47 research outputs found

    RANCANG BANGUN ALAT PENGUKUR JARAK AMAN MOBIL PADA AREA TEMPAT PARKIR UMUM MENGGUNAKAN SENSOR ULTRASONIC HC-SR04 DAN ARDUINO UNO

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    Penelitian ini bertujuan untuk mengetahui bagaimana tahapan membuat prototype alat pengukurjarak aman mobil menggunakan sensor ultrasonic HC-SR04 berbasis mikrokontroler arduino uno.Penelitian ini menggunakan metode R&D yaitu metode penelitian yang digunakan untuk menghasilkanproduk tertentu dan menguji keefektifan produk tersebut. Hasil penelitian menunjukan terdapat tiga tahapdalam membuat sistem pengukur jarak aman mobil yaitu tahapan persiapan yang berkaitan denganperancangan yang harus dipersiapkan demi menunjang proses pengerjaan, tahapan pelaksanaan yaitumemulai proses Alat Pengukur Jarak Aman Mobil Pada Area Tempat Parkir Umum Menggunakan SensorUltrasonic HC-SR04 Dan Arduino Uno serta tahap akhir menganalisa keberhasilan dari proses perakitansistem pengukur jarak aman mobil

    Transesterification of sago starch and waste palm cooking oil in densified CO<sub>2</sub>

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    In this work, the synthesis of biodegradable and yet renewable thermoplastics materials through a transesterification reaction of sago starch and waste palm cooking oil (WPO) in densified CO2 as the solvent is reported. The aim of this research is to investigate the potential used of sago starch and WPO as raw materials in the thermoplastics starch synthesis. The starch esters was successfully synthesized using sago starch and WPO as reagent in densified CO2 as shown from the presence of carbonyl group (C=O, 1743 cm-1) in the FT-IR spectra coupled with the presence of the proton (1H-NMR) of the fatty acid in the starch backbone (0.8 - 2 ppm). The product crystallinity decreases as shown in XRD results and resulting with a change in the thermal properties (melting and crystalline temperature) of the products. In addition, the products show a different granular morphology and a higher hydrophobicity compared with native sago starch. This research shows the potential used of sago starch and WPO in the thermoplastics starch synthesis and opens a new perspective on the product application

    Novel trivalent europium ÎČ-diketonate complexes with N-(pyridine-2-yl)amides and N-(pyrimidine-2-yl)amides as ancillary ligands: photophysical properties and theoretical structural modeling

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    Eighteen new Eu3+ complexes and their Gd3+ analogues with 1,3-diketonate as main ligands and N-(pyridine-2-yl)amides or N-(pyrimidine-2-yl)amides as ancillary ligands were synthesized. The replacement of water molecules by those amides in the Eu3+ complexes increase the intrinsic quantum yields of luminescence, making them comparable or even more efficient than Eu3+ complexes with standard ancillary ligands such as 2,2â€Č-bipyridine. The luminescence spectra of Gd3+ complexes in comparison with the Eu3+ ones show that efficient ligand-to-metal intramolecular energy transfer processes take place. In most cases the experimental Judd-Ofelt intensity parameters (Ω2 and Ω4) for the Eu3+ complexes show variations as a function of the temperature (77 and 300 K) that overall apparently does not follow clearly any trend. For this reason, geometric variations (on the azimuthal angle φ and ancillary ligands distances) were carried out in the coordination polyhedron for simulating thermally induced structural changes. It has been observed that, in this way, the Ω2 and Ω4 can be satisfactorily reproduced by in silico experiments. It was concluded that, at low-temperature, the ancillary ligands become closer to the Eu3+ ion and the angular variations affect more Ω2 than Ω4, in agreement to the theoretical calculations. The use of N-(pyridine-2-yl)amides or N-(pyrimidine-2-yl)amides as ancillary ligands in Eu3+ 1,3-diketonates looks to be a good strategy for obtaining highly luminescent complexes.publishe

    Seven-coordinate Tb3+ complexes with 90% quantum yields: High-performance examples of combined singlet- and triplet-to-Tb3+ energy-transfer pathways

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    Seven-coordinate, pentagonal-bipyramidal (PBP) complexes [Ln(bbpen)Cl] and [Ln(bbppn)Cl], in which Ln = Tb3+ (products I and II), Eu3+ (III and IV), and Gd3+ (V and VI), with bbpen2- = N,Nâ€Č-bis(2-oxidobenzyl)-N,Nâ€Č-bis(pyridin-2-ylmethyl)ethylenediamine and bbppn2- = N,Nâ€Č-bis(2-oxidobenzyl)-N,Nâ€Č-bis(pyridin-2-ylmethyl)-1,2-propanediamine, were synthesized and characterized by single-crystal X-ray diffraction analysis, alternating-current magnetic susceptibility measurements, and photoluminescence (steady-state and time-resolved) spectroscopy. Under a static magnetic field of 0.1 T, the Tb3+ complexes I and II revealed single-ion-magnet behavior. Also, upon excitation at 320 nm at 300 K, I and II presented very high absolute emission quantum yields (0.90 ± 0.09 and 0.92 ± 0.09, respectively), while the corresponding Eu3+ complexes III and IV showed no photoluminescence. Detailed theoretical calculations on the intramolecular energy-transfer rates for the Tb3+ products indicated that both singlet and triplet ligand excited states contribute efficiently to the overall emission performance. The expressive quantum yields, QLnL, measured for I and II in the solid state and a dichloromethane solution depend on the excitation wavelength, being higher at 320 nm. Such a dependence was rationalized by computing the intersystem crossing rates (WISC) and singlet fluorescence lifetimes (τS) related to the population dynamics of the S1 and T1 levels. Thin films of product II showed high air stability and photostability upon continuous UV illumination, which allowed their use as downshifting layers in a green light-emitting device (LED). The prototypes presented a luminous efficacy comparable with those found in commercial LED coatings, without requiring encapsulation or dispersion of II in host matrixes. The results indicate that the PBP environment determined by the ethylenediamine (en)-based ligands investigated in this work favors the outstanding optical properties in Tb3+ complexes. This work presents a comprehensive structural, chemical, and spectroscopic characterization of two Tb3+ complexes of mixed-donor, en-based ligands, focusing on their outstanding optical properties. They constitute good molecular examples in which both triplet and singlet excited states provide energy to the Tb3+ ion and lead to high values of QLnL

    Uncommon nucleotide excision repair phenotypes revealed by targeted high-throughput sequencing

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    BACKGROUND: Deficient nucleotide excision repair (NER) activity causes a variety of autosomal recessive diseases including xeroderma pigmentosum (XP) a disorder which pre-disposes to skin cancer, and the severe multisystem condition known as Cockayne syndrome (CS). In view of the clinical overlap between NER-related disorders, as well as the existence of multiple phenotypes and the numerous genes involved, we developed a new diagnostic approach based on the enrichment of 16 NER-related genes by multiplex amplification coupled with next-generation sequencing (NGS). METHODS: Our test cohort consisted of 11 DNA samples, all with known mutations and/or non pathogenic SNPs in two of the tested genes. We then used the same technique to analyse samples from a prospective cohort of 40 patients. Multiplex amplification and sequencing were performed using AmpliSeq protocol on the Ion Torrent PGM (Life Technologies). RESULTS: We identified causative mutations in 17 out of the 40 patients (43 %). Four patients showed biallelic mutations in the ERCC6(CSB) gene, five in the ERCC8(CSA) gene: most of them had classical CS features but some had very mild and incomplete phenotypes. A small cohort of 4 unrelated classic XP patients from the Basque country (Northern Spain) revealed a common splicing mutation in POLH (XP-variant), demonstrating a new founder effect in this population. Interestingly, our results also found ERCC2(XPD), ERCC3(XPB) or ERCC5(XPG) mutations in two cases of UV-sensitive syndrome and in two cases with mixed XP/CS phenotypes. CONCLUSIONS: Our study confirms that NGS is an efficient technique for the analysis of NER-related disorders on a molecular level. It is particularly useful for phenotypes with combined features or unusually mild symptoms. Targeted NGS used in conjunction with DNA repair functional tests and precise clinical evaluation permits rapid and cost-effective diagnosis in patients with NER-defects

    Mechanism of KMT5B haploinsufficiency in neurodevelopment in humans and mice.

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    Pathogenic variants in KMT5B, a lysine methyltransferase, are associated with global developmental delay, macrocephaly, autism, and congenital anomalies (OMIM# 617788). Given the relatively recent discovery of this disorder, it has not been fully characterized. Deep phenotyping of the largest (n = 43) patient cohort to date identified that hypotonia and congenital heart defects are prominent features that were previously not associated with this syndrome. Both missense variants and putative loss-of-function variants resulted in slow growth in patient-derived cell lines. KMT5B homozygous knockout mice were smaller in size than their wild-type littermates but did not have significantly smaller brains, suggesting relative macrocephaly, also noted as a prominent clinical feature. RNA sequencing of patient lymphoblasts and Kmt5b haploinsufficient mouse brains identified differentially expressed pathways associated with nervous system development and function including axon guidance signaling. Overall, we identified additional pathogenic variants and clinical features in KMT5B-related neurodevelopmental disorder and provide insights into the molecular mechanisms of the disorder using multiple model systems

    A neurodegenerative perspective on mitochondrial optic neuropathies

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