Quinoxaline: Z′ = 1 form

A new Z′ = 1 crystal structure of quinoxaline (or 1,4-diaza­naphthalene), C8H6N2, with one-fifth the volume of the earlier known Z′ = 5 structure was obtained by means of an in situ cryocrystallization technique

N-(2-Amino-3,5-dibromo­benz­yl)-N-methyl­cyclo­hexan-1-aminium p-toluenesulfonate

The title compound, C14H21Br2N2 +·C7H7O3S−, features a salt of protonated bromhexine, a pharmaceutical used in the treatment of respiratory disorders, and the p-toluenesulfonate anion. The crystal packing is stabilized by inter­molecular N—H⋯O, N—H⋯Br and C—H⋯O hydrogen bonds

3-(2-Bromo­acet­yl)-6-fluoro-2H-chromen-2-one

The non-H atoms of the title compound, C11H6BrFO3, are essentially coplanar (r.m.s. deviation for all non-H atoms = 0.074 Å). In the crystal, the molecules are linked by C—H⋯O and C—H⋯Br inter­actions

Elimination of visceral leishmaniasis in the Indian subcontinent: a comparison of predictions from three transmission models.

We present three transmission models of visceral leishmaniasis (VL) in the Indian subcontinent (ISC) with structural differences regarding the disease stage that provides the main contribution to transmission, including models with a prominent role of asymptomatic infection, and fit them to recent case data from 8 endemic districts in Bihar, India. Following a geographical cross-validation of the models, we compare their predictions for achieving the WHO VL elimination targets with ongoing treatment and vector control strategies. All the transmission models suggest that the WHO elimination target (<1 new VL case per 10,000 capita per year at sub-district level) is likely to be met in Bihar, India, before or close to 2020 in sub-districts with a pre-control incidence of 10 VL cases per 10,000 people per year or less, when current intervention levels (60% coverage of indoor residual spraying (IRS) of insecticide and a delay of 40days from onset of symptoms to treatment (OT)) are maintained, given the accuracy and generalizability of the existing data regarding incidence and IRS coverage. In settings with a pre-control endemicity level of 5/10,000, increasing the effective IRS coverage from 60 to 80% is predicted to lead to elimination of VL 1-3 years earlier (depending on the particular model), and decreasing OT from 40 to 20days to bring elimination forward by approximately 1year. However, in all instances the models suggest that L. donovani transmission will continue after 2020 and thus that surveillance and control measures need to remain in place until the longer-term aim of breaking transmission is achieved

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Impact of energy quantisation in single electron transistor island on hybrid complementary metal oxide semiconductor-single electron transistor integrated circuits

For the first time, the impact of energy quantisation in single electron transistor (SET) island on the performance of hybrid complementary metal oxide semiconductor (CMOS)-SET transistor circuits has been studied. It has been shown through simple analytical models that energy quantisation primarily increases the Coulomb Blockade area and Coulomb Blockade oscillation periodicity of the SET device and thus influences the performance of hybrid CMOS-SET circuits. A novel computer aided design (CAD) framework has been developed for hybrid CMOS-SET co-simulation, which uses Monte Carlo (MC) simulator for SET devices along with conventional SPICE for metal oxide semiconductor devices. Using this co-simulation framework, the effects of energy quantisation have been studied for some hybrid circuits, namely, SETMOS, multiband voltage filter and multiple valued logic circuits. Although energy quantisation immensely deteriorates the performance of the hybrid circuits, it has been shown that the performance degradation because of energy quantisation can be compensated by properly tuning the bias current of the current-biased SET devices within the hybrid CMOS-SET circuits. Although this study is primarily done by exhaustive MC simulation, effort has also been put to develop first-order compact model for SET that includes energy quantisation effects. Finally, it has been demonstrated that one can predict the SET behaviour under energy quantisation with reasonable accuracy by slightly modifying the existing SET compact models that are valid for metallic devices having continuous energy states

A Device to Crystallize Organic Solids: Structure of Ciprofloxacin, Midazolam, and Ofloxacin as Targets

The crystal structure determination of the anhydrous form of any organic compound has been a challenge because of solvent incorporation during crystallization. A device to grow anhydrous forms of low melting organic solids based on vaporization and condensation by a gradient cooling technique has been designed. Its utility has been evaluated by growing anhydrous forms of ciprofloxacin, midazolam, and ofloxacin. Ciprofloxacin crystallizes in triclinic P (1) over bar, midazolam in monoclinic P2(1)/n, and ofloxacin in the C2/c space group. Comparative studies on the conformational features with solvated structure show no significant variation in the aromatic moieties

Structural and photocatalytic activity of lanthanide (Ce, Pr, and Nd) molybdovanadates

Lanthanide (Ce, Pr, and Nd) molybdovanadates were synthesized by the solid-state method. These compounds crystallize in the tetragonal space group I41/amd with a = b = 7.3750 (4) and c = 6.4867 (4) &#197; and Z = 4. The crystal structure has been analyzed by FTIR, UV-visible spectroscopy, and powder X-ray diffraction. Particle sizes are in the range of 300-400 nm as observed by scanning electron microscopy. Energy-dispersive X-ray analysis suggests the formation of Ln0.95Mo0.15V0.85O4 (Ln = Ce, Pr, and Nd) and the Rietveld refinements of the powder X-ray data substantiate this observation. Thermal analysis of these solids shows stability of the phase up to 800 &#176;C. These materials were investigated for photocatalytic activity by degrading different dyes such as methylene blue(MB), orange G (OG), Rhodamine B (RB), Rhodamine Blue (RBL) Alizarine Red S (ARS), and Remazol brilliant blue (RBBR) under solar and UV irradiation since they exhibited lower band gaps. The degradation rates for all the dyes show enhancement as compared to the commercial titania catalyst, Degussa P-25, both in UV and sunlight. These compounds degrade chlorinated phenols much faster than titania, which indicates selectivity toward chloro substitution

Synthesis, Characterization and Photocatalytic Activity of Lanthanide (Ce, Pr and Nd) Orthovanadates

A new approach to the synthesis of the lanthanide orthovanadates $CeVO_4, PrVO_4, and NdVO_4$ is proposed. These compounds exhibit a tetragonal zircon structure, crystallizing in the space group $I4_1/amd$ with a=7.3733(4) Å, c=6.4909(4) Å, and Z=4. The crystal structure has been analyzed by powder X-ray diffraction and FTIR and UV-visible spectroscopies. Particle sizes were found to be in the range of 200-300 nm as seen by scanning electron microscopy, and energy-dispersive X-ray analysis indicated the formation of $LnVO_4$. Thermal analysis of these solids indicated stability of the phase to 1000 °C. The photocatalytic activity of these compounds was investigated for the first time by the degradation of methylene blue. The degradation rates were similar for all compounds and comparable to that of commercial Degussa titania

Structural and Photocatalytic Activity of Lanthanide (Ce, Pr, and Nd) Molybdovanadates

Lanthanide (Ce, Pr, and Nd) molybdovanadates were synthesized by the solid-state method. These compounds crystallize in the tetragonal space group $I4_1/amd$ with a = b = 7.3750 (4) and c = 6.4867 (4)\AA and Z = 4. The crystal structure has been analyzed by FTIR, UV-visible spectroscopy, and powder X-ray diffraction. Particle sizes are in the range of 300-400 nm as observed by scanning electron microscopy. Energy-dispersive X-ray analysis suggests the formation of $Ln_{0.95}Mo_{0.15}V_{0.85}O_4$ (Ln = Ce, Pr, and Nd) and the Rietveld refinements of the powder X-ray data substantiate this observation. Thermal analysis of these solids shows stability of the phase up to $800^o C$. These materials were investigated for photocatalytic activity by degrading different dyes such as methylene blue(MB), orange G (OG), Rhodamine B (RB), Rhodamine Blue (RBL) Alizarine Red S (ARS), and Remazol brilliant blue (RBBR) under solar and UV irradiation since they exhibited lower band gaps. The degradation rates for all the dyes show enhancement as compared to the commercial titania catalyst, Degussa P-25, both in UV and sunlight. These compounds degrade chlorinated phenols much faster than titania, which indicates selectivity toward chloro substitution