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The relative overexpression of Coxsackie and adenoviral receptor (CAR) predisposes children to viral myocarditis. As the foot and mouth disease virus (FMDV) causes fatal myocarditis in calves, lambs, and piglets and belongs to the same family as the Coxsackie virus, we investigated the role of CAR in FMDV induced myocarditis in the suckling mice model. Swiss albino suckling mice of 5 days (n = 24) were divided into two equal groups. One group was inoculated with suckling mice adapted FMDV serotype O at 10 LD50, while the other group served as uninfected control. In addition, adult mice (n = 12) served as the control for age related CAR expression and lack of pathogenicity to FMDV. The establishment of myocarditis was confirmed by histopathological changes typical of myocarditis along with immunolocalization of FMDV antigens in the heart of suckling mice. The FMDV inoculated suckling mice group showed a significant upregulation of CAR transcripts by 2.5 folds, overexpression of CAR protein by densitometric analysis of immunoblots, and intense immunolocalization of CAR in the sarcolemma and intercalated discs of cardiomyocytes as compared to the uninfected suckling mice group and adult mice. It was concluded that FMDV infection induced overexpression of CAR in the myocardium of suckling mice.
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Vírus da Febre Aftosa , Febre Aftosa , Miocardite , Criança , Animais , Camundongos , Ovinos , Bovinos , Humanos , Suínos , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus , MiocárdioRESUMO
AIM: To compare peri-operative outcomes of skin closure with octyl cyanoacrylate (OCA) skin adhesive (Dermabond) with or without subcuticular sutures after deep dermal suturing for implantable venous port placement closure. MATERIALS AND METHODS: Seven hundred and ninety-two single-lumen implantable venous port insertions for chemotherapy were reviewed from September 2019 to March 2021 in a retrospective single-centre study. Propensity-score matching by a 1:1 nearest neighbour algorithm was conducted to control for confounding baseline differences. Distances were determined by logistic regression. Propensity-score matching was performed based on the following variables: age at procedure, gender, race, operator's seniority, use of anchoring polypropylene suture (PROLENE), port model, and volume of intra-operative local analgesia. The primary outcome was wound dehiscence at the first follow-up (â¼1 week). RESULTS: The 792 port insertions were conducted in 302 males (38.1%), median age 63 years (IQR: 54-69). Of the 656 wounds closed with subcuticular sutures and skin adhesive, 136 were matched in a 1:1 fashion against procedures closed without a subcuticular suture. No significant differences were demonstrated in pain scores, bleeding, swelling, bruising, fever, wound dehiscence, and discharge at postoperative day 1 (POD1) and at first follow-up between the groups (all p>0.05). Of note, no significant differences in wound dehiscence at first follow-up was found in both unmatched (p=0.133) and matched cohorts (McNemar-Bowker's χ2 = 1.167, p=0.761). CONCLUSION: These findings suggest that the omission of subcuticular sutures during implantable venous port closure may not compromise peri-operative outcomes when OCA skin adhesives were used.
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Neoplasias , Adesivos Teciduais , Adesivos , Cianoacrilatos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Complicações Pós-Operatórias , Estudos Prospectivos , Estudos Retrospectivos , Suturas , Adesivos Teciduais/uso terapêutico , CicatrizaçãoRESUMO
AIM: To examine the relationship between catheter tip location and catheter dysfunction in the context of tunnelled central venous catheters (CVCs) for haemodialysis. MATERIALS AND METHODS: This was a retrospective study of 993 haemodialysis patients who underwent insertion of tunnelled CVCs of step-tip design via the right internal jugular vein (IJV). Based on intra-procedural radiographs, the catheter tip was characterised as being in the superior vena cava (SVC), cavo-atrial junction (CAJ), or deep right atrium (DRA). Patients were tracked for 90 days post-procedure for complications resulting in catheter replacement, and these were compared between cohorts. Statistical analysis was performed with Pearson's chi-square and Fisher's exact tests for categorical variables and two-sample t-test and one-way analysis of variance (ANOVA) for continuous variables. RESULTS: Ninety-five patients (9.6%) experienced catheter dysfunction necessitating replacement within 90 days of insertion. Tip location in SVC was associated with lower occurrence of catheter dysfunction (1.9%) as compared with the CAJ (8%) and DRA (11%; p=0.049). Catheter replacement due to other complications (catheter-associated bacteraemia, cuff dislodgement, exit-site infection, external catheter damage) showed no statistically significant relation to location of the CVC tip. CONCLUSION: When utilising tunnelled CVCs with a step-tip design inserted via the right IJV, location of the catheter tip in the SVC is associated with reduced occurrence of catheter dysfunction as compared to either the CAJ or DRA.
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Cateterismo Venoso Central , Cateteres Venosos Centrais , Cateterismo Venoso Central/efeitos adversos , Cateterismo Venoso Central/métodos , Humanos , Veias Jugulares/diagnóstico por imagem , Diálise Renal , Estudos Retrospectivos , Veia Cava Superior/diagnóstico por imagemRESUMO
AIM: To evaluate the ultra-lose dose imaging protocol (ULDP), compared to the standard low-dose imaging protocol (LDP), which are used for haemodialysis access, in terms of radiation exposure and image quality. MATERIAL AND METHODS: This was a single-centre, institutional review board-approved, prospective, double-blinded randomised controlled study to compare radiation exposure and image quality of the ULDP and LDP. Ten proceduralists, two radiographers, and 11 nurses were enrolled. Radiation exposure during 80 procedures (40 angioplasties and 40 thrombolysis) was recorded (direct radiation to patients from protocol report and scattered radiation to participants from the RaySafe i2 real-time dosimetry system). Baseline characteristics of procedure were recorded. Image quality was assessed subjectively using questionnaires based on the five-point Likert scale after each procedure. RESULTS: Compared with LDP, the use of ULDP was associated with a significantly lower rate of radiation exposure to proceduralists, patients, and scrub nurses (0.506±0.430 versus 0.847±0.965 µSv/s, p=0.044; 0.571±1.284 versus 1.284±1.007 mGy/s, p<0.001; and 0.052±0.071 versus 0.141±0.185 µSv/s, p=0.005, respectively). No significant difference in image quality or duration of procedure was observed (all p values >0.05). CONCLUSION: Compared with LDP, the use of ULDP was associated with a significantly lower rate of radiation exposure to proceduralists, patients, and scrub nurses without compromising the image quality or duration of procedure.
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Angiografia Digital/métodos , Angioplastia/métodos , Oclusão de Enxerto Vascular/cirurgia , Trombólise Mecânica/métodos , Doses de Radiação , Exposição à Radiação/estatística & dados numéricos , Adulto , Protocolos Clínicos , Método Duplo-Cego , Feminino , Fluoroscopia , Humanos , Masculino , Estudos ProspectivosRESUMO
AIM: To evaluate the safety and efficacy of modified wire loop technique for retrograde stent exchange. MATERIALS AND METHODS: All patients were from the KK Women and Children's Hospital where there is no on-site urology service. Patients were identified retrospectively from the institutional radiological information system (RIS) database. In total, 270 stents were removed and 238 replaced for 79 patients between January 2012 to December 2016. Success rates for stent removal and exchange as well as skin dose and fluoroscopy time were assessed. RESULTS: Stent exchange was successful in 234/238 (98%) of cases. Failure was due to loss of access (one case), inability to snare stent due to distorted anatomy (two cases), and extensive encrustation of stent (one case). In 252/270 (93%) cases, stent was removed using modified snare while in 18 (7%) cases, other snare devices were used. Average fluoroscopy time per stent for stent exchange was 573 seconds and average skin dose was 12,494 DAP/mGyâ¢cm2. CONCLUSION: Fluoroscopy-guided retrograde ureteric stent exchange using the modified snare loop technique is effective, quick, and can be performed easily with equipment used in daily intervention practice. It may also be coupled with ureteroplasty, which may help the patient achieve eventual stent-free status.
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Remoção de Dispositivo/métodos , Radiografia Intervencionista , Stents , Obstrução Ureteral/diagnóstico por imagem , Obstrução Ureteral/cirurgia , Adulto , Idoso , Feminino , Fluoroscopia , Humanos , Pessoa de Meia-Idade , Doses de Radiação , Estudos Retrospectivos , Pele/efeitos da radiaçãoRESUMO
Transarterial radioembolisation (TARE) has gained increasing acceptance as an additional/alternative locoregional treatment option for hepatocellular carcinoma, and colorectal hepatic metastases that present beyond potentially curative options. This is a catheter-based transarterial selective internal brachytherapy that involves injection of radioactive microspheres (usually Y-90) that are delivered selectively to the liver tumours. Owing to the combined radioactive and microembolic effect, the findings at follow-up imaging are significantly different from that seen with other transarterial treatment options. Considering increasing confidence among clinicians, refinement in techniques and increasing number of ongoing trials, TARE is expected to gain further acceptance and become an important tool in the armamentarium for the treatment of liver malignancies. So it is imperative that all radiologists involved in the management of liver malignancies are well versed with TARE to facilitate appropriate discussion at multidisciplinary meetings to direct further management. In this article, we provide a comprehensive review on various aspects of radioembolisation with Y-90 for hepatocellular carcinoma including the patient selection, treatment planning, radiation dosimetry and treatment, side effects, follow-up imaging and future direction.
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Embolização Terapêutica/métodos , Radioisótopos de Ítrio/uso terapêutico , Carcinoma Hepatocelular , Humanos , Neoplasias Hepáticas , MicroesferasRESUMO
Using single-walled carbon nanotubes (SWCNTs) as nanomasks on an undoped GaN template, a significant biaxial stress relaxation was achieved in the subsequently-grown Si-doped n-GaN layer. Enhanced near band edge (NBE) emission intensity, similar free carrier concentrations, and the reduced peak width of the asymmetric (102) crystallographic plane all confirmed the suppression of threading dislocations due to the nanoepitaxial growth process. Temperature-dependent photoluminescence (PL) revealed improved internal quantum efficiency (IQE) of InGaN/GaN multi-quantum wells (MQWs) grown on this n-GaN layer. Furthermore, enhanced light output power and a remarkable reduction in efficiency droop were observed for the blue light-emitting diodes (LEDs), especially at higher injection currents. Our results emphasize the strong potential for SWCNTs as nanomasks in the heteroepitaxy of GaN-based devices without the exploitation of complicated lithography or etching processes.
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AIM: To prospectively compare the performance of extracellular space contrast agents (ECSCAs) versus a blood-pool contrast agent (BPCA) for a comprehensive lower-limb magnetic resonance angiography (MRA) protocol in patients with either claudication or critical ischaemia. MATERIALS AND METHODS: Thirty patients with claudication underwent lower-limb magnetic resonance angiography (MRA) (dynamic crural, three-station bolus chase, and infra-inguinal high resolution) using a triphasic injection method with both a ECSCA and BPCA to allow intra-individual comparison, and 30 patients with critical ischaemia were scanned with either a ECSCA or BPCA. The dynamic, bolus chase, and high-resolution images were scored for quality on a Likert scale (from 1-5). Signal- and contrast-to-noise ratios were analysed and statistical analysis performed. RESULTS: Overall, there was no statistically significant difference between the ECSCAs and BPCA for arteriographic dynamic imaging, bolus chase MRA, or the high spatial resolution imaging. Venous image quality was rated higher quality for BPCA scans than for ECSCA images for calf veins (not significantly for thigh veins). Venous imaging signal intensity measures were higher for BPCA imaging. CONCLUSION: Extended-phase imaging using an ECSCA with this protocol provides arteriographic image quality equal to imaging with a BPCA. Venous depiction is good using ECSCAs with this approach, although better with BPCA.
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Meios de Contraste , Aumento da Imagem/métodos , Claudicação Intermitente/diagnóstico por imagem , Isquemia/diagnóstico por imagem , Extremidade Inferior/irrigação sanguínea , Angiografia por Ressonância Magnética/métodos , Idoso , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Extremidade Inferior/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos TestesRESUMO
BACKGROUND: In laparoscopic surgery, no external feedback on the magnitude of the force exerted is available. Hence, surgeons and residents tend to exert excessive force, which leads to tissue trauma. Ability of surgeons and residents to perceive their own force output without external feedback is a critical factor in laparoscopic force-skills training. Additionally, existing methods of laparoscopic training do not effectively train residents and novices on force-skills. Hence, there is growing need for the development of force-based training curriculum. OBJECTIVE: As a first step towards force-based laparoscopic skills training, this study analysed force perception difference between laparoscopic instrument and finger in contralateral bimanual passive probing task. METHODS: The study compared the isometric force matching performance of novices, residents and surgeons with finger and laparoscopic instrument. Contralateral force matching paradigm was employed to analyse the force perception capability in terms of relative (accuracy), and constant errors in force matching. RESULTS: Force perception of experts was found to be better than novices and residents. Interestingly, laparoscopic instrument was more accurate in discriminating the forces than finger. The dominant hand attempted to match the forces accurately, whereas non-dominant hand (NH) overestimated the forces. Further, the NH of experts was found to be most accurate. Furthermore, excessive forces were applied at lower force levels and at very high force levels. CONCLUSIONS: Due to misperception of force, novices and residents applied excessive forces. However, experts had good control over force with both dominant and NHs. These findings suggest that force-based training curricula should not only have proprioception tasks, but should also include bimanual force-skills training exercises in order to improve force perception ability and hand skills of novices and residents. The results can be used as a performance metric in both box and virtual reality based force-skills training.
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Competência Clínica , Simulação por Computador , Currículo , Educação Médica/métodos , Dedos/fisiologia , Laparoscopia/educação , Percepção , HumanosRESUMO
In this Letter, a light-emitting diode (LED) with prism-shaped-air-ring microstructures (PSAMs) formed on flat sapphire substrate is demonstrated as an alternative design to face-up LEDs on patterned sapphire substrate (PSS) for enhanced light extraction efficiency. In this LED design, the emitted photons can be deflected to the top of the chip for its effective extraction, contrary to the PSS-LED wherein photons are guided to sapphire and get absorbed by packaging materials. The PSAM-LED showed an enhancement in the radiometric power as high as 10% with a low far-field angle of 129° over that of a PSS-LED under an injection current of 20 mA.
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AIM: To compare extended-phase imaging using an extracellular space contrast agent, gadobenate dimeglumine, to imaging with a blood-pool contrast agent, gadofosveset, for magnetic resonance angiography. MATERIALS AND METHODS: A lower-limb magnetic resonance angiography (MRA) protocol (dynamic crural, three-station bolus chase, and infra-inguinal high resolution) designed for blood-pool agent imaging was adapted for use with the extracellular agent, gadobenate dimeglumine, primarily by using a triphasic injection protocol. Ten patients scanned with gadofosveset were compared to 10 patients scanned with gadobenate. The dynamic, bolus chase, and high-resolution images were scored for quality on a Likert scale (from 1-5). Signal- and contrast-to-noise ratios were analysed, and Mann-Whitney U statistical analysis performed. RESULTS: There was no significant difference for the dynamic imaging or the aorto-iliac station of the bolus chase. Infra-inguinal bolus chase images were higher quality (p < 0.05 Mann-Whitney U test) with gadobenate. Signal analysis confirmed lower signal and contrast for venous imaging on the high spatial resolution acquisitions with gadobenate; however, this allowed improved arterial conspicuity. CONCLUSION: Extended-phase imaging using an extracellular space contrast agent is feasible and provides image quality to equal imaging with a blood-pool contrast agent.
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Meios de Contraste , Gadolínio , Extremidade Inferior/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Meglumina/análogos & derivados , Compostos Organometálicos , Intensificação de Imagem Radiográfica , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Canal Inguinal/diagnóstico por imagem , Extremidade Inferior/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Projetos Piloto , Sensibilidade e Especificidade , Estatísticas não ParamétricasRESUMO
AIM: To evaluate the current practice of endovascular abdominal aortic aneurysm repair (EVAR) surveillance amongst British Society of Interventional Radiologists (BSIR) members. MATERIALS AND METHODS: A web-based survey (Surveymonkey.com) of BSIR members was performed from June 2011 to September 2011. Questions included who was responsible for organizing follow-up, techniques used in follow-up, and timing of follow-up imaging. RESULTS: The majority (46%) of follow-up is organized by radiologists. In the first year, 74% of imaging interactions involves the use of computed tomography (CT), with 40% of respondents using multiple phases. After the first year, ultrasound is utilized more frequently, usually with plain films. Most patients receive imaging at 1, 6, and 12 months, and thereafter most respondents plan on indefinite yearly follow-up. CONCLUSION: EVAR follow-up protocols in the past have been empirical rather than evidence based. The present survey shows the current range of protocols used in the UK. Despite the frequent use of CT in the first year post-EVAR, there does appear to be a trend towards using ultrasound after the first year of follow-up.
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Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Endovasculares/métodos , Cuidados Pós-Operatórios/métodos , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Protocolos Clínicos , Coleta de Dados , Humanos , Internet , Fatores de Tempo , Tomografia Computadorizada por Raios X , UltrassonografiaRESUMO
The effect of triangular air prism (TAP) arrays with different distance-to-width (d/w) ratios on the enhancement of light extraction efficiency (LEE) of InGaN light-emitting diodes (LEDs) is investigated. The TAP arrays embedded at the sapphire/GaN interface act as light reflectors and refractors, and thereby improve the light output power due to the redirection of light into escape cones on both the front and back sides of the LED. Enhancement in radiometric power as high as 117% and far-field angle as low as 129° are realized with a compact arrangement of TAP arrays compared with that of a conventional LED made without TAP arrays under an injection current of 20 mA.
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Substrate-induced biaxial compressive stress and threading dislocations (TDs) have been recognized to severely impair the performance, stability, and reliability of InGaN/GaN light-emitting diodes (LEDs) for quite some time. In this study, a defect-selective-etched (DSE) porous GaN layer is fabricated employing electro-chemical etching and applied as a buffer layer for the development of InGaN/GaN LEDs with high quantum efficiency. Based on the analysis of photoluminescence and micro-Raman spectra, it has been revealed that the overgrown GaN epilayer on the DSE porous GaN has a relatively low TDs and relaxation of compressive stress in comparison to the conventional GaN epilayer. The remarkable improvement in the internal quantum efficiency of the InGaN/GaN LEDs is directly attributable to the strong radiative recombination in InGaN/GaN multi-quantum-wells caused by stress relaxation and TDs annihilation. Our findings indicate that the use of DSE porous GaN as a buffer layer may be a viable approach for producing crystalline GaN epilayers and high-performance LEDs.
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Vulture declines in South Asia were caused by accidental poisoning by the veterinary non-steroidal anti-inflammatory drug (NSAID) diclofenac. Although veterinary use of diclofenac has been banned, other vulture-toxic NSAIDs are legally available, including aceclofenac, which has been shown to metabolise into diclofenac in domestic cattle. We gave nine domestic water buffalo the recommended dose of aceclofenac (2 mg kg-1 body weight), collected blood at intervals up to 48 h, and carried out a pharmacokinetic analysis of aceclofenac and its metabolite diclofenac in plasma. Aceclofenac was rapidly converted to diclofenac, and was barely detectable in plasma at any sampling time. Diclofenac was present within 20 min, and peaked 4-8 h after dosing. Aceclofenac is a prodrug of diclofenac, and behaves similarly in domestic water buffalo as it did in domestic cattle, posing the same risk to vultures. We recommend an immediate ban on the veterinary use of aceclofenac across vulture-range countries.
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Diclofenaco , Falconiformes , Animais , Bovinos , Diclofenaco/toxicidade , Búfalos/metabolismo , Falconiformes/metabolismo , Anti-Inflamatórios não Esteroides , ÁsiaRESUMO
Population declines of Gyps vultures across the Indian subcontinent were caused by unintentional poisoning by the non-steroidal anti-inflammatory drug (NSAID) diclofenac. Subsequently, a number of other NSAIDs have been identified as toxic to vultures, while one, meloxicam, is safe at concentrations likely to be encountered by vultures in the wild. Other vulture-safe drugs need to be identified to reduce the use of those toxic to vultures. We report on safety-testing experiments on the NSAID tolfenamic acid on captive vultures of three Gyps species, all of which are susceptible to diclofenac poisoning. Firstly, we estimated the maximum level of exposure (MLE) of wild vultures and gave this dose to 40 Near Threatened Himalayan Griffons G. himalayensis by oral gavage, with 15 control birds dosed with benzyl alcohol (the carrier solution for tolfenamic acid). Two birds given tolfenamic acid died with elevated uric acid levels and severe visceral gout, while the remainder showed no adverse clinical or biochemical signs. Secondly, four G. himalayensis were fed tissues from water buffaloes which had been treated with double the recommended veterinary dose of tolfenamic acid prior to death and compared to two birds fed uncontaminated tissue; none suffered any clinical effects. Finally, two captive Critically Endangered vultures, one G. bengalensis and one G. indicus, were given the MLE dose by gavage and compared to two control birds; again, none suffered any clinical effects. The death of two G. himalayensis may have been an anomaly due to i) the high dose level used and ii) the high ambient temperatures at the time of the experiment. Tolfenamic acid is likely to be safe to Gyps vultures at concentrations encountered by wild birds and could therefore be promoted as a safe alternative to toxic NSAIDs. It is manufactured in the region, and is increasingly being used to treat livestock.
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Anti-Inflamatórios não Esteroides , Falconiformes , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Bovinos , Diclofenaco , ortoaminobenzoatos/toxicidadeRESUMO
We demonstrate enhanced light emission in blue light-emitting diodes (LEDs) by multiple Mie scattering from embedded silica nanosphere stacking layers (SNSL). A honeycomb cone structure is introduced in the GaN epilayer to confine a maximum number of silica nanospheres (SNs). We found that the light is predominantly directed vertically by scattering and geometrical effect in SNSL embedded LEDs. Consequently, the light output power is enhanced by 2.7 times, which we attribute to the improvement in light extraction efficiency due to the multiple Mie scattering of light from the embedded SNSL. The experimental results are verified by simulation using finite difference time domain method (FDTD).
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This Letter reports on the fabrication of hybrid white-light-emitting diodes made of semiconductor nanocrystals (NCs) integrated on InGaN/GaN LEDs. Using core type and core/shell type CdSe NCs, the white light properties are systematically engineered for white light generation with high color rendering index (CRI). Unlike CdSe/ZnS core/shell NCs, which exhibited a unique narrowband edge emission, core type CdSe NCs offered extended broad emission toward orange/red wavelengths associated with deep trap states. Consequently, the light-emitting properties of the devices showed strong dependence on the type of NCs used, and devices with CdSe NCs offered admirable characteristics, such as Commission Internationale d'Eclairage coordinates of (0.356, 0.330) and a CRI as high as 87.4.
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Clerodendron inerme, a common hedge plant grown in India, is affected by a yellow mosaic disease caused by a begomovirus. In the present study, the complete genome (DNA A) of this virus was cloned and sequenced. The total size of DNA A is 2760 nucleotides. The genome of this virus contains six open reading frames and a non-coding intergenic region of 293 nucleotides. Nucleotide sequence comparison analysis revealed maximum sequence identity with Papaya leaf curl virus-Pakistan [Pakistan:Cotton:2002] (73.9%). As this virus had less than 89% identity with other begomoviruses, it was identified as a new begomovirus species and tentatively, named as Clerodendron yellow mosaic virus-[India:New Delhi:2007] (ClYMV-[IN:ND:07]).