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OBJECTIVE: Central sleep apnea (CSA) is a rare condition in children; however, it can cause significant morbidity if not diagnosed early. We aimed to increase the knowledge about CSA in children by describing the clinical characteristics of children diagnosed with CSA at our sleep center. MATERIAL AND METHODS: We retrospectively reviewed 1263 polysomnographies (PSG) performed between 2012 and 2023 at our tertiary sleep center and evaluated the clinical characteristics of the patients with CSA. Underlying diseases, clinical symptoms, sleep parameters, and short-term management of the patients were recorded. RESULTS: Of the 1263 patients aged between 1 month and 18 years, 122 (9.65%) had CSA, with 54.9 % (n = 67) of them being female. Only 56.6% (n = 69) of the patients' parents had reported a symptom indicating sleep-disordered breathing. The most common underlying disease was genetic, including Down and Prader-Willi syndromes, followed by neurological diseases. Obstructive sleep apnea was detected in addition to CSA in 103 of the patients (84.4%). Bi-level positive airway pressure with a backup rate was the most common treatment modality. CONCLUSION: While CSA is a rare clinical condition in children, it occurs more commonly in those with an underlying disease. Awareness of the disease and timely referral of the patients for sleep studies are critical to prevent long-term sequelae. [ABSTRACT FROM AUTHOR]

Designing efficient and cost‐effective electrocatalysts in simple ways is very important for energy efficiency. In this sense, nano‐sized materials have been extensively utilized for the development of efficient electrodes for electrochemical CO2 reduction. In the present study, we have developed a Sn/chitosan‐reduced graphene oxide (chi‐rGO)/SnO2 composite electrode via only electrochemical techniques and tested it for electrochemical reduction of CO2 to formate. A bare Sn plate was modified with a reduced graphene oxide layer in the presence of chitosan to get a stable Sn/chi‐rGO composite structure and to get more active sites, thus an efficient reduction process was performed. The surface of the Sn/chi‐rGO composite was further modified by SnO2 nanoparticles via the potentiostatic electrodeposition method at a fixed applied potential of −0.6 V for varying periods. The calculated double‐layer capacitance (Cdl) of the Sn/chi‐rGO/SnO2 electrode was about 80 times larger than the bare Sn plate implying that the coexistence of SnO2 nanoparticles on the (chi‐rGO) structure enhanced the electrochemically active sites. The maximum Faradaic efficiency was recorded as 88 % towards the production of formate at an average current density of −7.36 mAcm−2 at −1.8 V. Electrochemical measurements and the stability test revealed that the resultant Sn/chi‐rGO/SnO2 composite structure behaves as a potential electrode material for efficient CO2 conversion to formate.The study presents a simple and low‐cost electrode preparation procedure including only electrochemical techniques which can be conducted within a very short time and without using extra energy and chemicals/additives. [ABSTRACT FROM AUTHOR]

Because of the hydrophobic nature of the membrane lipid bilayer, the majority of the hydrophilic solutes require special transportation mechanisms for passing through the cell membrane. Integral membrane transport proteins (MTPs), which belong to the Major Intrinsic Protein Family, facilitate the transport of these solutes across cell membranes. MTPs including aquaporins and carrier proteins are transmembrane proteins spanning across the cell membrane. The easy handling of microorganisms enabled the discovery of a remarkable number of transport proteins specific to different substances. It has been realized that these transporters have very important roles in the survival of microorganisms, their pathogenesis, and antimicrobial resistance. Astonishing features related to the solute specificity of these proteins have led to the acceleration of the research on the discovery of their properties and the development of innovative products in which these unique properties are used or imitated. Studies on microbial MTPs range from the discovery and characterization of a novel transporter protein to the mining and screening of them in a large transporter library for particular functions, from simulations and modeling of specific transporters to the preparation of biomimetic synthetic materials for different purposes such as biosensors or filtration membranes. This review presents recent discoveries on microbial membrane transport proteins and focuses especially on formate nitrite transport proteins and aquaporins, and advances in their biotechnological applications. [ABSTRACT FROM AUTHOR]

nirC gene coding for the nitrite channel of E. coli K12 was cloned into the pET28a vector and expressed in E. coli BL21 cells. 28.5 kDa NirC monomer was purified from membrane components of E. coli. Selectivity of NirC for different ions including nitrite, nitrate, sulfate, formate, and acetate anions, and a divalent cation, magnesium, was compared with that of bacterial aquaporin from Halomonas elongata. Water and ion permeability values were determined by measuring the light scattering rates of proteoliposomes containing NirC and aquaporins during their water loss and gain. NirC shows a selective permeability to nitrite and is more resistant to the entry of other anions as compared to aquaporin. The single channel permeability of NirC for nitrite is about 10-fold that of a single aquaporin channel. Both aquaporin and NirC channel proteins were impermeable to MgCl2 and (NH4)2SO4 and their permeability to other tested ions was remarkably lower as compared to nitrite ions. The study also presents the 3D model and channel characteristics of NirC. The translocation channel of E. coli NirC is determined to be larger, and its length is shorter than aquaporin channels. Although the NirC channel throat is more hydrophobic than aquaporin, its water permeability is almost equal to that of aquaporin. The hydrophobic nature of the NirC channel might play an important role in the selective permeability of the channel for nitrite ions. [ABSTRACT FROM AUTHOR]

Nitrogen oxide (NOx) emissions cause significant impacts on the environment and must therefore be controlled even more stringently. This requires the development of cost-effective removal strategies which simultaneously create value-added by-products or energy from the waste. This study aims to treat gaseous nitric oxide (NO) by hollow-fibre membrane biofilm reactor (HFMBfR) in the presence of nitrite ( NO 2 − ) and evaluate nitrous oxide (N2O) emissions formed as an intermediate product during the denitrification process. Accumulated N2O can be utilised in methane oxidation as an oxidant to produce energy. In the first stage of the study, the HFMBfR was operated by feeding only gaseous NO as the nitrogen source. During this period, the best performance was achieved with 92% NO removal efficiency (RE). In the second stage, both NO gas and NO 2 − were supplied to the system, and 91% NO and 99% NO 2 − reduction were achieved simultaneously with the maximum N2O generation of 386 ± 31 ppm. Lower influent carbon to nitrogen (C/N) ratios, such as 4.5 and 2.0, and higher NO 2 − −N loading rate of 158 mg N day−1 favoured N2O generation. An improved NO removal rate and N2O accumulation were seen with the increasing amount of PO 4 3 − in the medium. The 16S rDNA sequencing analysis revealed that Alicycliphilus denitrificans and Pseudomonas putida were the dominant species. The study shows that an HFMBfR can be successfully used to eliminate both NO 2 − and gaseous NO and simultaneously generate N2O by adjusting the system parameters such as C/N ratio, NO 2 − and PO 4 3 − loading. [ABSTRACT FROM AUTHOR]

Aim: This study aims to reveal the problems faced by families of children with spinal muscular atrophy (SMA), by evaluating their care burden, needs, and expectations. Materials and Methods: The participants were the primary caregivers of 34 children between the ages of 0 and 18 years diagnosed with SMA. Thirteen children were diagnosed with type 1, 13 children with type 2 and 8 children with type 3 SMA. Data on the medical history, functional levels of the participants, and the characteristics of families were collected. The childrens' parents completed the Family Needs Survey and the Zarit Caregiver Burden Scale. Results: According to the results of the Family Needs Survey, it was found that information was the most common requirement, and this was independent of the level of education. According to the Caregiver Burden Scale, it was recorded that 64.7% of the caregivers were under mild/ moderate burden. While there was a moderate correlation (r = 0.574; P < .001) between the Caregiver Burden Scale and the Family Needs Survey, it was observed that the functional level of the child was not associated with family needs and caregiver burden. Conclusions: Our study suggests that the needs of families of SMA patients, especially related to income level, have changed. The caregivers' burden is not directly related to the income level or the functional level of the child. Families' need for information should also be prioritized within the rehabilitation program. [ABSTRACT FROM AUTHOR]

Glucose, urea, and glycerol rejection capacities of thin film composite polysulfone membranes prepared with Escherichia coli and Halomonas elongata aquaporins were determined. Water permeability of the membranes was increased without a remarkable decrease in glycerol and urea rejection capacities when H. elongata aquaporin was incorporated into the membrane structure. High water permeability led to high volume processing and high solute rejection per unit time. Eight percent increase in glucose rejection capacity with a 27% increase in water permeability was achieved with E. coli aquaporin incorporated into the membrane structure. Aquaporins from two different bacterial sources displayed different properties in terms of organic solute transportation. [ABSTRACT FROM AUTHOR]

An extensive monitoring study of volatile organic compounds (VOCs) was conducted at sites across the highly industrialized town of Dilovasi, northern Turkey to determine temporal and spatial trends in pollutant concentrations and relate to the effects of source locations, meteorology, and topography. Two-week passive samplers (Tenax tubes) were deployed at twelve sites from February to December 2012 and analysed using thermal desorption and gas chromatography with mass spectrometric detection (TD-GC-MS). Sampled total VOC (TVOC) levels were highest in the July through October period and were highest at low-altitude sites near industry facilities and vehicle traffic sources (148.3 µg/m at site 11, 154.1 µg/m at site 10) and lowest at high-altitude sites located furthest upwind from industry and traffic sources (78.4 µg/m at site 5 and 78.5 µg/m at site 6). Analysis of 'T/B' ratios suggested that contributions to ambient VOC in Dilovasi are dominated by the town's industrial sources. Meteorological conditions and the town's basin topography were also found to significantly influence the city's air quality, with strong winds from the NE observed to correlate with periods of higher sampled TVOC. Compared with other industrialized urban centers, the study revealed that there is significant toluene pollution in Dilovasi and recommended enhanced continuous monitoring at the city's industrial and residential zones. [ABSTRACT FROM AUTHOR]

Nitrogen monoxide (NO) and nitrogen dioxide referred as NOxare one of the most important air pollutants in the atmosphere. Biological NOxremoval technologies have been developing to reach a cost-effective control method for upcoming stringent NOxemission standards. The BioDeNOx system was seen as a promising biological NOxcontrol technology which is composed of two reactors, one for absorbing of NO in an aqueous Fe(II)EDTA2−solution and the other for subsequent reduction to N2gas in a biological reactor by the denitrification process. In this study, instead of two discrete reactors, only one jet-loop bioreactor (JLBR) was utilized as both absorption and denitrification unit and no chelate-forming chemicals were added. In other words, the advantage of better mass transfer conditions of jet bioreactor was used instead of Fe(II)EDTA2−. The process was named as Jet-BioDeNOx. The JLBR was operated for the removal of NOxfrom air streams containing 500–3000 ppm NOxand the results showed that the removal efficiency was between 81% and 94%. The air to liquid flow ratio (QG/QRAS) varied in the range of 0.07–0.12. Mathematical modelling of the system demonstrated that the removal efficiency strongly depends on this ratio. The high mass transfer conditions prevailed in the reactor provided a competitive advantage on removing NO gas without any requirement of chelating chemicals. [ABSTRACT FROM PUBLISHER]

This article introduces a simple, rapid, and reliable solid-phase microextraction ( SPME) method coupled with GC- MS for the quantitative determination of 16 polycyclic aromatic hydrocarbons in water. In this study, the Taguchi experimental design was used to optimize extraction conditions of polycyclic aromatic hydrocarbons using SPME method to obtain highly enriched analytes. Consequently, quantitative determination of polycyclic aromatic hydrocarbons in water was achieved by GC- MS technique. The selected parameters affecting enrichment of polycyclic aromatic hydrocarbons were sample extraction time, stirring speed, temperature, ionic strength, and pH. The study revealed that optimal operating conditions were found to be 90-min extraction time, 1400 rpm stirring speed, and 60°C sample temperature. The effect of ionic strength and pH were shown to be insignificant. Optimized conditions were also reevaluated by placing the 16 polycyclic aromatic hydrocarbons into several subgroups based on their molecular weight. The extraction efficiency of polycyclic aromatic hydrocarbons with low molecular weight was shown to be a function of only the extracting temperature. Satisfactory results were obtained for linearity (0.983-0.999), detection limits (2.67-18.02 ng/L), accuracy (71.2-99.3%), and precision (4.3-13.5%). The optimum conditions reported by other design approaches were evaluated and generalized optimum conditions were suggested. [ABSTRACT FROM AUTHOR]