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A multimodal imaging platform can ascertain the spatial resolution and intracellular uptake of both the nanocarrier and drug as unique species.

A fundamental question crucial to surface-enhanced spatially offset Raman spectroscopy (SESORS) imaging and implementing it in a clinical setting for in vivo diagnostic purposes is whether a SESORS image can be used to determine the exact location of an object within tissue? To address this question, multiple experimental factors pertaining to the optical setup in imaging experiments using an in-house-built point-collection-based spatially offset Raman spectroscopy (SORS) system were investigated to determine those critical to the three-dimensional (3D) positioning capability of SESORS. Here, we report the effects of the spatial offset magnitude and geometry on locating nanoparticles (NPs) mixed with silica powder as an imaging target through tissue and outline experimental techniques to allow for the correct interpretation of SESORS images to ascertain the correct location of NPs in the two-dimensional x, y-imaging plane at depth. More specifically, the effect of "linear offset-induced image drag" is presented, which refers to a spatial distortion in SESORS images caused by the magnitude and direction of the linear offset and highlight the need for an annular SORS collection geometry during imaging to neutralize these asymmetric effects. Additionally, building on these principles, the concept of "ratiometric SESORS imaging" is introduced for the location of buried inclusions in three dimensions. Together these principles are vital in developing a methodology for the location of surface-enhanced Raman scattering-active inclusions in three dimensions. This approach utilizes the relationship between the magnitude of the spatial offset, the probed depth, and ratiometric analysis of the NP and tissue Raman intensities to ultimately image and spatially discriminate between two distinct NP flavors buried at different depths within a 3D model for the first time. This research demonstrates how to accurately identify multiple objects at depth in tissue and their location using SESORS which addresses a key capability in moving SESORS closer to use in biomedical applications.

The host-guest chemistry of coordination cages continues to promote significant interest, not least because confinement effects can be exploited for a range of applications, such as drug delivery, sensing, and catalysis. Often a fundamental analysis of noncovalent encapsulation is required to provide the necessary insight into the design of better functional systems. In this paper, we demonstrate the use of various techniques to probe the host-guest chemistry of a novel Pd2L4 cage, which we show is preorganized to selectively bind dicyanoarene guests with high affinity through hydrogen-bonding and other weak interactions. In addition, we exemplify the use of Raman spectroscopy as a tool for analyzing coordination cages, exploiting alkyne and nitrile reporter functional groups that are contained within the host and guest, respectively.

River water quality is strongly affected by droughts and heatwaves worldwide. However, these effects have only been studied in a small number of river basins and regions, mainly in the US, Europe, or Australia. In this study, we analyse the large-scale responses in river water quality under droughts, heatwaves and compound events for 300,000+ water quality monitoring stations worldwide between 1980-2021. We include 16 water quality constituents in the analysis, grouped into general constituents (e.g. water temperature, salinity, dissolved oxygen), biological constituents (e.g. faecal coliform, biochemical oxygen demand) and emerging contaminants (e.g. pesticides and pharmaceuticals). Further, we assess the water quality responses to droughts and heatwaves in relation to climate, land use and level of wastewater treatment. We find a general deterioration in river water quality under droughts and heatwaves globally for most types of water quality constituents, with on average higher water temperatures (+27%), increases in salinity (+23%) and lower concentrations of dissolved oxygen (-17%). We also find that climate type, land use and level of wastewater treatment have a significant effect on the magnitude of water quality responses under droughts and heatwaves. The median increase in river temperature under compound drought-heatwaves strongly depends on climate, with for example higher increases in the Polar climate zone (+4.5°C) compared to the Tropical zone (+2.1°C). Increases in salinity under droughts are on average twice as large in irrigated regions compared to non-irrigated regions. Phosphorus and nitrogen concentrations in rivers can either increase or decrease during drought events, depending on the type of nutrient form (dissolved versus particulate) and land use (urban versus rural). Higher levels of wastewater treatment lead to a stronger reduction in faecal coliform (an indicator of pathogens) during droughts and heatwaves. Compared to previous local and regional-scale analyses, this study provides a more consistent and broader understanding of how droughts and heatwaves affect river water quality. In addition, the results from this study could be used to validate large-scale models of river water quality under droughts and heatwaves.

This article investigated the paradox between church response to apartheid and resulting action at the local level in the South African churches of European origin from the perspective of the Presbyterian Church of South(ern) Africa (PCSA). It indicated that this discrepancy arose between the reflections (cerebral faith) at the highest levels of church councils, which operated in an intermittent manner and at a distance, compared with the responses (praxis as faith in action) of local church members who lived at the coalface of the struggle and sought to witness in a society dominated by racism, where the tension between faith and politics was most evident. The primary focus was on two inter-racial congregations, one of the PCSA, the other a united congregation in which the PCSA participated. This study used primary and secondary sources. The theoretical framework of the article was Thomas Groome’s approach of shared praxis. Contribution: This article contributed to the history of the apartheid era in ecclesiastical contexts. It demonstrated the anomalies that arose within different constituencies within churches of European origin by investigating the situation in one particular denomination. This was a discussion of the relationship of faith and politics in the private and public domains, which takes account of developments within a shared praxis approach.&nbsp

The rapid detection of biomolecules in a point of care (POC) setting is very important for diagnostic purposes. A platform which can provide this, whilst still being low cost and simple to use, is paper-based lateral flow immunoassays (LFIA). LFIA combine immunology and chromatography to detect a target by forming an immunocomplex with a label which traps them in a test zone. Qualitative analysis can be performed using the naked eye whilst quantitative analysis takes place by measuring the optical signal provided by the label at the test zone. There are numerous detection methods available; however, many suffer from low sensitivity and lack of multiplexing capabilities or are poor at providing POC quantitative analysis. An attractive method to overcome this is to use nanoparticles coated in Raman reporters as the labelled species and to analyse test zones using surface-enhanced Raman scattering (SERS). Due to the wide variety of metal nanoparticles, Raman reporter and laser excitations that are available, SERS-based LFIA have been adapted to identify and quantify multiple targets at once. Large Raman microscopes combined with long mapping times have limited the platform to the lab; however, by transferring the analysis to portable Raman instruments, rapid and quantitative measurements can be taken at the POC without any loss in sensitivity. Portable or handheld SERS-LFIA platforms can therefore be used anywhere, from modern clinics to remote and resource-poor settings. This review will present an overview of SERS-based LFIA platforms and the major recent advancements in multiplexing and portable and handheld detection with an outlook on the future of the platform. Graphical abstract

Vibrational spectroscopic chemical imaging is an important tool in the pharmaceutical industry for characterising the spatial distribution of components within final drug products. The applicability of these techniques is currently limited by the long data acquisition times required to obtain high-definition chemical images of a sample surface. Advancements in quantum cascade laser (QCL) technology have provided an exciting new opportunity for infrared (IR) imaging. Instead of collecting a full IR spectrum at each point, it is possible to focus on distinct spectral bands to reduce imaging data collection time. This study explores a laser direct infrared (LDIR) chemical imaging approach that couples QCL technology with rapid scanning optics to provide high-definition chemical images at an order of magnitude faster than traditional imaging techniques. The capabilities of LDIR chemical imaging were evaluated for pharmaceutical formulations and compared with other established spectroscopic chemical imaging techniques including Raman, near-infrared (NIR) and scanning electron microscopy-energy dispersive X-ray (SEM-EDX) spectroscopy with regards to data acquisition time and image quality. The study showed that LDIR imaging provided high-definition component distribution maps comparable to Raman and SEM-EDX at orders of magnitude faster in terms of time. The ability to obtain high-definition chemical images of the whole tablet surface in relatively fast time frames indicates LDIR imaging could be a promising tool in the pharmaceutical industry to rapidly characterise the size and distribution of components within tablets and could help enhance drug product manufacturing understanding.

Quantitative drug imaging in live cells is a major challenge in drug discovery and development. Many drug screening techniques are performed in solution, and therefore do not consider the impact of the complex cellular environment in their result. As such, important features of drug-cell interactions may be overlooked. In this study, Raman microscopy is used as a powerful technique for semi-quantitative imaging of Strathclyde-minor groove binders (S-MGBs) in mammalian cells under biocompatible imaging conditions. Raman imaging determined the influence of the tail group of two novel minor groove binders (S-MGB-528 and S-MGB-529) in mammalian cell models. These novel S-MGBs contained alkyne moieties which enabled analysis in the cell-silent region of the Raman spectrum. The intracellular uptake concentration, distribution and mechanism were evaluated as a function of the p

Statins have displayed significant, although heterogeneous, anti-tumour activity in breast cancer disease progression and recurrence. They offer promise as a class of drugs, normally used for cardiovascular disease control, that could have a significant impact on the treatment of cancer. Understanding their mode of action and accurately assessing their efficacy on live cancer cells is an important and significant challenge. Stimulated Raman scattering (SRS) microscopy is a powerful, label-free imaging technique that can rapidly characterise the biochemical responses of live cell populations following drug treatment. Here, we demonstrate multi-wavelength SRS imaging together with spectral phasor analysis to characterise a panel of breast cancer cell lines (MCF-7, SK-BR-3 and MDA-MB-231 cells) treated with two clinically relevant statins, atorvastatin and rosuvastatin. Label-free SRS imaging within the high wavenumber region of the Raman spectrum (2800-3050 cm -1) revealed the lipid droplet distribution throughout populations of live breast cancer cells using biocompatible imaging conditions. A spectral phasor analysis of the hyperspectral dataset enables rapid differentiation of discrete cellular compartments based on their intrinsic SRS characteristics. Applying the spectral phasor method to studying statin treated cells identified a lipid accumulating phenotype in cell populations which displayed the lowest sensitivity to statin treatment, whilst a weaker lipid accumulating phenotype was associated with a potent reduction in cell viability. This study provides an insight into potential resistance mechanisms of specific cancer cells towards treatment with statins. Label-free SRS imaging provides a novel and innovative technique for phenotypic assessment of drug-induced effects across different cellular populations and enables effective analysis of drug-cell interactions at the subcellular scale.

Lachenalia komsbergensis G.D.Duncan, sp. nov. (Figs. 1, 2) Type:— SOUTH AFRICA. Northern Cape: Komsberg Pass, 2.1 km north of entrance to farm De Plaat on R354 from Matjiesfontein to Sutherland (3220 DC), solitary plants and scattered clumps on flats among low scrub, in deep, beige alluvium above dry riverbed, in full sun, elev. 1144 m, 8 October 2001, Duncan 459 (holotype NBG). This new species differs from L. juncifolia Baker (1871: 409) in its leaves that are deeply canaliculate for their entire length, its spreading, white perianth with narrowly spreading stamens, its slightly larger globose seeds (1.2–1.3 × 1.3–1.4 mm) with a matt black testa and rugose primary sculpturing, a longer strophiole 0.5–0.6 mm long, and in its taller stature up to 300 mm high in full flower. Deciduous, winter-green geophyte 150–300 mm high. Bulb subglobose, 15–20 mm in diam., offset-forming (1 or 2 offsets formed per bulb, but not necessarily every year); tunic multi-layered, outer tunics spongy, dark brown, inner tunics membranous, light brown; cataphyll translucent white, adhering to leaf bases, apex obtuse. Leaves 2, linear, 200–260 × 1–15 mm, suberect or recurved, deeply canaliculate, upper surface light green, lower surface light green in upper two thirds, heavily magenta- or purple-barred in lower third; apex acute; primary seedling leaf terete, erect. Inflorescence racemose, 10–48-flowered, flower head 40–120 mm long; peduncle erect to suberect, 100–155 mm long, rigid, light green, heavily speckled with dull purple; rachis light green and heavily purple-speckled in lower two thirds, white in upper third; lower bracts ovate, 1–4 × 2–3 mm, upper bracts lanceolate, 1–2 × 1 mm, white; pedicels suberect, 5–10 mm long, white. Perianth zygomorphic, oblong-campanulate, suberect; tube cup-shaped, 3 mm long, white; outer tepals ovate, 4–5 × 3–4 mm, apices flat, apical gibbosity deep pink; inner tepals obovate, 5–7 × 3–5 mm, translucent white, median keel light green in upper half, apices recurved. Stamens well exserted, narrowly spreading; filaments 8–10 mm long, white; anthers 0.8–1.0 mm long, pollen yellow. Ovary obovoid, 3 × 2 mm, light green; style well exserted, straight, 9–10 mm long, white; stigma minutely capitate. Capsule obovoid, 6–7 × 4–5 mm. Seed globose, 1.2–1.3 × 1.3–1.4 mm, matt, black; primary sculpturing rugose; strophiole 0.5–0.6 mm long, ridged. Flowering time: September to October. Etymology:— The specific epithet komsbergensis commemorates the Komsberg in the southern Great Karoo, to which this species is endemic. Other material examined:— SOUTH AFRICA. Northern Cape: Komsberg Pass, 2.1 km north of entrance to farm De Plaat on R354 from Matjiesfontein to Sutherland (3220 DC), solitary plants and scattered clumps on flats among low scrub, in deep, beige alluvium above riverbed, in full sun, elev. 1144 m, 1 September 2000, Summerfield s.n. (NBG); Komsberg Pass, farm Damslaagte (3220 DC), at river crossing, 19 October 2008, Saunders & Manning 3196 (NBG). Notes:— The first collection of flowering specimens was made at the type location by G.C. Summerfield in September 2000. A subsequent record of flowering plants was made at the same location by G.D. Duncan on 8 October 2001, when the type specimens were collected and habitat photographs were taken. Material from this collection has since flowered every year in cultivation in the bulb nursery at Kirstenbosch. A third collection at late flowering stage was made close to the type location by R. Saunders and J. Manning on 19 October 2008. Diagnostic features and affinities:— Lachenalia komsbergensis is recognised in flower by an erect or suberect, rigid, light green peduncle that is heavily speckled with dull purple, bearing a raceme of small oblong-campanulate, spreading, white and pink flowers carried on white, suberect pedicels (Fig. 1 A). It has shallowly cup-shaped perianth tubes and narrowly spreading tepals. The outer tepals have a prominent deep pink median keel and apical gibbosity, and the strongly protruding inner tepals have a dull pink median keel. The flowers have bracts that are ovate at the base of the inflorescence and lanceolate above, and well exserted, narrowly spreading, white stamens. The inflorescence emerges towards the end of the growing season, as the leaves start to wither. The species is further recognised by two linear, suberect or recurved, deeply canaliculate, conduplicate leaves, with acute apices. The upper and lower surfaces are light green, and the lower surfaces are heavily magenta- or purple-barred in the lower third, and green-barred in the upper two thirds. The primary seedling leaf is terete, with erect orientation. The fruit is an obovoid capsule containing globose, matt black seeds with rugose primary sculpturing, and ridged strophioles. Lachenalia komsbergensis is included within subsect. Lachenalia of sect. Lachenalia (Duncan et al. 2022). It was initially considered to be a tall-growing form of L. juncifolia, but in phylogenetic analysis it was retrieved as sister to two accessions of L. longibracteata Phillips (1931: 405), in a phylogenetically strongly isolated position from L. juncifolia, the latter falling within sect. Linearifoliae (Duncan et al. 2022). L. komsbergensis differs from L. juncifolia in having leaves that are deeply canaliculate for their entire length (versus slightly canaliculate in the lower two thirds and terete in the upper third), a spreading, mostly white perianth (versus cernuous and cream-coloured, pink, magenta or purple), narrowly spreading stamens (versus straight), a taller stature up to 300 mm high (versus up to 200 mm high), slightly larger seeds (1.2–1.3 × 1.3–1.4 mm) with a matt black testa and rugose primary sculpturing (versus 1.1– 1.2 × 1.3 mm, with a glossy black testa and smooth primary sculpturing), and a substantially longer strophiole 0.5–0.6 mm long (versus 0.2 mm long). Furthermore, L. juncifolia has a much longer flowering period (August to December) and a much wider distribution from Calvinia in the western Great Karoo to Herbertsdale in the southern Cape (Duncan 2012). Distribution and habitat:— Lachenalia komsbergensis occurs in the Succulent Karoo biome in the southern part of the Northern Cape, and is endemic to the Komsberg, a component of the Hantam-Roggeveld Centre of Plant Endemism (Van Wyk & Smith 2001, Mucina & Rutherford 2006, Clark et al. 2011). It is highly localised to open flats adjacent to a seasonal river in the southern Komsberg, at an elevation of 1144 m (Fig. 2). The area receives most of its rainfall in winter but is transitionary between winter and summer rainfall regimes (Clark et al. 2011). The plants occur as scattered solitary individuals or in small groups of up to four plants on flats in deep, beige alluvium. The bulbs are shallowly seated and occur among low, sparse, scrubby vegetation including perennials of the family Asteraceae, in Central Mountain Shale Renosterveld, a vegetation type which occupies a borderline position straddling the Fynbos, Succulent Karoo and marginally the Nama Karoo biomes (Mucina & Rutherford 2006) (Fig. 1 B, C). The species flowers late in the spring season (late September to October), at a time when the leaves are already beginning to desiccate., Published as part of Duncan, Graham D., 2023, Four new species and three taxonomic adjustments in Lachenalia (Asparagaceae: Scilloideae) from southern and western South Africa, pp. 261-273 in Phytotaxa 585 (4) on pages 262-265, DOI: 10.11646/phytotaxa.585.4.2, http://zenodo.org/record/7703809, {"references":["Baker, J. G. (1871) A revision of the genera and species of herbaceous capsular gamophyllous Liliaceae. 17. Lachenalia. Journal of the Linnean Society of Botany 11: 349 - 410. https: // doi. org / 10.1111 / j. 1095 - 8339.1870. tb 00068. x","Duncan, G. D., Schlichting, C. D., Forest, F., Ellis, A. G., Lemmon, A. R., Lemmon, E. M. & Verboom, G. A. (2022) A new sectional classification of Lachenalia (Asparagaceae) based on a multilocus DNA phylogeny. Taxon 71: 563 - 586. https: // doi. org / 10.1002 / tax. 12683","Phillips, E. P. (1931) Lachenalia longibracteata. The Flowering Plants of South Africa 11: t. 405.","Duncan, G. D. (2012) The genus Lachenalia. Botanical magazine monograph. Royal Botanic Gardens, Kew, 479 pp.","Van Wyk, A. E. & Smith, G. F. (2001) Regions of floristic endemism in southern Africa. Umdaus Press, Hatfield, 199 pp.","Mucina, L. & Rutherford, M. C. (2006) The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria, 807 pp.","Clark, V. R., Barker, N. P. & Mucina, L. (2011) The Roggeveldberge - notes on a botanically hot area on a cold corner of the Southern Great Escarpment, South Africa. South African Journal of Botany 77: 112 - 126. https: // doi. org / 10.1016 / j. sajb. 2010.07.001"]}

A novel phylogenetic hypothesis for Lachenalia (Asparagaceae; Scilloideae; Hyacintheae) based on multilocus DNA sequence data has revealed the existence of four morphologically, ecologically and/or geographically distinct species, and supports the elevation of three existing subspecies to the species level. The new species and combinations are presented here. The new species are Lachenalia komsbergensis from the Komsberg in the southern Great Karoo (Northern Cape), Lachenalia inflata from the Hantam-Roggeveld escarpment in the western Great Karoo (Northern Cape), Lachenalia granitica from the Cape West Coast (Western Cape) and Lachenalia filamentosa from the Cape West Coast, Breede River Valley and Overberg (Western Cape). The taxa elevated from subspecies to species level are Lachenalia rogersii (previously L. mediana subsp. rogersii) from the Breede River Valley (Western Cape), Lachenalia glaucina (previously L. orchioides subsp. glaucina) from the southern Cape Peninsula (Western Cape) and Lachenalia parviflora (previously L. orchioides subsp. parviflora) from the northeastern Cape Peninsula (Western Cape).

Lachenalia granitica G.D.Duncan, sp. nov. (Figs. 1, 2) Type: — SOUTH AFRICA. Western Cape: Vredenburg (3217 DD), among granite rocks immediately south of town, elev. 167 m, 6 August, 1962, Barker 9680 (holotype NBG!). This new species differs from L. longibracteata in having a spicate inflorescence with longer, metallic blue and often blue-spotted outer tepals (9–10 mm long), translucent white inner tepals, longer filaments (9–11 mm long), a shorter style (9–10 mm long), leaf upper surfaces that are often shallowly pustulate, a smaller globose seed (0.9–1.0 × 1.0 mm) with a shorter inflated strophiole (0.8 mm long), and a flowering period that begins much earlier in midwinter (late June). Deciduous, winter-green geophyte 90–330 mm high. Bulb globose, 10–25 mm in diam., solitary; tunic multilayered, outer tunics spongy, dark brown, inner tunics membranous; cataphyll 10–32 × 10–15 mm, translucent white, apex obtuse. Leaf 1 or 2, lanceolate, 35–190 × 8–28 mm, suberect, dull green, upper surface usually smooth, rarely covered with flattened pustules; margins coriaceous; leaf bases clasping, 20–40 mm long, light green; primary seedling leaf prostrate, flat. Inflorescence spicate, 7–50-flowered, dense, peduncle erect or suberect, glaucous, plain or lightly green-spotted; bracts ovate at base of inflorescence, becoming lanceolate above, 2–25 × 3–5 mm, translucent white. Perianth zygomorphic, oblong-campanulate, suberect, sweet-scented; tube cup-shaped, 4–5 mm long, metallic blue or blue-green, plain or darker blue-spotted; tepals light metallic blue, plain or darker blue-spotted; outer tepals narrowly ovate, 9–10 × 3–4 mm, apical gibbosity brown or greenish brown; inner tepals obovate, 10–11 × 4–5 mm, translucent white, fading to brownish maroon, apices obtuse, slightly recurved, median keels bright green. Stamens included or shortly exserted; filaments declinate, 9–11 mm long, white; anthers oblong, 1 mm long, pollen yellow. Ovary ellipsoid, 3 × 2 mm, dull green; style declinate, 9–10 mm long, white, becoming strongly exserted in fruit; stigma minutely capitate. Capsule ellipsoid, 8–10 × 5–6 mm. Seed globose, 0.9–1.0 × 1.0 mm, matt, black, secondary sculpturing rugose; strophiole inflated, 0.8 mm long, smooth, glossy black. Flowering time: June to September. Etymology:— The specific epithet granitica refers to the granite rocky outcrops and granitic flats of the Cape West Coast, to which this species is endemic. Other material examined:— SOUTH AFRICA. Western Cape: Witklip south of Vredenburg (3217 DD), 9 August 1984, Barker 10250 (NBG); granite outcrop south of Vredenburg, off R399 (3217 DD), among houses, in loamy clay soil, westerly aspect, 20 June 2006, elevation 167 m, Cowell & Nurrish 537 (NBG); Stompneus, northwest of St. Helena Bay (3217 DD), 27 June 1967, Hall 3139 (NBG); above Stompneus (3217 DD), 17 June 1965, Barker 10567 (NBG). Nooitgedacht Farm near St Helena Bay (3218 CC), 28 June 1972, Barker 10228 (NBG). Entrance to Saldanha off R399, on granite hill above town (3317 BB), occasional in loamy clay on west-facing rocky slope, 9 October 1983, Duncan 119 (NBG). Langebaan (3318 AA), 21 July 1938, Lewis s.n. sub. NBG 222/32 (NBG). Darling (3318 AD), 23 August 1947, Barker 4599 (NBG); Waylands Farm Flower Reserve east of Darling (3318 AD), 8 September 1974, Barker s.n. (NBG, photo.). Notes:— The earliest known collection of L. granitica is that of G.J. Lewis who recorded it in flower at Langebaan on the Cape West Coast on 21 July, 1938. Most collections have been made in the vicinity of Vredenburg to the north. The species is becoming increasingly threatened by coastal housing development. Diagnostic features and affinities:— Lachenalia granitica is recognised in flower by a dense spike of suberect, oblong-campanulate, sweet-scented flowers with metallic blue or blue-green perianth tubes, light metallic blue outer tepals which may be plain or darker blue-spotted, and protruding, translucent white inner tepals with obtuse, slightly recurved apices. The outer tepals have a prominent brown or greenish brown apical gibbosity, and the inner tepals have bright green median keels and fade to brownish maroon (Fig. 1 G, H, I). Each flower is subtended by a prominent lanceolate, translucent white bract, and in the upper part of the inflorescence the bracts may be up to 25 mm long (Fig. 1 G). The plant produces one or two lanceolate, dull green, suberect leaves with coriaceous margins, mostly with smooth surfaces, or rarely with sporadic flattened pustules. The ripe fruit is an ellipsoid capsule containing globose, matt, black seeds with an inflated, smooth, glossy strophiole. Lachenalia granitica is a member of sect. Lachenalia, subsect. Lachenalia (Duncan et al. 2022). Due to its prominent floral bracts, and similar oblong-campanulate flowers, it has previously been regarded as a blue-flowered form of L. longibracteata (Duncan 2012), however in phylogenetic analysis it was retrieved as sister to the turquoise, tubular-flowered L. viridiflora Barker (1972: 179) (with which it occurs sympatrically on granite outcrops in northern parts of its Cape West Coast range), within the uppermost clade of subsect. Lachenalia (Duncan et al. 2022). L. longibracteata differs from L. granitica in having a racemose inflorescence with shorter, greenish yellow outer tepals (6–9 mm long), shorter filaments (7–9 mm long), a longer style (11–14 mm long), leaf upper surfaces that are always smooth, a larger globose seed (1.1 × 0.9 mm) with a longer inflated strophiole (1.0 mm long) and a later flowering period from early to late spring (late August to mid-October). Distribution and habitat:— Lachenalia granitica occurs in the Fynbos Biome and is confined to the Cape West Coast, extending from Darling in the south to St. Helena Bay in the north (Fig. 2). It is endemic to granite outcrops and flats, occurring among low scrub in partially shaded aspects within boulder crevices in dark brown, loamy soils in Saldanha Granite Strandveld, and in open aspects on granite flats, in Swartland Granite Renosterveld (Mucina & Rutherford 2006). The plants occur as scattered solitary individuals or in small groups, and when in flower, are inconspicuous among surrounding vegetation. Flowering commences in mid-winter and ends in early spring (late June to early September). Near Vredenburg, the flowerheads are grazed by steenbuck (Raphicerus campestris) and in winter the bulbs are excavated and eaten by Cape porcupines (Hystrix africaeaustralis) (Duncan 2012)., Published as part of Duncan, Graham D., 2023, Four new species and three taxonomic adjustments in Lachenalia (Asparagaceae: Scilloideae) from southern and western South Africa, pp. 261-273 in Phytotaxa 585 (4) on pages 266-267, DOI: 10.11646/phytotaxa.585.4.2, http://zenodo.org/record/7703809, {"references":["Duncan, G. D., Schlichting, C. D., Forest, F., Ellis, A. G., Lemmon, A. R., Lemmon, E. M. & Verboom, G. A. (2022) A new sectional classification of Lachenalia (Asparagaceae) based on a multilocus DNA phylogeny. Taxon 71: 563 - 586. https: // doi. org / 10.1002 / tax. 12683","Duncan, G. D. (2012) The genus Lachenalia. Botanical magazine monograph. Royal Botanic Gardens, Kew, 479 pp.","Barker, W. F. (1972) A new species of Lachenalia from the south-western Cape. Journal of South African Botany 38: 179 - 183.","Mucina, L. & Rutherford, M. C. (2006) The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria, 807 pp."]}

Lachenalia inflata G.D.Duncan, sp. nov. (Figs. 1, 2) Type: — SOUTH AFRICA. Northern Cape: Akkerendam Nature Reserve, Calvinia (3119 BD), stony clay flats and lower slopes of Hantamsberg Mountains, among low scrub, elev. 1139 m, 22 July 1961, Barker 9319 (holotype NBG!). This new species differs from L. mutabilis Loddiges ex Schultes & Schultes in Linnaeus (1830: 1710) in having a bright yellow perianth with the upper two inner tepals equal in length to the lower inner tepal, and in its shorter filaments and oblong, narrower seeds with an inflated raphe. Deciduous, winter-green geophyte 80–220 mm high. Bulb subglobose, 15–22 mm in diam., solitary; tunic multilayered, outer tunics spongy, dark brown, inner tunics membranous, translucent light brown; cataphyll translucent white, apex obtuse. Leaf 1, rarely 2, lanceolate, 100–150 × 10–20 mm, suberect, conduplicate, leathery, upper and lower surfaces green or glaucous, sometimes heavily flushed with brownish purple, or heavily purple- or greenblotched along median; margins thickened/cartilaginous, slightly to strongly undulate, sometimes crisped; leaf bases clasping, 10–20 mm long, light green, sporadically or densely marked with purplish or green botches on outer surface; primary seedling leaf prostrate, flat. Inflorescence spicate, 10–35-flowered; peduncle erect or suberect, moderately or strongly inflated above, maroon, or dull mauve-flushed in upper half, light green and mauve-spotted in lower half; rachis inflated and mauve-flushed in lower half, shading to brownish green in upper half; sterile apex 10–20 mm long, light green or light mauve; lower bracts cup-shaped, 1 × 2 mm, translucent white, upper bracts lanceolate, 2–5 × 1 mm, translucent white. Perianth zygomorphic, urceolate, slightly cernuous; perianth tube cup-shaped, 2–3 mm long, light greenish yellow or bright yellow; outer tepals ovate, 6–7 × 4 mm, bright yellow or greenish yellow, apices straight, apical gibbosity dark yellow, brown or brownish green; inner tepals obovate, 7–9 × 3–4 mm, bright yellow or greenish yellow, apices slightly recurved, median keel dull brown or brownish green. Stamens declinate, included; filaments 5–6 mm long, white. Ovary ellipsoid, 4 × 2 mm, light green; style declinate, included, 5 mm long, white, stigma minutely capitate. Capsule ellipsoid, 8–9 × 4–5 mm. Seed oblong, 1.2 × 0.9 mm, glossy, smooth, black; strophiole 0.7 mm long, glossy, inflated, smooth; raphe inflated. Flowering time: July to September. Etymology:— The specific epithet inflata is descriptive of the inflated upper part of the peduncle. Other material examined:— SOUTH AFRICA. Northern Cape: 12 km west of Calvinia on R355 to Loeriesfontein (3119 BC), on red, sandy clay flats, among low scrub, 4 September 2007, Harrower 3594 (NBG, photo); Akkerendam Nature Reserve, Calvinia (3119 BD), stony clay flats below Hantam Mountains, among low scrub, 26 August 2007, Avenant s.n. (NBG, photo); Farm Hangnes, Leliekrantz Road NW of Middelpos (3120 CC), scattered solitary plants on flats among low scrub, in deep red sand, in full sun or light shade of bushes, elev. 1189 m, 24 September 2015, Duncan 666 (NBG). Notes:— The first collection of L. inflata was made by W.F. Barker within the Akkerendam Nature Reserve at the base of the Hantam Mountains at Calvinia on 22 July 1961. On 22 September 2006, G.C. Summerfield recorded it on the farm Hangnes northwest of Middelpos in the Roggeveld, and he was the first to note that the oblong seeds of this species differed markedly from the globose ones of L. mutabilis, and thus suspected it to represent an undescribed species. In August 2007, F. Avenant photographed it in flower at Akkerendam Nature Reserve, and in September 2007, A.D. Harrower recorded it in flower just west of Calvinia. During a visit to Hangnes on 24 September 2015, the plant was sampled and studied in habitat by G.D. Duncan. Diagnostic features and affinities:— Lachenalia inflata is recognised in flower by an erect or suberect spike of urceolate, bright yellow or greenish yellow, slightly cernuous flowers carried on a strongly inflated, maroon, or dull mauve-flushed peduncle which is marked with purple or maroon blotches (Fig. 1 D, E). It has shallowly cup-shaped perianth tubes, the outer tepals have a dark yellow, brown or greenish brown apical gibbosity, and the protruding inner tepals have a dark yellow, dull brown or brownish green median keel. The flowers have included, declinate stamens, and bracts that are cup-shaped at the base of the inflorescence and lanceolate above. The plant usually has a solitary leathery lanceolate leaf (rarely 2) which is conduplicate or deeply channelled, and the margins are thickened/ cartilaginous and slightly to strongly undulate or sometimes crisped. The ripe fruit is an ellipsoid capsule containing oblong, glossy black seeds with a smooth, black strophiole and an inflated raphe. Lachenalia inflata is included within subsect. Oncoraphae of sect. Lachenalia (Duncan et al. 2022). It was initially considered to be merely a yellow-flowered form of L. mutabilis, but in phylogenetic analysis it was retrieved as sister to the sister pair L. bulbifera (Cirillo 1788: 35) Engler (1899: 321) and L. punctata Jacquin (1789: 323), two widespread, long-tubed, tubular-flowered lachenalias mainly from coastal parts of the Western and Northern Cape. These three taxa constitute the only members of subsect. Oncoraphae and are united by the possession of seeds with an inflated raphe (Duncan et al. 2022). L. mutabilis differs from L. inflata in having a light blue perianth tube, greenishbrown, light to deep mauve outer tepals with prominent brown apical gibbosities, and inner tepals that are yellowishgreen or translucent white, with brown or green median keels, with the lower inner tepal slightly longer than the upper inner tepals. It differs further in having longer filaments 7–9 mm long (versus 5–6 mm long), globose seeds (versus oblong) with a longer length range of 1.2–1.4 mm (versus 1.2 mm) and are wider (1.3–1.4 mm, versus 0.9 mm), and have no inflated raphe. Distribution and habitat:— Lachenalia inflata occurs within the Succulent Karoo Biome and is currently known from only three locations (Fig. 2). It frequents dwarf shrubland in Hantam Karoo vegetation on stony red clay flats and lower slopes of the Hantamsberg within the Akkerendam Nature Reserve at Calvinia, as well as on clay flats to the west of this town, whereas to the northwest of Middelpos (southeast of Calvinia), it occurs in Roggeveld Karoo vegetation in deep red sand (Mucina & Rutherford 2006) (Fig. 1 F). Plants occur as scattered solitary individuals or in groups of two, in open aspects or within the protection of low karroid scrub, and flowering takes place from late winter to spring (late July to late September)., Published as part of Duncan, Graham D., 2023, Four new species and three taxonomic adjustments in Lachenalia (Asparagaceae: Scilloideae) from southern and western South Africa, pp. 261-273 in Phytotaxa 585 (4) on pages 265-266, DOI: 10.11646/phytotaxa.585.4.2, http://zenodo.org/record/7703809, {"references":["Linnaeus, C. (1830) Systema vegetabilium 7 (2). J. G. Cotta, Stuttgart, 1816 pp.","Duncan, G. D., Schlichting, C. D., Forest, F., Ellis, A. G., Lemmon, A. R., Lemmon, E. M. & Verboom, G. A. (2022) A new sectional classification of Lachenalia (Asparagaceae) based on a multilocus DNA phylogeny. Taxon 71: 563 - 586. https: // doi. org / 10.1002 / tax. 12683","Cirillo, D. M. L. (1788). Plantarum rariorum regni Neapolitani 1. Naples, 39 pp.","Engler, H. G. A. (1899) Lachenalia Jacq. Notizblatt des Koniglichen Botanischen Gartens und Museums zu Berlin 2: 321.","Jacquin, N. J. (1789) Collectanea 2. C. F. Wappler, Vienna, 374 pp.","Mucina, L. & Rutherford, M. C. (2006) The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria, 807 pp."]}

Lachenalia filamentosa G.D.Duncan, sp. nov. (Figs. 1, 2) Type: — SOUTH AFRICA. Western Cape: Die Poort, 5 miles [8 km] south of Bredasdorp (3420 CA), in [limestone] sand, elev. 84 m, 3 September 1943, Barker 2500 (holotype NBG!). This new species differs from L. contaminata Aiton (1789: 460) in having well-exserted stamens (8–11 mm long), longer outer tepals (6–7 mm long), longer inner tepals (7–8 mm long) and a larger globose seed (1.1–1.2 × 1.0 mm). Deciduous, winter-green geophyte 110–150 mm high. Bulb subglobose, 15–20 mm in diam., offset-forming (1–3 offsets formed per bulb, but not necessarily every year); tunic multi-layered, outer tunics spongy, dark brown, inner tunics membranous, light brown; cataphyll translucent white, not adhering to leaf bases, apex obtuse. Leaves 3–6, linear, 120–155 × 1.5–5.0 mm, fleshy, glaucous-green, upper surface shallowly channelled in lower half, terete in upper half, lower surface glaucous-green or maroon-flushed, apices acute; primary seedling leaf erect, terete. Inflorescence racemose, 8–30-flowered; peduncle erect or suberect, light green, plain or purple-blotched in lower third, shading to dull maroon above; pedicels 2–3 mm long, suberect in flower, white or light magenta, becoming erect in fruit; bracts cup-shaped, green at base of inflorescence, shading to white above, 1–3 × 1–4 mm; perianth narrowly campanulate, suberect, spice-scented. Perianth tube cup-shaped, 2 mm long, white; outer tepals narrowly ovate, 6–7 × 3–4 mm, white, apical gibbosity narrow or prominent, magenta, median keel narrow or broad, magenta; inner tepals narrowly obovate, 7–8 × 3–4 mm, protruding 1 mm beyond outer tepals, white, median keel narrow or broad, magenta. Stamens well exserted, narrowly spreading; filaments white, inserted at distinctly different levels; filaments at base of outer tepals 8–9 mm long, filaments at base of inner tepals 10–11 mm long; anthers oblong, 1 mm long, maroon prior to anthesis, pollen yellow. Ovary ellipsoid, 2.0 × 1.8 mm, dull green, style straight, 10–11 mm long, becoming well exserted 7–8 mm beyond tepals as ovary enlarges, stigma capitate. Capsule ellipsoid, 7–8 × 4–5 mm, suberect. Seeds globose, 1.1 × 1.0 mm, glossy, black; strophiole rudimentary, 0.2 mm long, ridged. Flowering time: August to September. Etymology:— The specific epithet filamentosa refers to the thread-like, well-exserted filaments. Other material examined:— SOUTH AFRICA. Western Cape: southeast of Ludrift Farm, near Lambert’s Bay, wetland adjacent to sandveld fynbos (3218 AB), 27 September 2002, Low 7682 (NBG). Farm ‘ Uitkyk’, 10 km N of Porterville, on clay-shale (3218 DD), 24 September 2002, Helme 2754 (NBG). Citrusdal, 3 miles (5 km) north of town, 31 August 1938 (3219 CA), Salter 7492 (NBG). Eensaamheid Nature Reserve, 10 km west of Paarl, in waterlogged shale (3318 DD), 26 September 2002, Helme 2755, (NBG). Tulbagh, Voëlvlei Tortoise Reserve, in red-brown stony clay (3319 AC), 5 October 1989, Solomon 100 (NBG); Rawsonville, between old and new N1, on sandstone (3319 CB), 27 August 2007, Helme 4937 (NBG). Farm Boesmansrivier at foot of Riviersonderend Mountains, in white Table Mountain Sandstone, in fruit (3419 BB), 10 October 1979, Malan 117 (NBG); between Heuningrug and Wiesduif, on limestone koppie (3419 DB), 29August 1995, Paterson-Jones 573 (NBG). De Hoop Nature Reserve, behind Manager’s house, in limestone fynbos (3420 AD), 4 December, 2007, Duncan, Pekeur & Bennett 3596 (NBG); De Hoop Nature Reserve, in light brown loam (3420 AD), 21 August 1984, Scott 450 (NBG); De Hoop Nature Reserve, Melkkamer, in sand (3420 AD), 20 September 1984, van Wyk 1963 (NBG); Bredasorp (3420 CA), 4 September 1929, Barnes s.n. (BOL); Die Poort (3420 CA), 3 August 1940, Compton 9006 (NBG); Die Poort, 5 miles [8 km] south of Bredasdorp, on limestone (3420 CA), 19 September 1962, Nordenstam 1504 (NBG). Notes:— The earliest collections of L. filamentosa were made by P. Barnes near Bredasdorp on 4 September, 1929 (BOL), and T.M. Salter north of Citrusdal on 31 August, 1938 (NBG). The species has been recorded numerous times in the vicinity of Bredasdorp and the adjacent De Hoop Nature Reserve. Diagnostic features and affinities:— Lachenalia filamentosa is recognised in flower by dense racemes of narrowly campanulate, suberect white flowers, the outer tepals with a narrow or prominent, magenta apical gibbosity, and the outer and protruding inner tepals with a narrow or broad, magenta median keel. The stamens are well-exserted and narrowly spreading, with prominent maroon unripe anthers, and yellow ripe pollen (Fig. 1 J–L). During the fruiting stage, the pedicels change orientation from suberect to erect (Fig. 1 L). The 3–6 linear leaves have acute apices and are terete in the upper half, and shallowly channelled and considerably wider (up to 5 mm wide) in the lower half. Lachenalia filamentosa is a member of sect. Lachenalia, subsect. Angustae (Duncan et al. 2022). It was previously considered to be merely a form of L. contaminata with well-exserted stamens (Duncan 2012), however in phylogenetic analysis it was retrieved as sister to a typical form of L. contaminata, despite the fact that a different accession of a typical form of L. contaminata was retrieved in a phylogenetically isolated part of the ‘subsect. Angustae ’ clade (Duncan et al. 2022). L. contaminata differs from L. filamentosa in having included stamens (5 mm long), shorter outer tepals (5 mm long), shorter inner tepals (6–7 mm long) and a smaller globose seed (0.9–1.0 × 0.8–0.9 mm). Distribution and habitat:— Lachenalia filamentosa is fairly widely distributed in the western, southwestern and southern parts of the Western Cape, from De Hoop Nature Reserve in the south to Lambert’s Bay in the north (Fig. 2). It traverses a range of habitats and vegetation types, including limestone flats and hills in De Hoop Limestone Fynbos (Mucina & Rutherford 2006) (Fig. 1 L), sandstone mountain slopes in North Sonderend Sandstone Fynbos near Riviersonderend, and clay-shale flats and hills in Breede Shale Renosterveld near Tulbagh, and usually occurs in large colonies. Elevation ranges from 15 m on the south coast to 900 m in the northern foothills of the Riviersonderend Mountains. Flowering takes place from early to late spring (early August to late September)., Published as part of Duncan, Graham D., 2023, Four new species and three taxonomic adjustments in Lachenalia (Asparagaceae: Scilloideae) from southern and western South Africa, pp. 261-273 in Phytotaxa 585 (4) on pages 267-268, DOI: 10.11646/phytotaxa.585.4.2, http://zenodo.org/record/7703809, {"references":["Aiton, W. (1789) Hortus Kewensis 1. Nicol, London, 496 pp.","Duncan, G. D., Schlichting, C. D., Forest, F., Ellis, A. G., Lemmon, A. R., Lemmon, E. M. & Verboom, G. A. (2022) A new sectional classification of Lachenalia (Asparagaceae) based on a multilocus DNA phylogeny. Taxon 71: 563 - 586. https: // doi. org / 10.1002 / tax. 12683","Duncan, G. D. (2012) The genus Lachenalia. Botanical magazine monograph. Royal Botanic Gardens, Kew, 479 pp.","Mucina, L. & Rutherford, M. C. (2006) The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria, 807 pp."]}

The use of Raman spectroscopy to determine the radiation response of human glioma cells and how this response differs depending on the cell's position in the cell cycle.

Peptide fibre formation via molecular self-assembly is a key step in a range of cellular processes and increasingly considered as an approach to produce supramolecular biomaterials. We previously demonstrated the self-assembly of the tripeptide lysine-dityrosine (KYY) as a substrate for the formation of proton-conducting melanin-like materials. Point based Raman scattering is one of several techniques which were used to characterise the secondary structure of the KYY nanofibre but as is often the case with this type of fibre, the spectra are rather complex and in addition there were variations in intensity between samples making interpretation difficult. Using Raman mapping we show that, as a drop of KYY in solution dries, it self-assembles into two different fibre forms and the simpler spectra obtained for each are easier to interpret. The tyrosine amide marker bands, 852 and 828 cm −1, are present in both forms with similar intensities indicating the formation of a similar secondary structure in both forms with some stacking of the tyrosine rings. However, the tyrosine marker bands at 1614 and 1661 cm −1 vary considerably in intensity between the two forms. It is concluded that both forms consist of stacked polypeptide units joined by hydrogen bonds to form structures similar to β-sheet structures in longer peptides. There are other clear differences such the large intensity difference in the lysine side chain band at 1330 cm −1 and the relative intensities of the bands at 982 and 1034 cm −1. These differences are attributed to changes in the conformation of tyrosine side chains causing different electron withdrawing effects on the ring.

Antibiotic resistant bacteria constitute a global health threat. It is essential for healthcare professionals to prescribe the correct dose of an effective antibiotic to mitigate the bacterial infection in a timely manner to improve the therapeutic outcomes to the patient and prevent the dissemination of antibiotic resistance. To achieve this, there is a need to implement a rapid and ultra-sensitive clinical diagnosis to identify resistant bacterial strains and monitor the effect of antibiotics. In this review, we highlight the use of surface enhanced Raman scattering (SERS) as a powerful diagnostic technique for bacterial detection and evaluation. Initially, this is viewed through a lens covering why SERS can surpass other traditional techniques for bacterial diagnosis. This is followed by different SERS substrates design, detection strategies that have been used for various bacterial biomarkers, how SERS can be combined with other diagnostic platforms to improve its performance towards the bacterial detection and the application of SERS for antibiotic resistance diagnosis. Finally, the recent progress in SERS detection methods in the last decade for the "

Antibiotic resistant bacteria constitute a global health threat. It is essential for healthcare professionals to prescribe the correct dose of an effective antibiotic to mitigate the bacterial infection in a timely manner to improve the therapeutic outcomes to the patient and prevent the dissemination of antibiotic resistance. To achieve this, there is a need to implement a rapid and ultra-sensitive clinical diagnosis to identify resistant bacterial strains and monitor the effect of antibiotics. In this review, we highlight the use of surface enhanced Raman scattering (SERS) as a powerful diagnostic technique for bacterial detection and evaluation. Initially, this is viewed through a lens covering why SERS can surpass other traditional techniques for bacterial diagnosis. This is followed by different SERS substrates design, detection strategies that have been used for various bacterial biomarkers, how SERS can be combined with other diagnostic platforms to improve its performance towards the bacterial detection and the application of SERS for antibiotic resistance diagnosis. Finally, the recent progress in SERS detection methods in the last decade for the "Big 5" antibiotic resistant challenges as demonstrators of public health major threats is reviewed, namely: Methicillin-resistant Staphylococcus aureus (MRSA), Carbapenem-resistant Enterobacteriaceae (CRE) / Extended-spectrum beta-lactamases (ESBLs), Mycobacterium tuberculosis (TB), Vancomycin-resistant Enterococcus (VRE) and Neisseria Gonorrhoea (NG). This review provides a comprehensive view of the current state of the art with regard to using SERS for assessing antibiotic resistance with a future outlook on where the field go head in the coming years.