Stability of the human faecal microbiome in a cohort of adult men

Characterizing the stability of the gut microbiome is important to exploit it as a therapeutic target and diagnostic biomarker. We metagenomically and metatranscriptomically sequenced the faecal microbiomes of 308 participants in the Health Professionals Follow-Up Study. Participants provided four stool samples—one pair collected 24–72 h apart and a second pair ~6 months later. Within-person taxonomic and functional variation was consistently lower than between-person variation over time. In contrast, metatranscriptomic profiles were comparably variable within and between subjects due to higher within-subject longitudinal variation. Metagenomic instability accounted for ~74% of corresponding metatranscriptomic instability. The rest was probably attributable to sources such as regulation. Among the pathways that were differentially regulated, most were consistently over- or under-transcribed at each time point. Together, these results suggest that a single measurement of the faecal microbiome can provide long-term information regarding organismal composition and functional potential, but repeated or short-term measures may be necessary for dynamic features identified by metatranscriptomics

The correction method of transmission complex coefficients code matrix for AESA TRM

Приемопередающие модулей (ППМ) используемые в современных радарах на базе активных фазированных антенных решеток для дистанционного зондирования земли (ДЗЗ) имеют в своем составе дискретные фазовращатели и аттенюаторы. Описывается метод коррекции матрицы кодов измеренных комплексных коэффициентов передачи (ККП) ППМ для оптимального соответствия идеальным значениям. Приведены значения ошибок, которые являются результатом несовершенства состояния ККП для пары 6-битных фазовращателя и аттенюатора, до и после использования метода.A large majority of modern Transmit-Receive modules (TRM) for AESA radar uses phase discrete shifters and attenuators. The method of matrix code correction of measured TRM's complex transmission coefficient (CTC) for optimal correspondence to ideal one is described. Errors which are the result of imperfection complex state of a pair 6-bit phase shifter and attenuator are presented before and after using the method

A good presentation of (-2,3,2s+1)-type Pretzel knot group and R-covered foliation

Let K_s be a (-2,3,2s+1)-type Pretzel knot (s >= 3) and E(K_s)(p/q) be a closed manifold obtained by Dehn surgery along K_s with a slope p/q. We prove that if q>0, p/q >= 4s+7 and p is odd, then E(K_s)(p/q) cannot contain an R-covered foliation. This result is an extended theorem of a part of works of Jinha Jun for (-2,3,7)-Pretzel knot.Comment: 18 page

Optically trapped bacteria pairs reveal discrete motile response to control aggregation upon cell–cell approach

Aggregation of bacteria plays a key role in the formation of many biofilms. The critical first step is cell–cell approach, and yet the ability of bacteria to control the likelihood of aggregation during this primary phase is unknown. Here, we use optical tweezers to measure the force between isolated Bacillus subtilis cells during approach. As we move the bacteria towards each other, cell motility (bacterial swimming) initiates the generation of repulsive forces at bacterial separations of ~3 μm. Moreover, the motile response displays spatial sensitivity with greater cell–cell repulsion evident as inter-bacterial distances decrease. To examine the environmental influence on the inter-bacterial forces, we perform the experiment with bacteria suspended in Tryptic Soy Broth, NaCl solution and deionised water. Our experiments demonstrate that repulsive forces are strongest in systems that inhibit biofilm formation (Tryptic Soy Broth), while attractive forces are weak and rare, even in systems where biofilms develop (NaCl solution). These results reveal that bacteria are able to control the likelihood of aggregation during the approach phase through a discretely modulated motile response. Clearly, the force-generating motility we observe during approach promotes biofilm prevention, rather than biofilm formation

Vortices, circumfluence, symmetry groups and Darboux transformations of the (2+1)-dimensional Euler equation

The Euler equation (EE) is one of the basic equations in many physical fields such as fluids, plasmas, condensed matter, astrophysics, oceanic and atmospheric dynamics. A symmetry group theorem of the (2+1)-dimensional EE is obtained via a simple direct method which is thus utilized to find \em exact analytical \rm vortex and circumfluence solutions. A weak Darboux transformation theorem of the (2+1)-dimensional EE can be obtained for \em arbitrary spectral parameter \rm from the general symmetry group theorem. \rm Possible applications of the vortex and circumfluence solutions to tropical cyclones, especially Hurricane Katrina 2005, are demonstrated.Comment: 25 pages, 9 figure

TELAAH KRITIS MENGENAI FINANCIAL PERFORMANCE PERUSAHAAN SAAT SEBELUM DAN SESUDAH MERGER & AKUISISI PADA INDUSTRI TELEKOMUNIKASI YANG TERDAFTAR DI BURSA EFEK INDONESIA PERIODE 2002-2009

Penelitian ini bertujuan untuk menelaah adanya perbedaan performa finansial sebelum dan sesudah merger & akusisi pada perusahaan telekomunikasi yang terdaftar di Bursa Efek Indonesia. Performa finansial perusahaan telekomunikasi diukur menggunakan rasio-rasio keuangan yaitu: Current Ratio (CR), Total Assets Turnover (TATO), Debt Ratio (DR), Debt to Equity Ratio (DER), Return On Assets (ROA), Operating Profit Margin (OPM), Net Profit Margin (NPM), dan Price to Book Value (PBV). Merger merupakan penggabungan dua perusahaan atau lebih yang kemudian menjadi satu kekuatan untuk memperkuat posisi perusahaan, sedangkan akuisisi merupakan pengambilalihan (take over) sebagian atau keseluruhan saham perusahaan lain sehingga perusahaan pengakuisisi mempunyai hak kontrol atas perusahaan target. Penelitian ini menggunakan pendekatan kuantitatif. Teknik yang digunakan untuk mengumpulkan data dalam penelitian ini adalah teknik dokumentasi. Populasi penelitian ini meliputi perusahaan telekomunikasi yang terdaftar di Bursa Efek Indonesia yang pernah melakukan merger & akuisisi, dan perusahaan tersebut mengumumkan aktivitasnya tersebut pada periode 2002- 2009. Metode pengambilan sampel yang digunakan dalam penelitian ini adalah purposive sampling. Terdapat 3 perusahaan yang masuk dalam kriteria penelitian ini. Metode analisis data yang digunakan untuk menjawab hipotesis 1 sampai 8 (perhitungan rasio-rasio keuangan) digunakan uji normalitas data dan uji beda paired sample t-test. Dari pengujian secara parsial (paired sample t-test) untuk 1 tahun sebelum dengan 1 tahun setelah merger & akuisisi menunjukkan tidak adanya hasil yang signifikan pada rasio keuangan CR, TATO, DR, DER, OPM, NPM, dan PBV. Hanya pada rasio keuangan ROA saja yang menunjukkan hasil yang signifikan. Untuk pengujian 1 tahun sebelum dengan 2 tahun setelah merger & akuisisi menunjukkan tidak adanya hasil yang signifikan pada seluruh rasio keuangan. Hasil tersebut menunjukkan bahwa merger & akuisisi tidak memberikan dampak yang nyata terhadap performa finansial perusahaan telekomunikasi yang terdaftar di Bursa Efek Indonesia. Kata Kunci: Merger & Akuisisi, Performa Finansial, Paired Sample t-tes

On Axially Symmetric Solutions in the Electroweak Theory

We present the general ansatz, the energy density and the Chern-Simons charge for static axially symmetric configurations in the bosonic sector of the electroweak theory. Containing the sphaleron, the multisphalerons and the sphaleron-antisphaleron pair at finite mixing angle, the ansatz further allows the construction of the sphaleron and multisphaleron barriers and of the bisphalerons at finite mixing angle. We conjecture that further solutions exist.Comment: 17 pages, latex, THU-94/0

On the classification of scalar evolutionary integrable equations in 2+12+1 dimensions

We consider evolutionary equations of the form $u_t=F(u, w)$ where $w=D_x^{-1}D_yu$ is the nonlocality, and the right hand side $F$ is polynomial in the derivatives of $u$ and $w$. The recent paper \cite{FMN} provides a complete list of integrable third order equations of this kind. Here we extend the classification to fifth order equations. Besides the known examples of Kadomtsev-Petviashvili (KP), Veselov-Novikov (VN) and Harry Dym (HD) equations, as well as fifth order analogues and modifications thereof, our list contains a number of equations which are apparently new. We conjecture that our examples exhaust the list of scalar polynomial integrable equations with the nonlocality $w$. The classification procedure consists of two steps. First, we classify quasilinear systems which may (potentially) occur as dispersionless limits of integrable scalar evolutionary equations. After that we reconstruct dispersive terms based on the requirement of the inheritance of hydrodynamic reductions of the dispersionless limit by the full dispersive equation

How does prior lucky event affect individual’s risk taking preference?

We conducted a controlled experiment with Philippines domestic helpers and Lingnan undergraduate students to study if prior “lucky” event will increase their risk-taking behaviour. The major finding from our study is that prior lucky events do increase risk-taking behaviour among Philippines domestic helpers but not for students. Our study also found out that there are inconsistent behaviour of interviewees while choosing for options indicating their risk preference and this degree of inconsistency is greater among the Philippines group compared to the students group