666 research outputs found

    Thick Walled Multiple Opening Reinforced Concrete Conduits

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    The Department of The Army Corps of Engineers, Engineering Division, Civil Works, Contract No. DACW-73-70-C-003

    Citrate and malonate increase microbial activity and alter microbial community composition in uncontaminated and diesel-contaminated soil microcosms

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    Petroleum hydrocarbons (PHCs) are among the most prevalent sources of environmental contamination. It has been hypothesized that plant root exudation of low molecular weight organic acid anions (carboxylates) may aid degradation of PHCs by stimulating heterotrophic microbial activity. To test their potential implication for bioremediation, we applied two commonly exuded carboxylates (citrate and malonate) to uncontaminated and diesel-contaminated microcosms (10 000 mg kg−1; aged 40 days) and determined their impact on the microbial community and PHC degradation. Every 48 h for 18 days, soil received 5 ”mol g−1 of (i) citrate, (ii) malonate, (iii) citrate + malonate or (iv) water. Microbial activity was measured daily as the flux of CO2. After 18 days, changes in the microbial community were assessed by a community-level physiological profile (CLPP) and 16S rRNA bacterial community profiles determined by denaturing gradient gel electrophoresis (DGGE). Saturated PHCs remaining in the soil were assessed by gas chromatography–mass spectrometry (GC-MS). Cumulative soil respiration increased 4- to 6-fold with the addition of carboxylates, while diesel contamination resulted in a small, but similar, increase across all carboxylate treatments. The addition of carboxylates resulted in distinct changes to the microbial community in both contaminated and uncontaminated soils but only a small increase in the biodegradation of saturated PHCs as measured by the n-C17 : pristane biomarker. We conclude that while the addition of citrate and malonate had little direct effect on the biodegradation of saturated hydrocarbons present in diesel, their effect on the microbial community leads us to suggest further studies using a variety of soils and organic acids, and linked to in situ studies of plants, to investigate the role of carboxylates in microbial community dynamics

    Low molecular weight organic anions (carboxylates) increase microbial activity and alter microbial community composition in uncontaminated and diesel contaminated soil

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    Petroleum hydrocarbons (PHCs) are among the most prevalent sources of environmental contamination. It has been hypothesized that plant root exudation of low molecular weight organic acid anions (carboxylates) may aid degradation of PHCs by stimulating heterotrophic microbial activity. We, therefore, applied two commonly-exuded carboxylates (citrate and malonate) to uncontaminated and diesel contaminated microcosms (10,000 mg kg–1; aged 40 days) to determine their impact on the microbial community and PHC degradation. Every 48 hours for 18 days, soil received 5 ÎŒmol g–1 of i) citrate, ii) malonate, iii) citrate + malonate or iv) water. Microbial activity was measured daily as the flux of CO2. After 18 days, changes in the microbial community were assessed by community level physiological profiles and 16S rRNA bacterial community profiles determined by denaturing gradient gel electrophoresis. Saturated PHCs remaining in the soil were assessed by GCMS. Cumulative soil respiration increased four- to six-fold with the addition of carboxylates, while diesel contamination resulted in a small, but similar, increase across all carboxylate treatments. The addition of carboxylates resulted in distinct changes to the microbial community, but only a small decrease in the n-C17: pristane biomarker. We conclude that carboxylate addition can increase microbial activity and modify the microbial community in both uncontaminated and diesel-contaminated soils. The impact of these changes on PHC biodegradation and rhizosphere processes, more generally, merits further research

    Efektivitas E-Tilang dalam Penanggulangan Pelanggaran Lalu Lintas (Studi Kasus di Polres Karanganyar)

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    Traffic violations by road users are an on going problem as long as there is no legal awareness instilled by road users because traffic violations are considered a normal culture in society. Lack of discipline as road users and lack of public awareness of the law are the main causes of traffic violations. This study uses an empirical juridical approach whose main data source is primary data in the form of interviews and legal documents. From this study, it was found that the effectiveness of the application of E-Ticket to traffic customers by the Karanganyar Police stated that the application was quite effective. Because it eliminates the practice of extortion that has been carried out by unscrupulous persons to traffic violators, in this case minimizing the encounter between unscrupulous persons and traffic violators because all the systems are based online. The weakness that is a factor constraining the implementation of E-Tilang is the limited installation of CCTV in the entire Karanganyar area so that the police have not been able to fully cover traffic violations. The advantages of e-ticket sanctions in creating traffic order are that people are more careful when driving and who definitely obey traffic rules

    Primordial nucleosynthesis and hadronic decay of a massive particle with a relatively short lifetime

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    In this paper we consider the effects on big bang nucleosynthesis (BBN) of the hadronic decay of a long-lived massive particle. If high-energy hadrons are emitted near the BBN epoch (t∌10−2t \sim 10^{-2} -- 102sec⁥10^2 \sec), they extraordinarily inter-convert the background nucleons each other even after the freeze-out time of the neutron to proton ratio. Then, produced light element abundances are changed, and that may result in a significant discrepancy between standard BBN and observations. Especially on the theoretical side, now we can obtain a lot of experimental data of hadrons and simulate the hadronic decay process executing the numerical code of the hadron fragmentation even in the high energy region where we have no experimental data. Using the light element abundances computed in the hadron-injection scenario, we derive a constraint on properties of such a particle by comparing our theoretical results with observations.Comment: 33 pages, 14 postscript figures, reference added, typo corrected, to appear in Phys. Rev.

    BBN and the Primordial Abundances

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    The relic abundances of the light elements synthesized during the first few minutes of the evolution of the Universe provide unique probes of cosmology and the building blocks for stellar and galactic chemical evolution, while also enabling constraints on the baryon (nucleon) density and on models of particle physics beyond the standard model. Recent WMAP analyses of the CBR temperature fluctuation spectrum, combined with other, relevant, observational data, has yielded very tight constraints on the baryon density, permitting a detailed, quantitative confrontation of the predictions of Big Bang Nucleosynthesis with the post-BBN abundances inferred from observational data. The current status of this comparison is presented, with an emphasis on the challenges to astronomy, astrophysics, particle physics, and cosmology it identifies.Comment: To appear in the Proceedings of the ESO/Arcetri Workshop on "Chemical Abundances and Mixing in Stars in the Milky Way and its Satellites", eds., L. Pasquini and S. Randich (Springer-Verlag Series, "ESO Astrophysics Symposia"

    Inhomogeneous Big Bang Nucleosynthesis and Mutual Ion Diffusion

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    We present a study of inhomogeneous big bang nucleosynthesis with emphasis on transport phenomena. We combine a hydrodynamic treatment to a nuclear reaction network and compute the light element abundances for a range of inhomogeneity parameters. We find that shortly after annihilation of electron-positron pairs, Thomson scattering on background photons prevents the diffusion of the remaining electrons. Protons and multiply charged ions then tend to diffuse into opposite directions so that no net charge is carried. Ions with Z>1 get enriched in the overdense regions, while protons diffuse out into regions of lower density. This leads to a second burst of nucleosynthesis in the overdense regions at T<20 keV, leading to enhanched destruction of deuterium and lithium. We find a region in the parameter space at 2.1E-10<eta<5.2E-10 where constraints 7Li/H<10^{-9.7} and D/H<10^{-4.4} are satisfied simultaneously.Comment: 9 pages, minor changes to match the PRD versio

    Analisis Pelaksanaan Pemberian Pembiayaan Berbasis Teknologi Informasi Oleh Financial Technology

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    The fintech transactions that have been carried out so far in Indonesia have raised many important issues, namely the misuse of the personal data of fintech users, where many cases of illegal online loans have arisen accompanied by inappropriate threats from fintech agents that create public trust in platforms fintech is decreasing. Many adverse impacts and risks are felt by the community due to the use of this illegal fintech platform. The role and function of OJK supervision is absolutely necessary in order to prevent negative impacts caused by illegal fintech and legal fintech with improper billing techniques that spread and harm the community. The purpose of this paper is to examine the impact of the implementation of information technology-based crediting by fintech to the public and business actors and examine the form of supervision of the Financial Services Authority on protecting the personal data of the public and business users of fintech users. In this study the authors used an empirical approach. Referred to as empirical legal research or also referred to as non-doctrinal research, by examining primary data in the field by examining the impact of the implementation of technology-based crediting and the form of supervision of the Financial Services Authority on protecting personal data of the public and business users of fintech users. In this study the authors took data with fintech users and victims of illegal fintech in the Surakarta region and the Surakarta OJK. The results of the study in this discussion mentioned that many cases of illegal fintech targeting the lower middle class community. Fintech financing has been misused its function and purpose from initially providing financing towards falsification and even misuse of personal data. OJK is still waiting for the step of the government and lawmakers in formalizing the Personal Data Protection Bill. Related to the temporary legal umbrella that has been prepared by OJK in the context of oversight of fintech has been regulated in OJK Regulation No.13 / POJK.02 / 2018 concerning Digital Financial Innovation in the Financial Services Sector which contains important points related to the regulation of fintech in Indonesia, in among others, that fintech must meet the scope and criteria of the IKD, arrangements that fintech must take the form of a PT or cooperative legal entity and arrangements regarding Regulatory Sandbox. Even more important is related to the protection and confidentiality of borrower or consumer data as regulated in Article 30 paragraph (2) whereby the fintech party must obtain consent from the user, convey limits and changes if there is a change in the use of data and information to the user. All of this has been stipulated in POJK and there is no government regulation that clearly stipulates fintech restrictions on users' personal data in the form of the Personal Data Protection Act

    Solar Neutrino Constraints on the BBN Production of Li

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    Using the recent WMAP determination of the baryon-to-photon ratio, 10^{10} \eta = 6.14 to within a few percent, big bang nucleosynthesis (BBN) calculations can make relatively accurate predictions of the abundances of the light element isotopes which can be tested against observational abundance determinations. At this value of \eta, the Li7 abundance is predicted to be significantly higher than that observed in low metallicity halo dwarf stars. Among the possible resolutions to this discrepancy are 1) Li7 depletion in the atmosphere of stars; 2) systematic errors originating from the choice of stellar parameters - most notably the surface temperature; and 3) systematic errors in the nuclear cross sections used in the nucleosynthesis calculations. Here, we explore the last possibility, and focus on possible systematic errors in the He3(\alpha,\gamma)Be7 reaction, which is the only important Li7 production channel in BBN. The absolute value of the cross section for this key reaction is known relatively poorly both experimentally and theoretically. The agreement between the standard solar model and solar neutrino data thus provides additional constraints on variations in the cross section (S_{34}). Using the standard solar model of Bahcall, and recent solar neutrino data, we can exclude systematic S_{34} variations of the magnitude needed to resolve the BBN Li7 problem at > 95% CL. Additional laboratory data on He3(\alpha,\gamma)Be7 will sharpen our understanding of both BBN and solar neutrinos, particularly if care is taken in determining the absolute cross section and its uncertainties. Nevertheless, it already seems that this ``nuclear fix'' to the Li7 BBN problem is unlikely; other possible solutions are briefly discussed.Comment: 21 pages, 3 ps figure

    SuperWIMP Dark Matter Signals from the Early Universe

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    Cold dark matter may be made of superweakly-interacting massive particles, superWIMPs, that naturally inherit the desired relic density from late decays of metastable WIMPs. Well-motivated examples are weak-scale gravitinos in supergravity and Kaluza-Klein gravitons from extra dimensions. These particles are impossible to detect in all dark matter experiments. We find, however, that superWIMP dark matter may be discovered through cosmological signatures from the early universe. In particular, superWIMP dark matter has observable consequences for Big Bang nucleosynthesis and the cosmic microwave background (CMB), and may explain the observed underabundance of 7Li without upsetting the concordance between deuterium and CMB baryometers. We discuss implications for future probes of CMB black body distortions and collider searches for new particles. In the course of this study, we also present a model-independent analysis of entropy production from late-decaying particles in light of WMAP data.Comment: 19 pages, 5 figures, typos correcte
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