Laboratory gas-phase infrared spectra of two astronomically relevant PAH cations: diindenoperylene, C32_{32}H16_{16}+^+ and dicoronylene, C48_{48}H20_{20}+^+

The first gas-phase infrared spectra of two isolated astronomically relevant and large PAH cations - diindenoperylene (DIP) and dicoronylene (DC) - in the 530$-$1800 cm$^{-1}$ (18.9$-$5.6 $\mu$m) range - are presented. Vibrational band positions are determined for comparison to the aromatic infrared bands (AIBs). The spectra are obtained via infrared multiphoton dissociation (IRMPD) spectroscopy of ions stored in a quadrupole ion trap (QIT) using the intense and tunable radiation of the free electron laser for infrared experiments (FELIX). DIP$^{+}$ shows its main absorption peaks at 737 (13.57), 800 (12.50), 1001 (9.99), 1070 (9.35), 1115 (8.97), 1152 (8.68), 1278 (7.83), 1420 (7.04) and 1550 (6.45) cm$^{-1}$($\mu$m), in good agreement with DFT calculations that are uniformly scaled to take anharmonicities into account. DC$^+$ has its main absorption peaks at 853 (11.72), 876 (11.42), 1032 (9.69), 1168 (8.56), 1300 (7.69), 1427 (7.01) and 1566 (6.39) cm$^{-1}$($\mu$m), that also agree well with the scaled DFT results presented here. The DIP$^+$ and DC$^+$ spectra are compared with the prominent infrared features observed towards NGC 7023. This results both in matches and clear deviations. Moreover, in the 11.0$-$14.0 $\mu$m region, specific bands can be linked to CH out-of-plane (oop) bending modes of different CH edge structures in large PAHs. The molecular origin of these findings and their astronomical relevance are discussed

Total Synthesis of Aspidosperma and Strychnos Alkaloids through Indole Dearomatization

Monoterpenoid indole alkaloids are the major class of tryptamine-derived alkaloids found in nature. Together with their structural complexity, this has attracted great interest from synthetic organic chemists. In this Review, the syntheses of Aspidosperma and Strychnos alkaloids through dearomatization of indoles are discussed

Sebaran Sukun Dan Persepsi Masyarakat Terhadap Sukun (Artocarpus Communis Forst) Pada Daerah Tangkapan Air Danau Toba Di Nagori Purba Saribu Kecamatan Haranggaol Horison Kabupaten Simalungun

Forests and land in the catchment area of Lake Toba, showed a decrease for quality and quantity of the land. This study aims to determinethe public perception of breadfruit (Artocarpus communis Forst). Research carried out in the catchment area of Lake Toba, Simalungun. Analysing public perception using a questionnaire. Data from the questionnaire were analyzed by descriptive quantitative. Perceptionis influencedby factors of age, education, livelihood and long lived. Research shows that there is a breadfruit distribution point in Haranggaol. Public perception of the breadfruit (Artocarpus communis Forst) is good. Where 58.41% of the people know and understand the benefits of breadfruit

In Situ Cyclization of Proteins (INCYPRO):Cross-Link Derivatization Modulates Protein Stability

Protein macrocyclization represents a very efficient strategy to increase the stability of protein tertiary structures. Here, we describe a panel of novel C3-symmetric tris-electrophilic agents and their use for the cyclization of proteins. These electrophiles are reacted with a protein domain harboring three solvent-exposed cysteine residues, resulting in the in situ cyclization of the protein (INCYPRO). We observe a clear dependency of cross-linking rates on the electrophilicity. All nine obtained cross-linked protein versions show considerably increased thermal stability (up to 29 °C increased melting temperature) when compared to that of the linear precursor. Most interestingly, the degree of stabilization correlates with the hydrophilicity of the cross-link. These results will support the development of novel cross-linked proteins and enable a more rational design process

Low-power amplifier chopper stabilization for a digital-to-analog converter

Includes bibliographical references (p. 59).Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Modern portable media devices demand low-power and low-noise performance from the internal digital-to-analog converter. CMOS design has allowed for oversampling sigma-delta modulation to achieve these goals. However, noise is typically limited by the kT/C noise in the switched capacitor filter following the digital modulation. These filters also require a large amount of on-chip capacitance. The goal of this project is to design a continuous-time output stage for a DAC. A continuous-time output requires much less capacitance than the SC filter. Chopper stabilization is applied to the amplifier to reduce the low-frequency noise. The challenge of this architecture is maintaining amplifier harmonic performance and transient performance. In simulations, chopper stabilization improved signal-to-noise ratio by 11dB while maintaining system level harmonic distortion performance.by Keith Jordy.M.Eng

Penerapan Finiste State Automata Pada Desain Vending Machine Tiket Pakan Hewan Kebun Binatang

A Zoo is a green open space that used to maintain welfare and exhibit animals for the public. Visitors who come to the zoo reach thousands of people a day and some of them are families who want to have recreation. The enthusiasm of visitors can be seen from visitors who want to give food to animals even though it is prohibited because it is dangerous and the animals have a predetermined diet. This study aims to make a vending machine in the form of purchasing tickets for feeding animals at the zoo with the working principle of a vending machine that implements finite state automata. The method used in this study consists of five stages, the first stage is problem identification, the second stage is system design using UML, the third stage is FSA design using state diagrams, the fourth stage is FSA testing using JFLAP, and the last stage is design of vending machine. The conclusion obtained from this study is that the application of the FSA concept to the pet food ticket vending machine can make transactions as many as 6 animal feeding schedules, this can be useful in adding services to the zoo.Kebun binatang merupakan tempat terbuka hijau yang digunakan untuk memelihara kesejahteraan dan memperagakan para satwa untuk umum. Pengunjung yang datang ke kebun binatang mencapai ribuan orang dalam sehari dan diantara nya merupakan keluarga yg ingin berekreasi. Antusiasme pengunjung dapat terlihat dari pengunjung yang ingin memberikan makanan kepada satwa padahal hal itu dilarang karena berbahaya dan para satwa memiliki pola diet makan yang sudah ditentukan. Penelitian ini bertujuan untuk membuat vending machine berupa pembelian tiket pemberian makan satwa di kebun binatang dengan prinsip kerja vending machine yang mengimplementasikan finite state automata dengan menggunakan dua cara pembayaran yaitu uang tunai dan uang digital. Metode yang digunakan dalam penelitian ini terdiri dari lima tahap yaitu tahap pertama identifikasi masalah, tahap kedua perancangan sistem menggunakan UML, tahap ketiga perancangan FSA menggunakan state diagram, tahap keempat pengujian FSA menggunakan JFLAP dan tahap terakhir proses perancangan desain vending machine yang dibuat dengan tampilan yang mudah digunakan. Kesimpulan yang didapat dari penelitian ini adalah penerapan konsep FSA pada vending machine tiket makanan satwa dapat melakukan transaksi sebanyak 6 jadwal makan hewan hal ini dapat bermanfaat dalam menambah pelayanan pada kebun binatang

Internal Jugular Vein Geometry Under Multiple Inclination Angles with 3D Low-Field MRI in Healthy Volunteers

BACKGROUND: Cerebral venous pathways are subjected to geometrical and patency changes due to body position. The internal jugular veins (IJVs) are the main venous drainage pathway in supine position. Their patency and geometry should be evaluated under different body inclination angles over a three‐dimensional (3D) volume in the healthy situation to better understand pathological cases. PURPOSE: To investigate whether positional changes in the body can affect the geometrical properties and patency of the venous system. STUDY TYPE: Prospective. POPULATION: 15 healthy volunteers, of which seven males and median age 22 years in a range of 19–59. FIELD STRENGTH/SEQUENCE: A 0.25‐T tiltable MRI system was used to scan volunteers in 90° (sitting position), 69°, 45°, 21°, and 0° (supine position) in the transverse plane with the top at vertebra C2. A gradient echo sequence was used. ASSESSMENT: Three observers assessed IJVs on patency and created automatic centerlines from which diameter and patency were analysed perpendicular to the vessel at every 4 mm starting at the level of C2. STATISTICAL TESTS: A Student's t test was used to find statistical difference (p < 0.05) in average IJV diameters per inclination angle. RESULTS: The amount of fully collapsed IJVs increased from 33% to 93% (left IJV) and 14% to 80% (right IJV) when increasing the inclination angle from 0° to 90°. In both IJVs, the mean diameter (±SD) of the open vessels was significantly higher at 0° than 90° with 6.3 ± 0.5 mm vs. 4.4 ± 0.1 mm (left IJV) and 6.6 ± 0.6 mm vs. 4.3 ± 0.4 mm (right IJV). DATA CONCLUSION: Tiltable low‐field MRI can be used to assess IJV geometry and its associated venous pathways in 3D under multiple inclination angles. Next to a higher amount of collapsed vessels, the average diameter of noncollapsed vessels decreases with increasing inclination angles for both left and right IJVs. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE:

Bone metastasis in a case of primary acquired melanosis with atypia resulting from conjunctiva melanoma

A 66-year-old woman presented to a tertiary referral centre with a diagnosis of limbal stem cell deficiency secondary to multiple treatments for primary acquired melanosis (PAM) by her referring ophthalmologists. She was known with primary acquired melanosis with severe atypia of the right eye which had been treated with several excisions, cryotherapy and topical chemotherapy. She had PAM over 360° of alternating intensity. Throughout the follow-up period, she developed a cataract and subsequent a retinal detachment for which she underwent a phacovitrectomy on the right eye. There was no nodule present nor did the routine lymph nodes inspection show any enlargement. No abnormalities were observed on intranasal examination. Seven years after the last excision, a metastasis to the spine (Th3) was diagnosed. A complete systemic work-up and a pathological examination did not show any alternative primary melanoma in the body. The original histological material was reviewed again by an ophthalmopathologist. After a new round of stains and immunohistochemistry, the presence of atypical melanocytes in both the epithelium and stroma were found in a scar region leading to a renewed conclusion that the PAM in question was actually the primary melanoma