Luttinger liquid behavior in weakly disordered quantum wires

We have measured the temperature dependence of the conductance in long V-groove quantum wires (QWRs) fabricated in GaAs/AlGaAs heterostructures. Our data is consistent with recent theories developed within the framework of the Luttinger liquid model, in the limit of weakly disordered wires. We show that for the relatively small amount of disorder in our QWRs, the value of the interaction parameter g is g=0.66, which is the expected value for GaAs. However, samples with a higher level of disorder show conductance with stronger temperature dependence, which does not allow their treatment in the framework of perturbation theory. Trying to fit such data with perturbation-theory models leads inevitably to wrong (lower) values of g.Comment: 4 pages, 4 figure

Unusual nanostructures of "lattice matched" InP on AlInAs

We show that the morphology of the initial monolayers of InP on Al0.48In0.52As grown by metalorganic vapor-phase epitaxy does not follow the expected layer-by-layer growth mode of lattice-matched systems, but instead develops a number of low-dimensional structures, e.g., quantum dots and wires. We discuss how the macroscopically strain-free heteroepitaxy might be strongly affected by local phase separation/alloying-induced strain and that the preferred aggregation of adatom species on the substrate surface and reduced wettability of InP on AlInAs surfaces might be the cause of the unusual (step) organization and morpholog

ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI PRODUKSI IKAN BANDENG DI KOTA BANDA ACEH

ABSTRAKPenelitian ini bertujuan untuk mengetahui faktor-faktor yang mempengaruhi produksi ikan bandeng di Kota Banda Aceh. Penelitian ini dilakukan menggunakan metode survey dan pengambilan sampelnya dengan teknik sampel acak sederhana Simple Random Sampling.Lokasi penelitian dilakukan di Kota Banda Aceh, yaitu Kecamatan Syiah Kuala, Meuraxa, Kuta Alam, dan Kuta Raja. Waktu Penelitian dilaksanakan pada bulan Oktober 2013 sampai dengan Juli 2014. Model yang digunakan dalam penelitian ini adalah menggunakan model analisis kuantitatif untuk mengetahui Faktor-faktor yang mempengaruhi produksi ikan bandeng di Kota Banda Aceh yaitu tenaga kerja, luas tambak, jumlah nener, dan penggunaan pupuk..Untuk menguji hubungan antara variabel faktor-faktor yang mempengaruhi produksi ikan bandeng di Kota Banda Aceh, digunakan uji statistik dengan menggunakan uji T, F, dan R2.Hasil penelitian ini dapat disimpulkan bahwa secara serempak faktor , tenaga kerja, luas tambak, jumlah nener, dan jumlah pupuk berpengaruh nyata terhadap produksi ikan bandeng di Kota Banda Aceh. Secara parsial faktor jumlah nener berpengaruh nyata terhadap produksi ikan bandeng di Kota Banda Aceh. Sedangkan faktor tenaga kerja, luas tambak dan jumlah pupuk tidak berpengaruh nyata terhadap produksi ikan bandeng di Kota Banda Aceh.Kata Kunci: Ikan bandeng, analisis produksiABSTRACTThis research aims to determine the factors that affect fish production in the city of Banda Aceh. This research was conducted using a survey method and sampling with simple random sampling techniques.Location of the research conducted in the city of Banda Aceh , the District Syiah KuaLa, Meuraxa, Kuta Alam, and Kuta Raja. Time research conducted in October 2013 to July 2014 model used in this research was to use quantitative analysis model to determine the factors that affect milkfish production in Banda Aceh, namely labor, large farms, the amount of milkfish, and use of fertilizers.For Examine the relationship between the variable factors that affect milkfish production in Banda Aceh, used statistical tests using T test, F, and R2.The results of this research it can be concluded that the factors simultaneously, labor, large ponds, milkfish amount, and the amount of fertilizer significantly affect milkfish production in the city of Banda Aceh. Partially factors significantly affect the amount of milkfish fry production of milkfish in Banda Aceh. While the labor factor, vast farms and the amount of fertilizer had no significant effect on the production of milkfish in Banda Aceh .Keywords: Milkfish, production analysisBanda Ace

Enhancement of the Binding Energy of Charged Excitons in Disordered Quantum Wires

Negatively and positively charged excitons are identified in the spatially-resolved photoluminescence spectra of quantum wires. We demonstrate that charged excitons are weakly localized in disordered quantum wires. As a consequence, the enhancement of the "binding energy" of a charged exciton is caused, for a significant part, by the recoil energy transferred to the remaining charged carrier during its radiative recombination. We discover that the Coulomb correlation energy is not the sole origin of the "binding energy", in contrast to charged excitons confined in quantum dots.Comment: 4 Fig

Long-term subjective outcomes of barbed reposition pharyngoplasty for obstructive sleep apnea syndrome treatment

Background: The purpose of this study was to evaluate long-term subjective outcomes of barbed reposition pharyngoplasty for obstructive sleep apnea syndrome (OSAS) treatment using a specific questionnaire, the Palate Postoperative Problem Score (PPOPS). Methods: 140 patients who underwent barbed reposition pharyngoplasty (BRP) surgery in the Morgagni Pierantoni Hospital of Forlì, Italy were enrolled in the study. Postoperative outcomes were evaluated in a short- and long-term follow-up using the PPOPS questionnaire. The average period of follow-up was 26 months. All patients received the PPOPS questionnaire by telephone in a period between April and August 2019. Results: 51% of patients complained of swallowing problems after surgery. In 91% of cases, the problem cleared up spontaneously. At the time of the interview, only 9% of patients had a residual swallowing difficult. At the time of PPOPS evaluation, rhinolalia was observed in 8% of patients, whereas nose regurgitation was present in 2% of patients. In 20% of patients, the foreign body sensation was present during follow-up. The value of apnea-hypopnea index (AHI) reduced from the preoperative value of 31.5 to the postoperative value of 11.4. Conclusions: BRP surgery proved to be an effective technique, appreciated by the majority of patients. Use of the PPOPS questionnaire has demonstrated that the BRP technique seems to ensure efficacy and lower morbidity, with few complications after surgery

Don't forget ototoxicity during the SARS-CoV-2 (Covid-19) pandemic!

Aim of this communication is to remind clinical professionals to be aware of ototoxic side effects of several specific drugs proposed for the treatment of the new virus SARS-CoV-2 (Covid-19). In particular, chloroquine and hydroxychloroquine, azithromycin, as well as antiviral drugs such as remdesivir, favipiravir and lopinavir can all present potential ototoxic side effects. The data in the literature do not offer specific information on their potential synergetic effects nor on their interactions

SARS-CoV-2 (COVID-19) and audio-vestibular disorders

To describe the audio-vestibular disorders related to the newly SARS-CoV-2 infection, including the possible ototoxicity side-effects related to the use of drugs included in the SARS-CoV-2 treatment protocols. A systematic review was performed according to the PRISMA protocol. The Medline and Embase databases were searched from March 1, 2020 to April 9, 2021. Initially the search yielded 400 manuscripts, which were reduced to 15, upon the application of inclusion criteria. Sensorineural hearing loss (SNHL) is the most frequent audio-vestibular symptom described, occurring alone or in association with tinnitus and vertigo. The etiopathogenesis of the inner ear disorders related to COVID-19 infection is still poorly understood. The number of reports of COVID-19 infections associated to audio-vestibular disorders is increasing; even if the quality of the studies available is often insufficient, audio-vestibular disorders should be considered as possible manifestations to be included among the symptoms of this infection

Genetic polymorphisms and sepsis in premature neonates

Identifying single nucleotide polymorphisms (SNPs) in the genes involved in sepsis may help to clarify the pathophysiology of neonatal sepsis. The aim of this study was to evaluate the relationships between sepsis in pre-term neonates and genes potentially involved in the response to invasion by infectious agents. The study involved 101 pre-term neonates born between June 2008 and May 2012 with a diagnosis of microbiologically confirmed sepsis, 98 pre-term neonates with clinical sepsis and 100 randomly selected, otherwise healthy pre-term neonates born during the study period. During the study, 47 SNPs in 18 candidate genes were genotyped on Guthrie cards using an ABI PRISM 7900 HT Fast real-time and MAssARRAY for nucleic acids instruments. Genotypes CT and TT of rs1143643 (the IL1\u3b2 gene) and genotype GG of rs2664349GG (the MMP-16 gene) were associated with a significantly increased overall risk of developing sepsis (p = 0.03, p = 0.05 and p = 0.03), whereas genotypes AG of rs4358188 (the BPI gene) and CT of rs1799946 (the DEF\u3b21 gene) were associated with a significantly reduced risk of developing sepsis (p = 0.05 for both). Among the patients with bacteriologically confirmed sepsis, only genotype GG of rs2664349 (the MMP-16 gene) showed a significant association with an increased risk (p = 0.02). Genotypes GG of rs2569190 (the CD14 gene) and AT of rs4073 (the IL8 gene) were associated with a significantly increased risk of developing severe sepsis (p = 0.05 and p = 0.01). Genotype AG of rs1800629 (the LTA gene) and genotypes CC and CT of rs1341023 (the BPI gene) were associated with a significantly increased risk of developing Gram-negative sepsis (p = 0.04, p = 0.04 and p = 0.03). These results show that genetic variability seems to play a role in sepsis in pre-term neonates by influencing susceptibility to and the severity of the disease, as well as the risk of having disease due to specific pathogens. \ua9 2014 Esposito et al