Longitudinal Bands Research Articles

Control of growth solution on the dimensions of gold nanorods accounted for LSPR sensitivity toward liquid ammonia sensing

In the present study, the effect of dimensions of gold nanorods on its sensing property to detect liquid ammonia was reported. Gold nanorods with two different aspect ratios (GNR1 and GNR2) derived from different lengths and diameters were synthesized using seed-mediated growth method, and the aspect ratio was controlled by changing the silver ion concentration in growth solution. The morphological and size measurement was performed using Transmission Electron Microscopy (TEM), and the average value of aspect ratio (AR) was found to be 3.0 and 3.2 for GNR1 and GNR2, respectively. The characteristics transverse and longitudinal mode of localized surface plasmon resonance (LSPR) have been clearly depicted in UV–vis absorption spectrum of both GNR1 and GNR2. The red shift in longitudinal mode of LSPR from 718 to 732 nm has been observed for GNR with change in aspect ratio from 3.0 to 3.2, respectively. These samples of GNR were tested for liquid ammonia sensing with concentration ranging from 100 to 500 ppm. A clear cut blue shift in longitudinal mode of LSPR of prepared gold nanorod was observed. However, the GNR2 was found to be more sensitive toward liquid ammonia sensing. The origin of such blue shifting and sensitivity of longitudinal mode of LSPR of gold nanorod was explained on the basis of orientation dependence and Dipolar Exciton Coupling Model of coupled plasmon in assemblies of anisotropic plasmonic nanoparticles. With the help of this model, blue shifting in longitudinal plasmon band was correlated with the enhanced formation of H-aggregation induced by dipolar coupling of GNR clusters followed by hydrogen bonding after successive addition of ammonia solution.

Nail disorders in skin of color: Approach to onychoscopic diagnosis

Onychoscopy provides a better understanding of nail lesions in terms of diagnosis, monitoring of progression and response to treatment. Author have put forward a simplified way to approach to a nail lesion by onychoscopy. Onychoscopy of pigmentary, inflammatory, infections, neoplastic and connective tissue diseases affecting the individual of skin of color are described to construct a basic outline for onychoscopic approach to a nail lesion. Onychoscopy shows homogenous dark band in longitudinal melanocytic nevus (LMN), irregular black pigment with irregular longitudinal lines in melanoma, multi-colored pigmented patches in fungal melanonychia, purplish-black in subungual hematoma, transverse bands in the under surface of plate in true leukonychia, whitish- yellow patches in pseudoleukonychia. In psoriasis, irregular pits, salmon spots are seen whereas in lichen planus onychorrhexis, whitish linear splits and pterygium are observed. Eczema shows pits with lusterless surface. In Darier's disease, characteristic alternate white and red bands are present. Lichen striatus shows longitudinal erythematous bands and ridging. Red dots with white halos are characteristics in warts. Onychomycosis shows 'aurora borealis' pattern and white opaque and friable spots. Bowen's disease shows white scales with red dots. 'Woodworm appearance' and keratotic mass are seen in onychomatricoma and respectively. Squamous cell carcinoma reveals destruction of nail plate and glomus tumor demonstrates pinkish blush. In connective tissue diseases, characteristic changes are present nail fold capillaries. Onychoscopy assists in the analysis and differentiation of many dermatoses which affect nail unit with similar clinical manifestations.

Macroscopic and dermoscopic evaluation used to differentiate subungual haemorrhage from melanocytic lesions

INTRODUCTION Subungual haemorrhage describes blood located between the nail matrix and nail plate caused by trauma. Lack of recalled trauma and long duration of nail pigmentation results in specialist referrals to rule out malignant pathology. AIM This report aims to describe the macroscopic and dermoscopic characteristics of subungual haemorrhage and to highlight its clinical differentiation from melanocytic lesions. METHODS Ninety-eight nails were assessed. Pigmentation in fifty-nine was due to subungual haemorrhage and was melanocytic in the remainder (identified by a longitudinal pigmented band). RESULTS Pigmentation in subungual haemorrhage had a clear proximal margin (73%) and the dermoscopic pattern was homogenous (97%), globular (78%) or streaky (34%). Features included peripheral fading (68%) and periungual haemorrhage (5%). Malignancy could be excluded in these cases by careful clinical evaluation. DISCUSSION A combination of macroscopic and dermoscopic characteristics help make a confident diagnosis of subungual haemorrhage. A two-stage process can aid clinical diagnosis by looking for known features of subungual haemorrhage and identifying absence of malignant features.

Optical coherence tomography in diagnostics of small choroidal melanoma

To determine signs of small choroidal melanoma with different pigmentation using enhanced depth imaging optical coherence tomography (EDI-OCT). The study included 344 patients with small choroidal melanoma with different pigmentation examined using EDI-OCT: 1st group - pigmented melanoma (228 eyes), 2nd group - low pigmented (65 eyes), and 3rd group - amelanotic (51 eyes). In pigmented small choroidal melanomas - elevation of choroidal profile towards vitreous, compression of choriocapillaries with a narrow even 'belt' and a 'shadow' effect; thinning, defects in Bruch's membrane; thickening of the retina above the tumor, lobulated photoreceptors; intra- and subretinal exudate (diffuse, cystic edema, neuroepithelial detachment); defects and detachment of pigment epithelium with hyperreflective foci, disorganization of the pigment with the formation of hyperreflective foci at different retinal levels. In low-pigmented small choroidal melanomas - elevation of choroidal profile towards vitreous, visualized inner surface of the sclera, 'excavation' of the choroid, enlarged choriocapillaries, contour of tumor; thickening of the retina, accumulation of intra- and subretinal exudate (local neuroepithelial detachments); disorganization of the pigment in pigment epithelium with hyperreflective foci in the outer retinal layers. In amelanotic small choroidal melanomas - elevation of choroidal profile towards vitreous, visualized inner surface of the sclera, 'excavation' of the choroid; contouring of choriocapillaries, longitudinal hyperreflective bands in the tumoral stroma, smoothness of the Bruch`s membrane, structural losses of photoreceptors; thickening of the retina (neuroepithelial detachment, diffuse edema); uneven thickening of pigment epithelium. EDI-OCT can help identify microstructural changes in the choroid and adjacent retina in small choroidal melanomas with different degrees of pigmentation, suggesting at the early stages a more aggressive course of the tumoral process affecting the prognosis of the disease. In addition, identification of the microstructure and degree of pigmentation of initial choroidal melanomas is necessary for planning an organ-preserving treatment.

Melanonychia: Etiology, Diagnosis, and Treatment.

Melanonychia is a very worrisome entity for most patients. It is characterized by brownish black discoloration of nail plate and is a common cause of nail plate pigmentation. The aetiology of melanonychia ranges from more common benign causes to less common invasive and in situ melanomas. Melanonychia especially in a longitudinal band form can be due to both local and systemic causes. An understanding of the epidemiology, pathophysiology and clinical details is necessary for adequate patient care and counseling. It not only helps in the early recognition of melanoma but also prevents unnecessary invasive work up in cases with benign etiology. An early diagnosis of malignant lesion is the key to favourable outcome. Though there are no established guidelines or algorithms for evaluating melanonychia, a systematic stepwise approach has been suggested to arrive at a probable etiology. We, hereby, review the aetiology, clinical features, diagnostic modalities and management protocol for melanonychia.

Au@Ag Core/Shell Nanorods Based Colorimetric Assay for the Rapid and Selective Detection of Cyanide Anions

A colorimetric assay based on Au@Ag core/shell nanorods was developed to rapidly determine cyanide in aqueous solution. The aspect ratios of Au@Ag core/shell nanorods were changed with the dissolution of metals in cyanide solution, which led to the decrease of Ag shell absorption spectra and the blue shift of longitudinal plasmon absorption band of Au core, as well as the color change of Au@Ag core/shell nanorods. In contrast to spherical Au@Ag nanoparticles with less sample analysis time (1 min per sample), the distinguish ability of this assay was proven to be higher. Under optimal conditions, the developed colorimetric assay gave a linear range of 1–200 μM for cyanide in water solution and a naked-eye detection limit of 0.5 μM. On the side, the colorimetric assay exhibited high selectivity towards cyanide over other common anions. The developed Au@Ag nanorods probes have been successfully applied to determine the level of cyanide in local lake, river and industrial water samples.

Skeletal Nets of the Ediacaran Fronds

The Ediacara fauna is traditionally regarded as the first complex, diverse and widespread macroscopic life. The uncertainty of systematic position of its members has led to very different views on the early evolution of metazoans. In part, this may be due to a lack of data on sclerotization: a hard skeleton is a part of the archetype of the most taxa known from the fossil record, whereas the Ediacara fauna as a whole is most often considered soft-bodied, which complicates comparison. Here we report the Late Precambrian frond-like fossils (Petalonamae) from the Vendian assemblage of the Southeastern White Sea area (∼555.3 Ma), which show evidence of elaborate skeleton composed of a regular meshwork reinforced by dense longitudinal and circular bands. Judging from the nature of preservation and the dynamics of the environment Ediacaran fronds secreted a relatively rigid but flexible skeleton. The fact that frond-like Petalonamae had a supporting structure similar to that of sponges and cnidarians seems to be a powerful argument in favor of their metazoan affinity. The new observations indicated also that the widespread skeletonization had occurred long before the “Cambrian skeletal revolution”.

Seasonality of surface stirring by geostrophic flows in the Bay of Bengal

Stirring of passive tracers in the Bay of Bengal driven by altimetry derived daily geostrophic surface currents, is studied on subseasonal timescales. To begin with, Hovmöller plots, wavenumber-frequency diagrams and power spectra confirm the multiscale nature of the flow. Advection of latitudinal and longitudinal bands highlights the chaotic nature of stirring in the Bay via repeated straining and filamentation of the tracer field. An immediate finding is that stirring is local, i.e. of the scale of the eddies, and does not span the entire basin. Further, stirring rates are enhanced along the coast of the Bay and are relatively higher in the pre- and post-monsoonal seasons. Indeed, Finite Time Lyapunov Exponent (FTLE) and Finite Size Lyapunov Exponent (FSLE) maps in all the seasons are patchy with minima scattered through the interior of the Bay. Further, these maps bring out a seasonal cycle wherein rapid stirring progressively moves from the northern to southern Bay during pre- and post-monsoonal periods, respectively. The non-uniform stirring of the Bay is reflected in long tailed probability density functions of FTLEs, that become more stretched for longer time intervals. Quantitatively, advection for a week shows the mean FTLE lies between 0.13±0.07 day−1, while extremes reach almost 0.6 day−1. Averaged over the Bay, Relative dispersion initially grows exponentially, followed by a power-law at scales between approximately 100 and 250 km, which finally transitions to an eddy-diffusive regime. Quantitatively, below 250 km, a scale dependent diffusion coefficient is extracted that behaves as a power-law with cluster size, while above 250 km, eddy-diffusivities range from 6×103−1.6×104 m2s−1 in different regions of the Bay. These estimates provide a useful guide for resolution dependent diffusivities in numerical models that hope to properly represent surface stirring in the Bay.

Rare palaeomagnetic evidence of long-term mantle control of the geodynamo and possible role of the NAD field in the reversal process

SUMMARY The degree to which the lowermost mantle influences behaviour of the geodynamo has been debated over the past quarter century. Our analysis of a comprehensive set of 17 Cenozoic palaeomagnetic transitional field records obtained from lavas in the Southern Hemisphere provides robust evidence of stable mantle control since the Pliocene. The records come from a region where—given a significantly weakened axial dipole—the magnetic field today would be largely controlled by the non-axial dipole (NAD) flux patch currently emanating from Earth's outer core beneath western Australia. The palaeomagnetic recording sites from west to east include the south Indian Ocean, eastern Australia, New Zealand and French Polynesia. The analysed records contain from 2 to 26 sequential transitional virtual geomagnetic poles (VGPs). 10 of the 17 records supply at least one VGP within a narrow longitudinal band 10°-wide between 60°S and the equator, centred along 102.4°E. That is, transitional data from 59 per cent of the Cenozoic recordings are found to reside in a region that encompasses a mere 2.8 per cent of the VGP transitional area on Earth's surface. A robust Monte Carlo approach applied to this data set, one that takes into account the number of transitional VGPs contained in each record, finds this result highly improbable (p-value = 0.0006). The present-day pattern of vertical flux at the core–mantle boundary shows an anomalously strong, thin Southern Hemisphere longitudinal band off the west coast of Australia that strikingly coincides with this unusual palaeomagnetic finding. We conclude with a high degree of confidence that this band of flux has remained virtually unmoved for at least the past 3 Myr. Seemingly independent of the behaviour of the axial dipole, our findings indicate that it has dominated the magnetic field over an area of considerable size during attempts by the geodynamo to reverse polarity.

Pristimantis tinguichaca Brito, Ojala-Barbour, Batallas & Almendariz, 2016 (Anura, Strabomantidae): range extension and notes on variation in color pattern

In this paper we extend the known distribution of the endemic and recently described Pristimantis tinguichaca Brito et al. 2016, a terrestrial robber frog characterized by its beige and brown to dark-brown dorsal coloration, flanks with longitudinal or diagonal cream-coloured bands which are separated by brown, and reddish iris. The new records, based on two specimens collected from the Cerro Candelaria and Cerro Mayordomo reserves of Fundación Ecominga in the upper Pastaza River watershed, Tungurahua province, east-central Ecuador, represent the northern limit of the species and extend this species to the Llanganates–Sangay ecological corridor.

Polyclad fauna of Agatti Island, Lakshadweep, India: new records and description of two new species.

The present paper deals with the first study of polyclad fauna from Agatti Island, Lakshadweep. Through this study, Pseudobiceors apricus, Pseudobiceros hymanae and Pseudoceros bolool are recorded for the first time from Lakshadweep waters while Pseudoceros bicolor is recorded for the first time from Indian waters. Description of two new species, Pseudoceros agattiensis sp. nov. and Pseuodoceros stellans sp. nov. is also provided with good quality photographs of external and internal details. Pseudoceros agattiensis sp. nov. is characterized by a brown to black background colour, with minute white spots, marginal band thick and black with minute white spots present at very edge of the margin, three dorsal longitudinal white bands, out of which, two are laterally branched. Pseudoceros stellans sp. nov. displays a brown background colour with a black marginal band and completely covered with lighter microdots and a unique pattern of white dorsal blotches. This study adds to the knowledge of Indian polyclads, which are still an understudied group from Indian waters.

Nanoplasmonic sensing of NADH by inhibiting the oxidative etching of gold nanorods

The plasmonic spectral sensing method based on the etching of gold nanorods has been a powerful tool in the field of biomedical detection. Among the plasmonic etching sensors, the most popular sensing strategy is the “positive oxidative etching” plasmonic sensor that is based on plasmon blue-shifting due to nanorod shortening. In this study, we proposed a nanoplasmonic detection of dihydronicotinamide adenine dinucleotide (NADH) based on negative oxidative etching: NADH-mediated inhibition of H2O2 induced gold nanorods etching. In the presence of NADH, the bromine intermediates (Br3− and Br2) used for etching gold nanorods were reduced and consumed, inhibiting the etching rate and resulting in a small blue-shift of the longitudinal plasmon band (LPB). This shift can be utilized to sense the presence of NADH. Under the optimal reaction conditions, the LPB difference (Δλ) of etched gold nanorods and the concentration of NADH had a good linear relationship in the range of 0–4.9 × 10−6 mol/L. The nanoplasmonic sensing showed a satisfactory preference for NADH over other common substances tested. It was successfully applied to the detection of NADH in PBS solution. This system provides a platform for the detection of targets in NADH-generated enzyme catalysis.

Description of a new Pergalumna (Acari: Oribatida: Galumnidae) species from Mexico and its postembryonic development.

A new species of Pergalumna from soil and litter was reared in laboratory and a description of adult and juveniles is provided. Adults are characterized by having bands of striae in the posterior part of notogaster, the interlamellar seta are longer than all other prodorsal setae and the lenticular area covers most of the prodorsum. It differs from Pergalumna boliviana by having long interlamellar seta, bigger ellipsoidal porose area Aa and the presence of A2; it differs from Pergalumna paraboliviana by the shape of porose areas; i.e. Aa being ellipsoidal and big, A1 is the smallest, Ap is absent and there are longitudinal striate bands on the prodorsum and ventral plate.

Plasmonic nanobiosensor based on Au nanorods with improved sensitivity: A comparative study for two different configurations

Biosensors presenting high sensitivity for the detection of biomolecules are very promising for diseases diagnosis. Nowadays, there is a need for the development of biosensors with fast, trustworthy diagnosis and mostly with low cost, mainly for applications in developing countries. Label-free plasmonic biosensors are good candidates to reach out all these characteristics due to the possibility of spectral tunability, fast sensor response, real-time detection, strong enhancement of the local electric field and excellent adaptability to assemble different nanobiotechnology architectures. In this paper, two different configurations for LSPR based biosensor were developed by using solution-phase gold nanorods (S–P-AuNRs) and AuNRs-chip. The LSPR sensitivities were evaluated by monitoring shifts in the longitudinal plasmon band with changes in the refractive index of the medium surrounding the nanoparticles. AuNRs-chip presented higher sensitivity of 297 nm RIU−1 (refractive index unit) against 196 nm RIU−1 for S–P-AuNRs. Figure of merit (FOM) for AuNRs-chip and S–P-AuNRs were 3.0 and 2.2 RIU−1, respectively. This result was assigned to the coupling of the lower energy longitudinal LSPR mode of propagation for AuNRs-chip among nearby nanoparticles in the film. In addition, an improvement of at least 18% in sensitivity was obtained comparing to others AuNRs based assay with similar aspect ratio. FOM is more appropriate to compare different approaches, in this case, the proposed biosensor reached improvements of at least 114%, presenting higher values even when compared to AuNRs of higher aspect ratio. As a proof of concept, AuNRs surface was chemically modified using mercaptoundecanoic acid followed activation with ethylcarbodiimide and N-hidroxysuccinimide to allow the interaction between Bovine Serum Albumin (BSA) antibody and correspondent antigen. Both configurations studied resulted in efficient plasmonic biosensors, presenting high sensitivity for changes in the refractive index and for surface binding with anti-BSA.

Scolopsislacrima, a new species of monocle bream (Teleostei, Perciformes, Nemipteridae) from New Caledonia.

The new monocle bream Scolopsislacrimasp. nov. is described from a single specimen (213.6 mm standard length) collected from Grande-Terre Island, New Caledonia. The new species closely resembles S.meridiana, both species having the upper part of the pectoral-fin base with reddish blotch when fresh, two bands across the top of the snout, a dorsal scaled area on the head reaching anteriorly to between the anterior margin of the eye and anterior nostril, a similar number of lateral-line scales, and absence of a small antrorse spine below the eye. However, S.lacrimasp. nov. is distinguished from S.meridiana by having diagonal lines on the body absent (vs. 18–20 diagonal lines in the latter), a dark longitudinal band below the lateral line (vs. longitudinal lines absent), the caudal fin central area not patterned (vs. with several dark horizontal lines), a narrower body and shallower caudal peduncle.

Hip Adductor Intramuscular Nerve Distribution Pattern of Children: A Guide for BTX-A Treatment to Muscle Spasticity in Cerebral Palsy.

To investigate the intramuscular nerve distribution pattern in the hip adductors of children and to precisely locate the injection site for botulinum toxin type A (BTX-A) as a treatment for hip adductor spasticity in children with cerebral palsy. Modified Sihler's whole mount nerve staining technique was employed to observe the distribution of intramuscular nerves in hip adductors of children and to further locate zones where terminal nerves are concentrated. The terminal nerves of the adductor longus appeared in a longitudinal distribution band parallel to the line between the upper 1/3 point of the lateral boundary and the center of the medial boundary. In adductor brevis, the terminal nerves showed a sheet-like distribution with a nerve dense area located in the middle of the muscle belly that extends from the upper-inner region to the lower-outer region. Gracilis showed a dense area of terminal nerves in the middle of the muscle belly, closer to the posterior boundary. In adductor magnus, the dense area of terminal nerves showed a sheet-like distribution in the middle and lower region of the muscle belly. The dense area of terminal nerves in the pectineus was located in the middle of the muscle belly. This study is the first to systematically investigate the intramuscular nerve distribution pattern in the hip adductors. The results indicated that the best targets for BTX-A injection, when treating spasticity, are the dense regions of terminal nerves described above.

Topological edge modeling and localization of protected interface modes in 1D phononic crystals for longitudinal and bending elastic waves

In this paper, a theoretical and numerical study on the band transition and topological interface modes with topological phases is established for a 1D periodic cross-sections of phononic crystals (PCs) consisting of circular aluminum beams. The longitudinal waves band structure is studied by the transfer matrix method while the modified transfer matrix method with the Euler-Bernoulli beam model is established for studying the dispersion relation of bending waves. The initial five Bloch bands are presented and finite element validation with good agreement between the models has been reported. The variation in geometric parameters result into band transitions and accidental degeneracies has been observed at the lower and higher wave modes. The geometric phases of the Bloch bands are determined through numerical calculations of the Zak phase where symmetric and unsymmetric edge-mode states are distinguished. The Dirac cone plots indicate that band transitions and exchange in wave mode polarizations are successive in nature and their existence increases with increasing bandgaps. Thus, the number of mode transition frequency increases. Geometric phases provide information about the interface modes. These interface modes are generated when mode transition frequency is common between the bandgaps of a topological PC and they are validated through finite unit cell based frequency response study. Furthermore, through a time transient analysis the passband, bandgap and interface mode frequencies are differentiated and localization with robustness of interface mode is reported through the Q-factor calculation and spatial distribution of displacement fields. The effects of damping and material loss factor on the interface modes are also considered. In conclusion, this study mainly focuses on the existence of multiple interface modes for a topological PC at the lower and higher frequency regions that it can be further extended for solving multiple vibration related engineering problems.

Monodisperse Gold Nanorods for High-Pressure Refractive Index Sensing.

The effects of hydrostatic pressure on the surface plasmon resonances (SPRs) of aqueous dispersions of monodisperse gold nanorods (AuNRs)were determined up to 9 GPa. The ultranarrow longitudinal SPR band of monodisperse AuNRs allows us to monitor a gradual red shift with pressure, which shows abrupt jumps at the liquid to ice phase VI and ice phase VII transitions. Despite solidifying at low pressure (∼1.8 GPa), water displays a regime of quasi-hydrostaticity in said phases VI and VII, up to ca. 5 GPa. Above this pressure, nonhydrostatic effects manifest themselves through broadening of the SPR bands, but barely any effect is observed on the position of the surface plasmon mode. The variation in the SPR peak wavelength with pressure allowed us to determine the pressure dependence of the refractive index of water. Unlike Brillouin scattering or interferometric techniques, this plasmon-spectroscopy-based method leads to a more direct determination of the refractive index, which is well described empirically by Murnaghan-type equations in the three explored phases. We report herein the obtained analytical functions providing the pressure dependence of refractive index in the liquid, ice VI, and ice VII phases of water.

Auxosporulation in Chaetoceros acadianus sp. nov. (Bacillariophyceae), a new member of the Section Compressa

ABSTRACTWe document the fine structure of auxospores in a Chaetoceros species isolated from the Acadian coast of New Brunswick, Canada. Auxospore development in this species occurs in a terminal rather than lateral position, a characteristic never before observed in this genus. Our observations suggest that auxosporulation was uniparental, probably an extreme form of autogamy with sister nuclei fusing following meiosis II. Mature auxospores were adze-shaped to sub-globular and contained both scales and transverse perizonia in their walls. The transverse perizonial band structure was similar to longitudinal perizonial bands found in other species of Chaetoceros and differed from the pinnate bands of pennate transverse perizonia, which consisted of a central rib and bilateral fimbria. Instead, the band structure in C. acadianus was more similar to unilateral fimbriate bands in cymatosiroids. We also propose that our diatom represents a species new to science and is a member of the Chaetoceros Section Compressa. We provide its morphological, molecular and reproductive characterization.

Chemical Transformation of Nanorods to Nanowires: Reversible Growth and Dissolution of Anisotropic Gold Nanostructures.

This manuscript describes a reversible wet chemical process for the tip-selective one-dimensional (1D) growth and dissolution of gold nanorods (AuNRs) and gold nanowires (AuNWs). Tip-selective dissolution was achieved by oxidation of AuNRs with a Au(III)/CTAB complex, whereas the growth of AuNRs was carried out by the reduction of Au(I) ions on the AuNR surface with a mild reducing agent, ascorbic acid (AA). Both the dissolution and growth processes are highly tip selective and proceed exclusively in one dimension. A decrease in the aspect ratio (AR) of AuNRs during the dissolution resulted in a blue shift in the longitudinal plasmon band (LPB) position, and red shifts in the LPB position were achieved by increasing the AR by 1D growth of AuNRs. Both growth and dissolution processes are fully controllable and can be stopped and resumed at any given time when the desired AR and/or LPB position is achieved. In addition, the tip-selective 1D growth of AuNRs can be continued with the additional supply of Au(I)/CTAB/AA solution to produce extremely long AuNWs.