Tima has a typologically unusual 12-vowel advanced tongue root (ATR) harmony system, contrasting six [+ATR] vowels /i e ɨ ʌ o u/ with six [−ATR] vowels /ɪ ɛ ɘ a ɔ ʊ/. This harmony system provides a test case for generalisations about ATR systems: for example, that [−ATR] is less compatible with higher vowels; that [+ATR] is less compatible with lower vowels and that central vowels are incompatible with [ATR] systems. After showing that all vowels participate fully in ATR harmony, this article presents an acoustic study of the Tima ATR contrast. We show that /ʌ/, the [+ATR] counterpart of /a/, patterns as a mid vowel, and that duration and voice quality differences characterise Tima’s crowded vowel inventory. Though F1 is the primary individual correlate of the ATR contrast, as is true cross-linguistically, a number of measures support voice quality differences as well, as predicted by the Laryngeal Articulator Model account of ATR systems.

Acid-base titrations and attenuated total reflectance-infrared (ATR-IR) spectroscopy of solutions containing Zn(NO3)2 and the herbicide 3-amino-1,2,4-triazole suggested that soluble complexes ZnL2+ and Zn(OH)L+ form, where L represents aminotriazole. Sorption experiments and modeling in systems containing K-saturated Wyoming (SWy-K) montmorillonite suggest that at low concentrations the aminotriazole sorbs primarily in cationic form via an ion-exchange mechanism. Sorption isotherms for aminotriazole are ‘s’-shaped, indicating a co-operative sorption mechanism as the concentration of the molecule increases. At higher concentrations, ATR-IR spectroscopy indicated the presence of cationic and neutral triazole molecules on the surface, while X-ray diffraction data suggest interaction with interlayer regions of the clay. When the concentration of the herbicide was high, initial sorption of aminotriazole cations modified the clay to make the partitioning of neutral molecules to the surface more favorable. Experiments conducted in the presence of Zn(II) indicated that below pH 7, Zn(II) and aminotriazole compete for sorption sites, while above pH 7 the presence of Zn(II) enhances the uptake of aminotriazole. The enhancement was attributed to the formation of an inner-sphere ternary surface complex at hydroxyl sites (SOH) on crystal edges, having the form [(SOZn(OH)L)]0.

Layer charge (LC) is a fundamental property of smectite but its measurement remains challenging and tedious to apply on a high-throughput basis. The present study demonstrates that the position of a sharp, high-energy O—D stretching band of adsorbed D2O (νO—D, at ~2686–2700 cm−1), determined by infrared spectroscopy, correlates with LC and provides a simple method for its measurement. Twenty nine natural dioctahedral smectites and 14 reduced-charge montmorillonites with LC determined previously by different methodologies were saturated with D2O and examined by attenuated total reflectance infrared spectroscopy (ATR-IR). The samples included smectites in Mg, Ca, Na, Li, K, and Cs forms and covered the full range of the smectite LC (0.2 to 0.6 e per formula unit). Statistically significant correlations were found between νO—D and LC values determined with each of the two main methods of LC determination: the structural formula method (R2 = 0.96, σ = 0.02, ~0.2 < LC < 0.6) and the alkylammonium method (R2 = 0.92, σ = 0.01, 0.27 < LC < 0.37). These correlations were based on Li- and Na-saturated smectites, respectively, but other cationic forms can be employed provided that the exchangeable cations are of sufficiently high hydration enthalpy (e.g. Mg2+ or Ca2+, but not K+ or Cs+). The new method is fast, low-cost, implemented easily in laboratories equipped with ATR-FTIR, and applicable to samples as small as ~5 mg.

The strong adsorption to kaolinite of four polyaromatic, cationic dyes (9-aminoacridine, 3,6-diaminoacridine, azure A and safranin O), which adsorb much less to alumina or silica, was investigated by means of acid-base titrations, measurements of adsorption at varying pH and dye concentration, and by ATR-FTIR spectroscopy. The four dyes adsorb to kaolinite to similar extents, with little change over the pH range 3–10, but at higher pH (above the pKas of the dyes) the adsorption of 9-aminoacridine and 3,6-diaminoacridine decreases, that of azure A increases, and that of safranin O stays approximately constant. Although the dyes adsorb to kaolinite much more strongly than metal ions do, titration and spectroscopic data show that there is only limited chemical interaction between the adsorbed dyes and the kaolinite surface. The results indicate that electrostatic interaction between the dye molecules and the kaolinite surface is necessary for adsorption, but that hydrophobic interactions also contribute. It is proposed that the relatively hydrophobic silica faces of kaolinite, which carry low-density permanent negative charge, facilitate aggregation and adsorption of the positively charged, flat, aromatic dye molecules.

An overlap of bands produced by the O−H stretching vibrations of H2O (O–Hw) and structural OH (O−Hs) in smectite hampers the study by infrared spectroscopy (IR) of both their layer and interlayer structure. The present study re-evaluated the D2O saturation of smectite as a tool to enable separation of the overlapping bands at ambient conditions. Real-time monitoring by Attenuated Total Reflectance infrared spectroscopy (ATR-IR) was employed during in situ sample drying and H2O or D2O saturation at ambient temperature. Six dioctahedral and one trioctahedral pure smectites in Ca2+-, Na+-, and Cs+-cationic forms were studied to explore variability in total layer charge, charge location, and interlayer cation. The IR data showed the interlayer O−Dw signature at 2700–2200 cm−1 as a proxy for the O−Hw signature in the 3700–3000 cm−1 region. In addition to the expected liquid-like bands of D2O in the interlayer, these O−Dw spectra exhibited an additional sharp stretching feature in the 2695–2680 cm−1 range. No significant cation dependence of the sharp band position was observed between pairs of Ca- and Na-smectites for relative humidity (RH) between 60 and 80%, despite the large difference in the ionic potential between these interlayer cations. The intensity of the sharp band was found to be almost insensitive to changes in water content within the range 60–80% RH. The sharp band frequency decreased linearly with increasing total charge of the 2:1 layer (and can be used as a proxy for it), but no effect of charge location could be discerned. In agreement with early studies, this band was attributed to D2O located on the surface of the interlayer, pointing one O−D group toward the siloxane surface. Based on its high frequency, this band was indicative of free O−D oscillators, with very little or no involvement in hydrogen bonding (“dangling OD”). By analogy to the spectra of D2O-smectites, the spectrum of H2O-smectites also involves a sharp O−Hw analog at ~3630 cm−1 overlapping with typical OHs bands (e.g. Al2OH). As a result of this overlap, the sharp 3630 cm−1 O−Hw contribution was often missed or attributed solely to O−Hs.

In this paper, we examine the acoustics of vowels in the Imilike [ìmìlìkè] dialect of Igbo (Igboid, Niger-Congo), which has not previously been done. While Standard Igbo has eight vowels, previous auditorily-based research has identified eleven vowels in Imilike. Like Standard Igbo, Imilike contrasts vowels in Advanced/Retracted Tongue Root (ATR vs. RTR). We find that there are eleven vowels, distinguished most reliably by F1, B1, energy (dB) of voiced sound below 500Hz and duration. The results of this study also suggest that RTR vowels in Imilike might involve the laryngeal constriction and movement that accompany pharyngealization. The ATR and RTR schwas have similar phonological distribution and acoustic patterns as the other ATR and RTR vowels in the language.

DNA damage response (DDR) pathway prevents high level endogenous and environmental DNA damage being replicated and passed on to the next generation of cells via an orchestrated and integrated network of cell cycle checkpoint signalling and DNA repair pathways. Depending on the type of damage, and where in the cell cycle it occurs different pathways are involved, with the ATM-CHK2-p53 pathway controlling the G1 checkpoint or ATR-CHK1-Wee1 pathway controlling the S and G2/M checkpoints. Loss of G1 checkpoint control is common in cancer through TP53, ATM mutations, Rb loss or cyclin E overexpression, providing a stronger rationale for targeting the S/G2 checkpoints. This review will focus on the ATM-CHK2-p53-p21 pathway and the ATR-CHK1-WEE1 pathway and ongoing efforts to target these pathways for patient benefit.

A low-cost infrared microscope is evaluated in both transmission and attenuated total internal reflection (ATR) sampling modes. Transmission spectra of 60 to 250 micrometer samples exhibited an excellent signal-to-noise ratio. Signal-to-noise in transmission mode also correlated well with theoretical predictions. The quantitative capability of the microscope was demonstrated by measuring the colorant concentration of red, yellow, and blue polypropylene fibers. These latter measurements were conducted using the ATR sampling mode of the microscope. Colorant concentrations could be measured to 1% by weight, and calibration curves with excellent R2 values were obtained over the dye concentration range of 1 to 10% by weight colorant.

An effective method for detecting and characterizing counterfeit finished dosage forms and packaging materials is described in this study. Using attenuated total internal reflection Fourier transform infrared spectroscopic imaging, suspect tablet coating and core formulations as well as multi-layered foil safety seals, bottle labels, and cigarette tear tapes were analyzed and compared directly with those of a stored authentic product. The approach was effective for obtaining molecular information from structures as small as 6 μm.

Until recently, the analysis of polymer laminates using infrared microspectroscopy involved the painstaking separation of individual layers by dissection or by obtaining micrometer thin cross-sections. The latter usually requires the expertise of an individual trained in microtomy and even then, the very structure of the laminate could affect the outcome of the spectral results. The recent development of attenuated total internal reflection (ATR) infrared microspectroscopy imaging has provided a new avenue for the analysis of these multilayer structures. This report compares ATR infrared microspectroscopy imaging with conventional transmission infrared microspectroscopy imaging. The results demonstrate that the ATR method offers improved spatial resolution, eliminates a variety of competing optical processes, and requires minimal sample preparation relative to transmission measurements. These advantages were illustrated using a polymer laminate consisting of 11 different layers whose thickness ranged in size from 4–20 μm. The spatial resolution achieved by using an ATR-FTIR (Fourier transform infrared spectroscopy) imaging technique was diffraction limited. Contrast in the ATR images was enhanced by principal component analysis.

Many viruses, with distinct replication strategies, activate DNA-damage response pathways, including the lentivirus human immunodeficiency virus (HIV) and the DNA viruses Epstein–Barr virus (EBV), herpes simplex virus 1, adenovirus and SV40. DNA-damage response pathways involving DNA-dependent protein kinase, ataxia-telengiectasia mutated (ATM) and ‘ataxia-telengiectasia and Rad3-related’ (ATR) have all been implicated. This review focuses on the effects of HIV and EBV replication on DNA repair pathways. It has been suggested that activation of cellular DNA repair and recombination enzymes is beneficial for viral replication, as illustrated by the ability of suppressors of the ATM and ATR family to inhibit HIV replication. However, activation of DNA-damage response pathways can also promote apoptosis. Viruses can tailor the cellular response by suppressing downstream signalling from DNA-damage sensors, as exemplified by EBV. New small-molecule inhibitors of the DNA-damage response pathways could therefore be of value to treat viral infections.

Breast cancer is one of the most common causes of cancer-related mortality in women. It affects more than one in nine women over their lifetime. Although most breast cancers are sporadic, the genetics and molecular biology of the heritable forms of breast cancer have provided valuable insights into not only breast cancer but also cancers in general. Among the mutations linked to heritable breast cancers, the mutations in the breast cancer 1 (BRCA1) gene are the best characterised. The BRCA1 gene encodes a nuclear protein that is important for maintaining genome integrity. However, a growing list of BRCA1-associated proteins suggests that BRCA1 has diverse and unexpected functions.