbiome, and iii) alteration in the abundance of members in several bacterial phyla is associated with adverse or beneficial human health effects. We hypothesized that soil pollution by PAHs altered soil bacterial communities that had known associations with human health. The rationale behind our study was to increase understanding and potentially facilitate reconsidering factors that lead to health disorders in areas characterized by PAH contamination. Large containers filled with either spruce forest soil, pine forest soil, peat, or glacial sand were left to incubate or contaminated with creosote. Biological degradation of PAHs was monitored using GC-MS, and the bacterial community composition was analyzed using 454 pyrosequencing. Proteobacteria had higher and Actinobacteria and Bacteroidetes had lower relative abundance in creosote contaminated soils than in non-contaminated soils. Earlier studies have demonstrated that an increase in the abundance of Proteobacteria and decreased abundance of the phyla Actinobacteria and Bacteroidetes are particularly associated with adverse health outcomes and immunological disorders. Therefore, we propose that pollution-induced shifts in natural soil bacterial community, like in PAH-polluted areas, can contribute to the prevalence of chronic diseases. We encourage studies that simultaneously address the classic "adverse toxin effect" paradigm and our novel "altered environmental microbiome" hypothesis.Peer reviewe

Pengaruh pemberian hukuman terhadap pembentukan akhlaq peserta didik di SMP Muhammadiyah 1 Sidoarjo

Peserta didik yang nakal disekolah hanya dianggap sebagai pengisi waktu saja dari pada kesepian di rumah tidak ada teman. Peserta didik yang berpendapat demikian akan menjadi penghalang terhadap kemajuan belajar dirinya sendiri mapun teman-temannya. Akibatnya mereka yang melanggar peraturan di sekolah dan mendapat hukuman atau sanksi. Hukuman sendiri di sekolah dibuat bukan sebagai pembalasan, tetapi dibuat untuk memperbaiki peserta didik yang dihukum dan melindungi pesera didik lain dari kesalahan yang sama. Oleh karenanya diperlukan pendidikan yang baik untuk membentuk akhlak siswa, diantaranya melalui penerapan dari hukuman sebagai alat pendidikan agar terdapat efek jera. Penelitian ini dilatar belakangi karena akhlak adalah kunci utama untuk menjadi insan kamil. Permasalahan dalam penelitian ini adalah (1) Bagaimana pemberian Hukuman di SMP Muhammadiyah 1 Sidoarjo? (2) Bagaimana pembentukan Akhlak peserta didik di SMP Muhammadiyah 1 Sidoarjo? (3) Bagaimana pengaruh Pemberian Hukuman terhadap Pembentukan Akhlaq peserta didik di SMP Muhammadiyah 1 Sidoarjo? Instrument pengumpulan data dalam penelitian ini menggunakan teknik observasi. Kuesioner dan Interview sebagai instrumen pengumpulan data primer dan teknik dokumentasi sebagai instrument pengumpulan data sekunder. Sedangkan analisis data menggunakan teknik prosentase untuk data yang bersifat deskriptif dan teknik Regresi Linier untuk data yang bersifat kuantitatif. Hasil penelitian menunjukkan bahwa (1) Pemberian hukuman di SMP Muhammadiyah 1 Sidoarjo tergolong baik. (2) Pembentukan akhlak peserta didik di SMP Muhammadiyah 1 Sidoarjo tergolong baik. (3) Hasil perhitungan Regresi Linier diperoleh angka yang nilainya tersebut menunjukkan lebih besar dari Harga Kritik Regresi Linier baik pada taraf signifikansi 5 % maupun 1 %, berarti hipotesis alternatif (Ha) diterima, dan hipotesis nihil (Ho) ditolak. Kesimpulan bahwa terdapat pengaruh antara variabel Pemberian hukuman terhadap pembentukan akhlak peserta didik di SMP Muhammadiyah 1 Sidoarjo sebesar 5,7 %