Modulation of Amide Bond Rotamers in 5-Acyl-6,7-dihydrothieno[3,2-c]pyridines

2-Substituted <i>N</i>-acyl-piperidine is a widespread and important structural motif, found in approximately 500 currently available structures, and present in nearly 30 pharmaceutically active compounds. Restricted rotation of the acyl substituent in such molecules can give rise to two distinct chemical environments. Here we demonstrate, using NMR studies and density functional theory modeling of the lowest energy structures of 5-acyl-6,7-dihydrothieno­[3,2-<i>c</i>]­pyridine derivatives, that the amide <i>E</i>:<i>Z</i> equilibrium is affected by non-covalent interactions between the amide oxygen and adjacent aromatic protons. Structural predictions were used to design molecules that promote either the <i>E</i>- or <i>Z</i>-amide conformation, enabling preparation of compounds with a tailored conformational ratio, as proven by NMR studies. Analysis of the available X-ray data of a variety of published <i>N</i>-acyl-piperidine-containing compounds further indicates that these molecules are also clustered in the two observed conformations. This finding emphasizes that directed conformational isomerism has significant implications for the design of both small molecules and larger amide-containing molecular architectures

Excited state g-functions from the Truncated Conformal Space

In this paper we consider excited state g-functions, that is, overlaps between boundary states and excited states in boundary conformal field theory. We find a new method to calculate these overlaps numerically using a variation of the truncated conformal space approach. We apply this method to the Lee-Yang model for which the unique boundary perturbation is integrable and for which the TBA system describing the boundary overlaps is known. Using the truncated conformal space approach we obtain numerical results for the ground state and the first three excited states which are in excellent agreement with the TBA results. As a special case we can calculate the standard g-function which is the overlap with the ground state and find that our new method is considerably more accurate than the original method employed by Dorey et al.Comment: 21 pages, 6 figure

Struktur dan Komposisi Fitoplankton di Bagian Hulu Sungai Saluesem, Minahasa, Sulawesi Utara

STRUKTUR DAN KOMPOSISI FITOPLANKTON DI BAGIAN HULU SUNGAI SALUESEM, MINAHASA, SULAWESI UTARA Amanda T.C Nalang1), Herni E.I. Simbala1), Nio Song Ai1), Ratna Siahaan1) ABSTRAK Sungai Saluesem termasuk perairan terbuka yang mengalir (lotik) yang berasal dari Gunung Mahawu, Minahasa dan bermuara ke Teluk Manado yang terletak di Kota Manado, Sulawesi Utara. Hulu sungai merupakan daerah konservasi tanah dan air yang sangat penting dalam mempertahankan kualitas air Sungai Saluesem dari hulu hingga hilir. Kegiatan manusia dari permukiman, pertanian dan peternakan yang terus meningkat di hulu Sungai Saluesem dapat menyebabkan terjadinya penurunan kualitas perairan. Tujuan penelitian adalah menganalisis struktur dan komposisi fitoplankton bagian hulu Sungai Saluesem, Minahasa, Sulawesi Utara. Penelitian dilaksanakan dari Oktober 2014 sampai Desember 2014. Penelitian menggunakan metode purposive random sampling. Pengulangan dilakukan sebanyak 3 kali ulangan di tiap titik pengamatan, dengan demikian terdapat enam titik (2 x 3) pengamatan di hulu.Fitoplankton yang didapatkan di hulu Sungai Saluesem sebanyak 1700 individu dari 32 spesies dan 3 kelas. Kelas fitoplankton yaitu Bacillariophyceae, Chlorophyceae, dan Cyanophyceae. Kepadatan tertinggi berasal dari Kelas Bacillariophyceae 2214 individu/m3 (84%) diikuti Kelas Chlorophyceae 349 individu/m3 (13%) lalu Cyanophyceae 72 individu/m3 (3%). Indeks keanekaragaman di Hulu Sungai Saluesem yaitu 2,92 yang termasuk keanekaragaman sedang. Distribusi Spesies fitoplankton di bagian hulu merata dengan indeks kemerataan (E) yaitu 0,64. Tidak ada spesies fitoplankton yang mendominasi di Hulu Sungai dengan indeks dominansi mendekati nol yaitu 0,18. Kualitas air Sungai Saluesem bagian hulu dikategorikan tercemar ringan dengan indeks H' yaitu 2,92. Sumber pencemaran di lokasi penelitian diduga berasal dari kegiatan rumahtangga (MCK) dan peternakan. Kata Kunci: Sungai Saluesem, Struktur Fitoplankton, Komposisi fitoplankton, Kualitas Air, Sulawesi Utara STRUCTURE AND COMPOSITION OF PHYTOPLANKTON OF UPSTREAM SALUESEUM RIVER, MINAHASA, NORTH SULAWESI ABSTRACT Saluesem River is a lotic ecosystem that started from Mahawu Mountain, Minahasa and to Manado Bay, North Sulawesi. Upstream Salusem River is an important soil and water conservation area for to maintain quality of Salusem River from upstream to downstream. Increasing human activities from settlement, agriculture and animal husbandry can decrease quality of Salusem River. The aim of this research was to analysis phytoplankton structure and composition of upper Salusem River, Minahasa, North Sulawesi. The research was conducted from October 2014 to December 2014. The study applied purposive random sampling method with three repetitions. The number of phytoplanktons were 1700 individuals from 32 species and 3 classes, namely Bacillariophyceae, Chlorophyceae, and Cyanophyceae. The highest density is Bacillariophyceae 2214 ind/m3 (84%) followed by Chlorophyceae 349 ind/m3 (13%) and Cyanophyceae 72 ind/ m3 (3%). The diversity index of Saluesem River phytoplankton is 2.92 categorized into middle diversity. Evenness Index is 0.64 showed equal distribution. There is no dominant species showed by dominance index is 0.18. Based on diversity index H' is 2.92, water quality of Salusem River upstream are categorized into light pollution. Different sources of pollution were household, agriculture, animal husbandary activities

Vortex Core Structure and Dynamics in Layered Superconductors

We investigate the equilibrium and nonequilibrium properties of the core region of vortices in layered superconductors. We discuss the electronic structure of singly and doubly quantized vortices for both s-wave and d-wave pairing symmetry. We consider the intermediate clean regime, where the vortex-core bound states are broadened into resonances with a width comparable to or larger than the quantized energy level spacing, and calculate the response of a vortex core to an {\em a.c.} electromagnetic field for vortices that are pinned to a metallic defect. We concentrate on the case where the vortex motion is nonstationary and can be treated by linear response theory. The response of the order parameter, impurity self energy, induced fields and currents are obtained by a self-consistent calculation of the distribution functions and the excitation spectrum. We then obtain the dynamical conductivity, spatially resolved in the region of the core, for external frequencies in the range, 0.1\Delta < \hbar\omega \lsim 3\Delta. We also calculate the dynamically induced charge distribution in the vicinity of the core. This charge density is related to the nonequilibrium response of the bound states and collective mode, and dominates the electromagnetic response of the vortex core.Comment: Presented at the 2000 Workshop on ``Microscopic Structure and Dynamics of Vortices in Unconventional Superconductors and Superfluids'', held at the Max Planck Institute for the Physics of Complex Systems in Dresden, Germany (28 pages with 15 figures). Alternate version with higher resolution figures: http://snowmass.phys.nwu.edu/~sauls/Eprints/Dresden2000.htm

Contextual, Conceptual, and Procedural Knowledge of Vocational High School Students in Solving Distance Contexts

This study aims to describe the contextual, conceptual, and procedural mathematical knowledge of vocational students in solving mathematical tasks presented in the context of distance. This study used a qualitative approach by focusing on data collection techniques through interviews and observations. Participants involved in this study were 20 students of Vocational High School, Motorcycle engineering and business expertise, in Ciamis, Indonesia. Students solve the mathematical tasks on topics of equality and inequality of absolute values in the context of distance. The analysis is carried out on contextual, conceptual, and procedural knowledge by students. The results show that students who can connect contextual knowledge to their conceptual knowledge successfully solve mathematical tasks. This shows that contextual knowledge has the first role in determining the mathematical concepts needed in solving tasks, which are supported by procedural knowledge that will lead students to get the right solution

Malaria in Sokoto, North Western Nigeria

Malaria remains a major cause of mortality among children under the age of five years; it is endemic throughout Nigeria with seasonal variation in different geographic zones of the country. Malaria prevalence studies had been undertaken in many parts of Nigeria but there is probably no dataavailable from the far North Western region. This research study was undertaken to determine the prevalence, monthly distribution of malaria in Sokoto, North Western Nigeria in order to generate baseline information. A total of 1,297 blood samples were collected by simple random sampling, from patients attending the two health centres over the twelve calendar months. Thick and thin blood films were Giemsa stained and observed for the presence of malaria parasites. A total of 354 (27.29%) werepositive for malaria parasites with the highest prevalence rate being recorded in the month of August with 72 (59.5%) positive cases and the month of March having the least infection rate of 9 (9.18%). Theinfection rate according to gender showed that males had the higher infection rate of 192 (n = 635) or 30.24% than the females who had a total 162 infection (n = 662) or 24.47%. The age group 0 - 5 years hadthe highest infection rate of 123 (43.77%) while the age group 36 - 40 years had the least infection rate of 10 (9.8%). The study has revealed the presence of malaria transmission throughout the year in Sokoto, North Western Nigeria and the infection rate can be considered as moderately high

Cleaning up the cosmological constant

We present a novel idea for screening the vacuum energy contribution to the overall value of the cosmological constant, thereby enabling us to choose the bare value of the vacuum curvature empirically, without any need to worry about the zero-point energy contributions of each particle. The trick is to couple matter to a metric that is really a composite of other fields, with the property that the square-root of its determinant is the integrand of a topological invariant, and/or a total derivative. This ensures that the vacuum energy contribution to the Lagrangian is non-dynamical. We then give an explicit example of a theory with this property that is free from Ostrogradski ghosts, and is consistent with solar system physics and cosmological tests.Comment: 8 pages, typos corrected and more text added, version accepted for publication in JHE

Hydrodynamic assessment of a dual-rotor horizontal axis marine current turbine

© 2018 Authors. The hydrodynamic performance of a dual-rotor horizontal axis marine turbine (HAMCT) is investigated for the power gain in operating the rear rotor without blade-pitch control. This kind of turbine can be advantageous for a rectilinear tidal current of reversing directions, where each rotor blade is optimally fixed-pitched towards its upstream velocity. The blade element momentum (BEM) method is coupled with the Park wake model. A generic three-blade turbine is shown to gain up to 20% in the coefficient of power CPas relative to the front rotor CPwhen operating the rear rotor at the same tip speed ratio (TSR) as the front one, gaining overall CPup to 0.55. Analytic model is derived to backup the estimate of power gain. Plots for turbine performance variation with TSR and profile hydrodynamic efficiency are given, and analysed for lab and small-medium size turbines

On the Relationship Between Ultrasonic and Micro-Structural Properties of Imperfect Interfaces in Layered Solids

The interaction of ultrasonic waves with interfaces formed by two non-conforming, rough surfaces in contact has been the subject of numerous investigations [1–10]. The motivations behind these studies have been various: from the assessment of the real area of contact between two rough surfaces [1], to the modeling of crack closure near the tip of a fatigue crack [4]; from the identification of the nature of interfacial imperfections in kissing and partial bonds [6], to the generation of ultrasonic waves [8]. In most of these studies, the characterization of the interfacial properties has been attempted by studying the reflection of longitudinal and shears waves at normal incidence. Only recently, the problem concerning the interaction of ultrasonic waves with realistic complex systems such as that formed by two neighboring imperfect interfaces has been addressed. Lavrentyev and Rokhlin [9, 10] used ultrasonic spectroscopy to evaluate the interfacial conditions from the spectra of longitudinal and shear waves reflected normally from the interfaces

First-generation black-hole-forming supernovae and the metal abundance pattern of a very iron-poor star

It has been proposed theoretically that the first generation of stars in the Universe (population III) would be as massive as 100 solar masses (100Mo), because of inefficient cooling of the precursor gas clouds. Recently, the most iron-deficient (but still carbon-rich) low-mass star -- HE0107-5240 -- was discovered. If this is a population III that gained its metals (elements heavier than helium) after its formation, it would challenge the theoretical picture of the formation of the first stars. Here we report that the patterns of elemental abundance in HE0107-5240 (and other extremely metal-poor stars) are in good accord with the nucleosynthesis that occurs in stars with masses of 20-130Mo when they become supernovae if, during the explosions, the ejecta undergo substantial mixing and fall-back to form massive black holes. Such supernovae have been observed. The abundance patterns are not, however, consistent with enrichment by supernovae from stars in the range 130-300 Mo. We accordingly infer that the first-generation supernovae came mostly from explosions of ~ 20-130Mo stars; some of these produced iron-poor but carbon- and oxygen-rich ejecta. Low-mass second-generation stars, like HE0107-5240, could form because the carbon and oxygen provided pathways for gas to cool.Comment: To appear in NATURE 422 (2003), 871-873 (issue 24 April 2003); Title and the first paragraph have been changed and other minor corrections have been mad