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1.
Neurogenetics ; 25(2): 119-130, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38388889

RESUMO

The terms developmental epileptic encephalopathy with spike-and-wave activation in sleep (DEE-SWAS) and epileptic encephalopathy with spike-and-wave activation in sleep (EE-SWAS) designate a spectrum of conditions that are typified by different combinations of motor, cognitive, language, and behavioral regression linked to robust spike-and-wave activity during sleep. In this study, we aimed at describing the clinical and molecular findings in "(developmental) epileptic encephalopathy with spike-and-wave activation in sleep" (D)EE-SWAS) patients as well as at contributing to the genetic etiologic spectrum of (D)EE-SWAS. Single nucleotide polymorphism (SNP) array and whole-exome sequencing (WES) techniques were used to determine the underlying genetic etiologies. Of the 24 patients included in the study, 8 (33%) were female and 16 (67%) were male. The median age at onset of the first seizure was 4 years and the median age at diagnosis of (D)EE-SWAS was 5 years. Of the 24 cases included in the study, 13 were compatible with the clinical diagnosis of DEE-SWAS and 11 were compatible with the clinical diagnosis of EE-SWAS. Abnormal perinatal history was present in four cases (17%), and two cases (8%) had a family history of epilepsy. Approximately two-thirds (63%) of all patients had abnormalities detected on brain computerized tomography/magnetic resonance (CT/MR) imaging. After SNP array and WES analysis, the genetic etiology was revealed in 7 out of 24 (29%) cases. Three of the variants detected were novel (SLC12A5, DLG4, SLC9A6). This study revealed for the first time that Smith-Magenis syndrome, SCN8A-related DEE type 13 and SLC12A5 gene variation are involved in the genetic etiology of (D)EE-SWAS. (D)EE-SWAS is a genetically diverse disorder with underlying copy number variations and single-gene abnormalities. In the current investigation, rare novel variations in genes known to be related to (D)EE-SWAS and not previously reported genes to be related to (D)EE-SWAS were discovered, adding to the molecular genetic spectrum. Molecular etiology enables the patient and family to receive thorough and accurate genetic counseling as well as a personalized medicine approach.


Assuntos
Sequenciamento do Exoma , Sono , Humanos , Masculino , Feminino , Criança , Turquia , Pré-Escolar , Sono/genética , Polimorfismo de Nucleotídeo Único , Eletroencefalografia , Espasmos Infantis/genética , Lactente , Estudos de Coortes , Epilepsia/genética , Adolescente
2.
Clin Endocrinol (Oxf) ; 101(2): 108-113, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38796770

RESUMO

BACKGROUND: Newborn screening (NBS) reduces the risk of mortality in congenital adrenal hyperplasia (CAH), mainly due to the salt-wasting form of 21-hydroxylase deficiency. There is limited knowledge regarding the results of NBS in non-CAH primary adrenal insufficiency (non-CAH PAI). PATIENTS AND METHODS: Clinical and NBS for CAH data of neonates who were diagnosed with non-CAH PAI between January and December 2022 were examined. RESULTS: Patients (n = 6, 4 females) were presented with severe hyperpigmentation (n = 6), hypoglycemia (n = 4), hyponatremia (n = 3), hyperkalemia (n = 1), respiratory distress syndrome (n = 1) between 3rd hour to 2 months of life. All had normal NBS results. The median first-tier 17-hydroxyprogesterone (17OHP) concentration in NBS for CAH was 0.14 ng/mL (range; 0.05-0.85). Molecular studies revealed biallelic mutations in the MC2R (n = 4; 3 homozygous, 1 compound heterozygous), MRAP (n = 1) and STAR (n = 1) genes. Glucocorticoid with or without mineralocorticoid replacement was initiated once the diagnosis of non-CAH PAI was established. CONCLUSION: Neonates with non-CAH PAI have always normal NBS due to persistently low 17OHP, even when these newborn infants are severely symptomatic for adrenal insufficiency. Clinicians should be alert for signs of adrenal insufficiency in neonates, even if the patient has a 'normal' screening for CAH, so as not to delay diagnosis and treatment. This fact should be kept in mind particularly in countries where these conditions are more common than elsewhere.


Assuntos
Hiperplasia Suprarrenal Congênita , Insuficiência Adrenal , Triagem Neonatal , Humanos , Recém-Nascido , Triagem Neonatal/métodos , Feminino , Masculino , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/genética , Hiperplasia Suprarrenal Congênita/sangue , Insuficiência Adrenal/diagnóstico , Insuficiência Adrenal/sangue , 17-alfa-Hidroxiprogesterona/sangue , Mutação
3.
Artigo em Inglês | MEDLINE | ID: mdl-38324408

RESUMO

OBJECTIVE: Autosomal-recessive hypophosphataemic rickets type 2 (ARHR2) is a rare disease that is reported in survivors of generalized arterial calcification of infancy (GACI). DESIGN, PATIENTS AND MEASUREMENT: The objective of this study was to characterize a multicenter paediatric cohort with ARHR2 due to ectonucleotide pyrophosphatase/phosphodiesterase family member 1 (ENPP1) deficiency and with a diagnosis of GACI or GACI-related findings. The clinical, biochemical and genetic characteristics of the patients were retrospectively retrieved. RESULTS: We identified 18 patients from 13 families diagnosed with ARHR2. Fifteen of the patients had an ENPP1 variation confirmed with genetic analyses, and three were siblings of one of these patients, who had clinically diagnosed hypophosphataemic rickets (HRs) with the same presentation. From nine centres, 18 patients, of whom 12 (66.7%) were females, were included in the study. The mean age at diagnosis was 4.2 ± 2.2 (1.6-9) years. The most frequently reported clinical findings on admission were limb deformities (66.6%) and short stature (44.4%). At diagnosis, the mean height SD was -2.2 ± 1.3. Five of the patients were diagnosed with GACI in the neonatal period and treated with bisphosphonates. Other patients were initially diagnosed with ARHR2, but after the detection of a biallelic variant in the ENPP1 gene, it was understood that they previously had clinical findings associated with GACI. Three patients had hearing loss, and two had cervical fusion. After the treatment of HRs, one patient developed calcification, and one developed intimal proliferation. CONCLUSION: ARHR2 represents one manifestation of ENPP1 deficiency that usually manifests later in life than GACI. The history of calcifications or comorbidities that might be associated with GACI will facilitate the diagnosis in patients with ARHR2, and patients receiving calcitriol and phosphate medication should be carefully monitored for signs of calcification or intimal proliferation.

4.
Pediatr Allergy Immunol ; 35(6): e14171, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38860449

RESUMO

BACKGROUND: Artemis deficiency is an autosomal recessive disorder characterized by a combined immunodeficiency with increased cellular radiosensitivity. In this review, the clinical and genetic characteristics of 15 patients with DCLRE1C variants are presented. METHODS: The demographic, clinical, immunologic, and genetic characteristics of patients with confirmed DCLRE1C variants diagnosed between 2013 and 2023 were collected retrospectively. Three patients were evaluated for radiosensitivity by the Comet assay, compared with age- and sex-matched healthy control. RESULTS: Seven patients who had severe infections in the first 6 months of life were diagnosed with T-B-NK+ SCID (severe combined immunodeficiency). Among them, four individuals underwent transplantation, and one of those died due to post-transplant complications in early life. Eight patients had hypomorphic variants. Half of them were awaiting a suitable donor, while the other half had already undergone transplantation. The majority of patients were born into a consanguineous family (93.3%). Most patients had recurrent sinopulmonary infections (73.3%), and one patient had no other infection than an acute respiratory infection before diagnosis. Two patients (13.3%) had autoimmunity in the form of autoimmune hemolytic anemia. Growth retardation was observed in only one patient (6.6%), and no malignancy was detected in the surviving 11 patients during the median (IQR) of 21.5 (12-45) months of follow-up. Three patients who had novel variants exhibited increased radiosensitivity and compromised DNA repair, providing a potential vulnerability to malignant transformation. CONCLUSION: Early diagnosis, radiation avoidance, and careful preparation for transplantation contribute to minimizing complications, enhancing life expectancy, and improving the patient's quality of life.


Assuntos
Proteínas de Ligação a DNA , Tolerância a Radiação , Imunodeficiência Combinada Severa , Humanos , Tolerância a Radiação/genética , Masculino , Feminino , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/terapia , Lactente , Proteínas de Ligação a DNA/genética , Pré-Escolar , Estudos Retrospectivos , Endonucleases/genética , Proteínas Nucleares/genética , Criança , Estudos de Coortes
5.
Clin Immunol ; 255: 109757, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37689091

RESUMO

Paired box 1 (PAX1) deficiency has been reported in a small number of patients diagnosed with otofaciocervical syndrome type 2 (OFCS2). We described six new patients who demonstrated variable clinical penetrance. Reduced transcriptional activity of pathogenic variants confirmed partial or complete PAX1 deficiency. Thymic aplasia and hypoplasia were associated with impaired T cell immunity. Corrective treatment was required in 4/6 patients. Hematopoietic stem cell transplantation resulted in poor immune reconstitution with absent naïve T cells, contrasting with the superior recovery of T cell immunity after thymus transplantation. Normal ex vivo differentiation of PAX1-deficient CD34+ cells into mature T cells demonstrated the absence of a hematopoietic cell-intrinsic defect. New overlapping features with DiGeorge syndrome included primary hypoparathyroidism (n = 5) and congenital heart defects (n = 2), in line with PAX1 expression during early embryogenesis. Our results highlight new features of PAX1 deficiency, which are relevant to improving early diagnosis and identifying patients requiring corrective treatment.


Assuntos
Fatores de Transcrição Box Pareados , Imunodeficiência Combinada Severa , Humanos , Fatores de Transcrição Box Pareados/genética , Fenótipo , Linfócitos T , Timo , Imunodeficiência Combinada Severa/genética
6.
Langmuir ; 39(26): 8996-9006, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37337368

RESUMO

Two-dimensional polystyrene sphere opals are important materials for nanotechnology applications and fundamental nanoscience research. They are a facile and inexpensive nanofabrication tool, but the quality factor of these opals has drastic differences between reports. Additives like ethanol, ions, and organic molecules in the aqueous particle spreading solution are known to affect the quality factor and growth efficiency of the produced opals. However, a systematic study on the effect and optimization of some of the most effective additives has not been reported until now. Here, we investigate the influence of additives on the growth efficiency and quality factor of such monolayers formed at the air-water interface without the use of a Langmuir-Blodgett trough. The additives induced large variations in the monolayer quality factor and growth efficiency, and we found that the ideal additive content of the spreading agents is 30 wt % < cethanol < 70 wt %, 0 < cH2SO4 < 30.5 mM, and 0 < csty < 255.0 mM. This study provides a guideline for the rational composition and additive content of the spreading solution to obtain high-quality two-dimensional opals for further applications in nanofabrication and photonics and will enable researchers and application engineers to produce standardized nanofabrication materials.

7.
Nanotechnology ; 33(6)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34710859

RESUMO

Until now, the growth of periodic vertically aligned multi-walled carbon nanotube (VA-MWCNT) arrays was dependent on at least one lithography step during fabrication. Here, we demonstrate a lithography-free fabrication method to grow hexagonal arrays of self-standing VA-MWCNTs with tunable pitch and MWCNT size. The MWCNTs are synthesized by plasma enhanced chemical vapor deposition (PECVD) from Ni catalyst particles. Template guided dewetting of a thin Ni film on a hexagonally close-packed silica particle monolayer provides periodically distributed Ni catalyst particles as seeds for the growth of the periodic MWCNT arrays. The diameter of the silica particles directly controls the pitch of the periodic VA-MWCNT arrays from 600 nm to as small as 160 nm. The diameter and length of the individual MWCNTs can also be readily adjusted and are a function of the Ni particle size and PECVD time. This unique method of lithography-free growth of periodic VA-MWCNT arrays can be utilized for the fabrication of large-scale biomimetic materials.

8.
Opt Express ; 28(21): 31425-31435, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33115115

RESUMO

Ultrasensitive sensors of various physical properties can be based on percolation systems, e.g., insulating media filled with nearly touching conducting particles. Such a system at its percolation threshold featuring the critical particle concentration, changes drastically its response (electrical conduction, light transmission, etc.) when subjected to an external stimulus. Due to the critical nature of this threshold, a given state at the threshold is typically very unstable. However, stability can be restored without significantly sacrificing the structure sensitivity by forming weak connections between the conducting particles. In this work, we employed nano-bridged nanosphere lithography to produce such a weakly connected percolation system. It consists of two coupled quasi-Babinet complementary arrays, one with weakly connected, and the other with disconnected metallic islands. We demonstrate via experiment and simulation that the physics of this plasmonic system is non-trivial, and leads to the extraordinary optical transmission at narrowly defined peaks sensitive to system parameters, with surface plasmons mediating this process. Thus, our system is a potential candidate for percolation effect based sensor applications. Promising detection schemes could be based on these effects.

9.
Chemistry ; 26(68): 16057-16065, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-32667107

RESUMO

The practical application of Li-S batteries demands low cell balance (Licapacity /Scapacity ), which involves uniform Li growth, restrained shuttle effect, and fast redox reaction kinetics of S species simultaneously. Herein, with the aid of W2 C nanocrystals, a freestanding 3D current collector is applied as both Li and S hosts owing to its lithiophilic and sulfilic property. On the one hand, the highly conductive W2 C can reduce Li nucleation overpotentials, thus guiding uniform Li nucleation and deposition to suppress Li dendrite growth. On the other hand, the polar W2 C with catalytic effect can enhance the chemisorption affinity to lithium polysulfides (LiPSs) and guarantee fast redox kinetics to restrain S species in cathode region and promote the utilization of S. Surprisingly, a full Li-S battery with ultralow cell balance of 1.5:1 and high sulfur loading of 6.06 mg cm-2 shows obvious redox plateaus of S and maintains high reversible specific capacity of 1020 mAh g-1 (6.2 mAh cm-2 ) after 200 cycles. This work may shed new sights on the facile design of full Li-S battery with low excessive Li supply.

10.
Nanotechnology ; 31(24): 245302, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32126530

RESUMO

We develop nano-bridged nanosphere lithography (NB-NSL), a modification to the widely used conventional nanosphere lithography (NSL). Nano-bridges between polystyrene (PS) spheres of a pristine NSL template are controllably formed in a two-step process: (i) spin-coating of a dilute styrene solution on top of the template, followed by (ii) oxygen plasma etching of the template. We show that the nanobridge dimensions can be precisely tuned by controlling the pre-processing conditions and the plasma etching time. The resulting lithography templates feature control over the shape and size of the apertures, which determine the morphology of the final nano-island arrays after material deposition and template removal. The unique advantage of NB-NSL is that PS particle templates based on a single PS particle diameter can be utilized for the fabrication of a variation of nano-island shapes and sizes, whereas conventional NSL yields only bowtie-shaped nano-islands, with their size being predetermined by the PS particle diameter of the template.

11.
Opt Express ; 27(16): 22939-22950, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510578

RESUMO

A plasmonic structure with transmission highly tunable in the mid-infrared spectral range is developed. This structure consists of a hexagonal array of metallic discs located on top of silicon pillars protruding through holes in a metallic Babinet complementary film. We reveal with FDTD simulations that changing the hole diameter tunes the main plasmonic resonance frequency of this structure throughout the infrared range. Due to the underlying Babinet physics of these coupled arrays, the spectral width of these plasmonic resonances is strongly reduced, and the higher harmonics are suppressed. Furthermore, we demonstrate that this structure can be easily produced by a combination of the nanosphere lithography and the metal-assisted chemical etching technique.

13.
Opt Express ; 26(1): 338, 2018 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-29328309

RESUMO

This publisher's note amends the author listing of [Opt. Express26, 32792 (2017)].

15.
Am J Hum Genet ; 90(6): 1094-101, 2012 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-22608503

RESUMO

Cantú syndrome is a rare disorder characterized by congenital hypertrichosis, neonatal macrosomia, a distinct osteochondrodysplasia, and cardiomegaly. Using an exome-sequencing approach applied to one proband-parent trio and three unrelated single cases, we identified heterozygous mutations in ABCC9 in all probands. With the inclusion of the remaining cohort of ten individuals with Cantú syndrome, a total of eleven mutations in ABCC9 were found. The de novo occurrence in all six simplex cases in our cohort substantiates the presence of a dominant disease mechanism. All mutations were missense, and several mutations affect Arg1154. This mutation hot spot lies within the second type 1 transmembrane region of this ATP-binding cassette transporter protein, which may suggest an activating mutation. ABCC9 encodes the sulfonylurea receptor (SUR) that forms ATP-sensitive potassium channels (K(ATP) channels) originally shown in cardiac, skeletal, and smooth muscle. Previously, loss-of-function mutations in this gene have been associated with idiopathic dilated cardiomyopathy type 10 (CMD10). These findings identify the genetic basis of Cantú syndrome and suggest that this is a new member of the potassium channelopathies.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Cardiomegalia/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Hipertricose/genética , Mutação , Osteocondrodisplasias/genética , Canais de Potássio Corretores do Fluxo de Internalização/genética , Receptores de Droga/genética , Adolescente , Adulto , Sequência de Bases , Criança , Estudos de Coortes , Fácies , Feminino , Genes Dominantes , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Fenótipo , Canais de Potássio/genética , Análise de Sequência de DNA , Receptores de Sulfonilureias
16.
Small ; 10(20): 4136-41, 2014 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24976434

RESUMO

A novel Au@MnO2 supercapacitor is presented. The sophisticated core-shell architecture combining an Au nanomesh core with a MnO2 shell on a flexible polymeric substrate is demonstrated as an electrode for high performance transparent flexible supercapacitors (TFSCs). Due to their unique structure, high areal/gravimetric capacitance and rate capability for TFSCs are achieved.

17.
Adv Mater ; : e2310822, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38044876

RESUMO

The electrosynthesis of multi-carbon chemicals from excess CO2 is an area of great interest for research and commercial applications. However, improving both the yield of CO2 -to-ethanol conversion and the stability of the catalyst at the same time is proving to be a challenging issue. Here we propose to stabilize active Cu(I) and In dual sites with sulfur defects through an electro-driven intercalation strategy, which leads to the delocalization of electron density that enhances orbital hybridizations between the Cu-C and In-H bonds. Hence, the energy barrier for the rate-limiting *CHO formation step is reduced toward the key *OCHCHO* formation during ethanol production, which is also facilitated by the combined Cu site enabling C-C coupling and In site with a higher oxygen affinity based on both thermodynamic and kinetic calculations. Accordingly, such dual-site catalyst achieves a high partial current density toward ethanol of 409 ± 15 mA/cm2 for over 120 hours. Furthermore, a scaled-up flow cell is assembled with an industrial-relevant current of 5.7 A for over 36 hours, in which the carbon loss is less than 2.5% and single-pass carbon efficiency is around 19%. This article is protected by copyright. All rights reserved.

18.
ACS Nano ; 17(24): 24763-24772, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-37901960

RESUMO

Transparent electrodes are vital for optoelectronic devices, but their development has been constrained by the limitations of existing materials such as indium tin oxide (ITO) and newer alternatives. All face issues of robustness, flexibility, conductivity, and stability in harsh environments. Addressing this challenge, we developed a flexible, low-cost titanium nitride (TiN) nanomesh transparent electrode showcasing exceptional acid-alkali resistance. The TiN nanomesh electrode, created by depositing a TiN coating on a naturally cracked gel film substrate via a sputtering method, maintains a stable electrical performance through thousands of bending cycles. It exhibits outstanding chemical stability, resisting strong acid and alkali corrosion, which is a key hurdle for current electrodes when in contact with acidic/alkaline materials and solvents during device fabrication. This, coupled with superior light transmission and conductivity (88% at 550 nm with a sheet resistance of ∼200 Ω/sq), challenges the reliance on conventional materials. Our TiN nanomesh electrode, successfully applied in electric heaters and electrically controlled thermochromic devices, offers broad potential beyond harsh environment applications. It enables alternative possibilities for the design and fabrication of future optoelectronics for advancements in this pivotal field.

19.
Clin Neurol Neurosurg ; 224: 107560, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36580738

RESUMO

OBJECTIVE: Joubert syndrome is a neurodevelopmental disorder with a distinctive hindbrain malformation called molar tooth sign, causing motor and cognitive impairments. More than 40 genes have been associated with Joubert syndrome. We aim to describe a group of Joubert syndrome patients clinically and genetically emphasizing organ involvement. METHODS: We retrospectively collected clinical information and molecular diagnosis data of 22 patients with Joubert syndrome from multiple facilities. Clinical exome or whole-exome sequencing were performed to identify causal variations in genes. RESULTS: The most common variants were in the CPLANE1, CEP290, and TMEM67 genes, and other causative genes were AHI1, ARMC9, CEP41, CSPP1, HYLS1, KATNIP, KIAA0586, KIF7, RPGRIP1L, including some previously unreported variants in these genes. Multi-systemic organ involvement was observed in nine (40%) patients, with the eye being the most common, including Leber's congenital amaurosis, ptosis, and optic nerve coloboma. Portal hypertension and esophageal varices as liver and polycystic kidney disease and nephronophthisis as kidney involvement was encountered in our patients. The HYLS1 gene, which commonly causes hydrolethalus syndrome 1, was also associated with Joubert syndrome in one of our patients. A mild phenotype with hypophyseal hormone deficiencies without the classical molar tooth sign was observed with compound heterozygous and likely pathogenic variants not reported before in the KATNIP gene. CONCLUSION: Some rare variants that display prominent genetic heterogeneity with variable severity are first reported in our patients. In our study of 22 Joubert syndrome patients, CPLANE1 is the most affected gene, and Joubert syndrome as a ciliopathy is possible without a classical molar tooth sign, like in the KATNIP gene-affected patients.


Assuntos
Anormalidades Múltiplas , Ciliopatias , Anormalidades do Olho , Doenças Renais Císticas , Humanos , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Doenças Renais Císticas/diagnóstico , Doenças Renais Císticas/genética , Cerebelo/anormalidades , Anormalidades do Olho/diagnóstico , Anormalidades do Olho/genética , Retina/patologia , Estudos Retrospectivos , Mutação , Ciliopatias/diagnóstico , Ciliopatias/genética , Ciliopatias/patologia , Proteínas/genética , Antígenos de Neoplasias , Proteínas do Citoesqueleto/genética , Proteínas de Ciclo Celular/genética
20.
Nanoscale ; 15(15): 7077-7085, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-36987591

RESUMO

The luminescence of InxGa1-xN nanowires (NWs) is frequently reported with large red-shifts as compared to the theoretical value expected from the average In content. Both compositional fluctuations and radial built-in fields were considered accountable for this effect, depending on the size, structure, composition, and surrounding medium of the NWs. In the present work, the emission properties of InGaN/GaN NWs grown by plasma-assisted molecular beam epitaxy are investigated in a comprehensive study combining ultraviolet-Raman and photoluminescence spectroscopy (PL) on vertical arrays, polarization-dependent PL on bundles of a few NWs, scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy, and calculations of the band profiles. The roles of inhomogeneous In distribution and radial fields in the context of optical emission properties are addressed. The radial built-in fields are found to be modest, with a maximum surface band bending below 350 meV. On the other hand, variations in the local In content have been observed that give rise to potential fluctuations whose impact on the emission properties is shown to prevail over band-bending effects. Two luminescence bands with large positive and moderate negative polarization ratios of ≈+80% and ≤-60%, respectively, were observed. The red-shift in the luminescence is associated with In-rich inclusions in the NWs due to thermodynamic decomposition during growth. The negative polarization anisotropy is suggested to result from spontaneously formed superlattices in the In-rich regions of the NWs. The NWs show a preferred orthogonal absorption due to the dielectric boundary conditions and highlight the extreme sensitivity of these structures towards light polarization.

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