Layering in the Ising model

We consider the three-dimensional Ising model in a half-space with a boundary field (no bulk field). We compute the low-temperature expansion of layering transition lines

A lattice model for the line tension of a sessile drop

Within a semi--infinite thre--dimensional lattice gas model describing the coexistence of two phases on a substrate, we study, by cluster expansion techniques, the free energy (line tension) associated with the contact line between the two phases and the substrate. We show that this line tension, is given at low temperature by a convergent series whose leading term is negative, and equals 0 at zero temperature

Djelovanje per- i polifluoroalkilnih tvari na okolišne i ljudske mikroorganizme i njihov potencijal za bioremedijaciju

Utilised in a variety of consumer products, per- and polyfluoroalkyl substances (PFAS) are major environmental contaminants that accumulate in living organisms due to their highly hydrophobic, lipophobic, heat-resistant, and non-biodegradable properties. This review summarizes their effects on microbial populations in soils, aquatic and biogeochemical systems, and the human microbiome. Specific microbes are insensitive to and even thrive with PFAS contamination, such as Escherichia coli and the Proteobacteria in soil and aquatic environments, while some bacterial species, such as Actinobacteria and Chloroflexi, are sensitive and drop in population. Some bacterial species, in turn, have shown success in PFAS bioremediation, such as Acidimicrobium sp. and Pseudomonas parafulva.Budući da se koriste u izradi raznih potrošačkih proizvoda, per- i polifluoroalkilne tvari (engl. per- and polyfluoroalkyl substances, krat. PFAS) veliki su zagađivači okoliša koji se nakupljaju u živim organizmima zbog svoje izrazite hidrofobičnosti, lipofobičnosti, otpornosti na topline i biološke nerazgradljivosti. Ovaj članak donosi sažeti pregled njihova djelovanja na populacije mikroba u tlu, vodnim i biogeokemijskim sustavima te na humanom mikrobiomu. Pojedini su mikrobi neosjetljivi na zagađenje PFAS-om, čak i napreduju, poput bakterije Escherichia coli i proteobakterija u tlu i vodi, a osjetljive su pojedine bakterijske vrste, poput rodova Actinobacteria i Chloroflexi, pa im se smanjuje populacija u takvom okružju. Neke su se, pak, bakterije pokazale uspješnima u bioremedijaciji, poput vrsta Acidimicrobium sp. i Pseudomonas parafulva

Pemberian Motivasi Berwirausaha Online Kepada Siswa-siswi SMA Perguruan Advent Bogor

Toko online adalah suatu tempat kita bisa menjual, memajang, dan memperlihatkan barang dagangan diinternet. Konsep Toko online ini memungkinkan kita selaku konsumen membeli barang sesuai dengankebutuhan tanpa perlu datang ke tempat penjualnya langsung, disamping itu para pelajar diharuskan untuk dapatmengikuti perkembangan zaman dimana segala sesuatu yang rumit sudah berubah menjadi instan. Tokopediamerupakan salah satu bentuk toko online yang berhasil menarik banyak penjual dan pembeli untuk bertransaksiTujuan dari pelatihan ini adalah untuk memotivasi para pelajar untuk memahami peluang berjualan online danmampu mengimplementasikan dalam dunia nyata. Metode dilakukan dengan ceramah terhadap peserta di kelasatau ruangan tertentu dan menyampaikan materi serta tindakan nyata yang telah dilaksanakan sebelumnya dalamdunia/bisnis toko online

Systematic first-principles study of impurity hybridization in NiAl

We have performed a systematic first-principles computational study of the effects of impurity atoms (boron, carbon, nitrogen, oxygen, silicon, phosporus, and sulfur) on the orbital hybridization and bonding properties in the intermetallic alloy NiAl using a full-potential linear muffin-tin orbital method. The matrix elements in momentum space were used to calculate real-space properties: onsite parameters, partial densities of states, and local charges. In impurity atoms that are empirically known to be embrittler (N and O) we found that the 2s orbital is bound to the impurity and therefore does not participate in the covalent bonding. In contrast, the corresponding 2s orbital is found to be delocalized in the cohesion enhancers (B and C). Each of these impurity atoms is found to acquire a net negative local charge in NiAl irrespective of whether they sit in the Ni or Al site. The embrittler therefore reduces the total number of electrons available for covalent bonding by removing some of the electrons from the neighboring Ni or Al atoms and localizing them at the impurity site. We show that these correlations also hold for silicon, phosporus, and sulfur.Comment: Revtex, 8 pages, 7 eps figures, to appear in Phys. Rev.

Acoustic and perceptual evaluation of Mandarin tone productions before and after perceptual training

This is the publisher's version, also available electronically from http://scitation.aip.org/content/asa/journal/jasa/113/2/10.1121/1.1531176.Training American listeners to perceive Mandarin tones has been shown to be effective, with trainees’ identification improving by 21%. Improvement also generalized to new stimuli and new talkers, and was retained when tested six months after training [Y. Wang et al., J. Acoust. Soc. Am. 106, 3649–3658 (1999)]. The present study investigates whether the tonecontrasts gained perceptually transferred to production. Before their perception pretest and after their post-test, the trainees were recorded producing a list of Mandarin words. Their productions were first judged by native Mandarin listeners in an identification task. Identification of trainees’ post-test tone productions improved by 18% relative to their pretest productions, indicating significant tone production improvement after perceptual training. Acoustic analyses of the pre- and post-training productions further reveal the nature of the improvement, showing that post-training tone contours approximate native norms to a greater degree than pretraining tone contours. Furthermore, pitch height and pitch contour are not mastered in parallel, with the former being more resistant to improvement than the latter. These results are discussed in terms of the relationship between non-native tone perception and production as well as learning at the suprasegmental level

The repulsive lattice gas, the independent-set polynomial, and the Lov\'asz local lemma

We elucidate the close connection between the repulsive lattice gas in equilibrium statistical mechanics and the Lovasz local lemma in probabilistic combinatorics. We show that the conclusion of the Lovasz local lemma holds for dependency graph G and probabilities {p_x} if and only if the independent-set polynomial for G is nonvanishing in the polydisc of radii {p_x}. Furthermore, we show that the usual proof of the Lovasz local lemma -- which provides a sufficient condition for this to occur -- corresponds to a simple inductive argument for the nonvanishing of the independent-set polynomial in a polydisc, which was discovered implicitly by Shearer and explicitly by Dobrushin. We also present some refinements and extensions of both arguments, including a generalization of the Lovasz local lemma that allows for "soft" dependencies. In addition, we prove some general properties of the partition function of a repulsive lattice gas, most of which are consequences of the alternating-sign property for the Mayer coefficients. We conclude with a brief discussion of the repulsive lattice gas on countably infinite graphs.Comment: LaTex2e, 97 pages. Version 2 makes slight changes to improve clarity. To be published in J. Stat. Phy

Salinity tolerance of diapausing eggs of freshwater zooplankton

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73091/1/j.1365-2427.2004.01185.x.pd