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The VLA H I Observations of Stephan\u27s Quintet (HCG 92)*
Using the Very Large Array, we have made spectral-line and continuum observations of the neutral hydrogen in the direction of the compact group of galaxies Stephan\u27s Quintet. The high-velocity clouds between 5600 and 6600 km s-1, the disk of the foreground galaxy NGC 7320 at 800 km s-1, the extended continuum ridge near the center of the group, and three faint dwarflike galaxies in the surrounding field were imaged with the C, CS, and D configurations. Four of the H I clouds previously detected are confirmed. The two largest H I features are coincident with and concentrated mainly along separate large tidal tails that extend eastward. The most diffuse of the four clouds is resolved into two clumps, one coinciding with tidal features south of NGC 7318A and the other devoid of any detectable stellar or Hα sources. The two compact clouds along the same line of sight have peak emission at luminous infrared and bright Hα sources probably indicative of star-forming activity. The total amount of H I detected at high redshifts is ~1010M. As in previous H I studies of the group, no detectable emission was measured at the positions of any high-redshift galaxies, so that any H I still bound to their disks must be less than 2.4 × 107 M
Entanglement dynamics for the double Tavis-Cummings model
A double Tavis-Cummings model (DTCM) is developed to simulate the
entanglement dynamics of realistic quantum information processing where two
entangled atom-pairs and are distributed in such a way that atoms
are embedded in a cavity while are located in another remote
cavity . The evolutions of different types of initially shared entanglement
of atoms are studied under various initial states of cavity fields. The results
obtained in the DTCM are compared with that obtained in the double
Jaynes-Cummings model (DJCM) [J. Phys. B \textbf{40}, S45 (2007)] and an
interaction strength theory is proposed to explain the parameter domain in
which the so-called entanglement sudden death occurs for both the DTCM and
DJCM.Comment: 11 figure
Optimisasi Robust Untuk Masalah Pengendalian Biaya Persediaan Produk Sandal
Persediaan merupakan bagian utama dalam kegiatan perusahaan yang dapat berdampak buruk jika tidak dikelola dengan baik. Pengendalian Persediaan harus direncanakan serta dikendalikan secara efektif dan efisien. Masalah umum dalam pengendalian persediaan biasanya terjadi dikarenakan terdapat parameter yang mengandung ketidakpastian data seperti permintaan produk yang tidak pasti. Optimisasi robust merupakan model optimisasi yang mengandung data ketidakpastian (uncertainty) untuk memperoleh solusi yang tepat dengan menggunakan penyelesaian secara Linear Programming. Model ini diterapkan pada data permintaan produk sandal yang tidak pasti di PT. XYZ. Metode optimisasi Robust ini menghasilkan biaya persediaan total selama 1 tahun sebesar Rp. 3.220.730.093 yang lebih kecil daripada biaya persediaan PT. XYZ yaitu sebesar Rp. 3.660.693.904
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Supply is a main part in the company activities that has a bad impact if not managed properly. Supply control must be planned and controlled effectively and efficiently. Common problems of the supply control usually occurs because there are parameters that contain data uncertainty such as unknown product demand. Robust optimization is a optimization model containing data uncertainty to obtain the right solution using Linear Programming. This model is applied to the uncertain data of slippers products demand PT. XYZ. This Robust optimization method produces total inventory cost of Rp. 3.220.730.093 for a year which is less than the inventory cost of PT. XYZ that is Rp. 3.660.693.90
Mechanism of Crosstalk between the LSD1 Demethylase and HDAC1 Deacetylase in the CoREST Complex.
The transcriptional corepressor complex CoREST is one of seven histone deacetylase complexes that regulate the genome through controlling chromatin acetylation. The CoREST complex is unique in containing both histone demethylase and deacetylase enzymes, LSD1 and HDAC1, held together by the RCOR1 scaffold protein. To date, it has been assumed that the enzymes function independently within the complex. Now, we report the assembly of the ternary complex. Using both structural and functional studies, we show that the activity of the two enzymes is closely coupled and that the complex can exist in at least two distinct states with different kinetics. Electron microscopy of the complex reveals a bi-lobed structure with LSD1 and HDAC1 enzymes at opposite ends of the complex. The structure of CoREST in complex with a nucleosome reveals a mode of chromatin engagement that contrasts with previous models
The status of e-learning, personality traits, and coping styles among medical students during the COVID-19 pandemic: a cross-sectional study
ObjectiveThe objective of this study was to explore the learning preferences and habits of medical students during the pandemic home e-learning, and to investigate the incidence of adverse emotions, optimistic character level and coping style. To explore the influencing factors of adverse emotions.MethodsA cross-sectional survey was conducted in China from March to June 2022. Medical students were recruited from three universities in China, and a questionnaire survey was conducted. The questionnaires consisted of a “e-learning preferences and habits questionnaire”, life orientation test questionnaire (LOT-R), and simple coping style questionnaire (SCSQ). Finally, a total of 492 medical students who met the inclusion and exclusion criteria became the research subjects and completed the survey.ResultsA total of 57.7% believed they experienced no adverse emotions during home e-learning. ① During the COVID-19 pandemic, the score of optimistic personality of medical students was (7.25 ± 1.933), and the score of pessimistic personality was (5.82 ± 2.240). The score of positive coping was (21.75 ± 5.379), and the score of negative coping was (11.75 ± 3.611). ② The occurrence of medical students' adverse emotions during e-learning was influenced by “Whether there is a private, quiet space to study”, “Degree of knowledge mastery”, “Physical discomfort or not”, “Keep a regular schedule or not”, “Optimistic personality tendency”.ConclusionThis study demonstrates the during home e-learning, most medical students have their own learning equipment and can meet their learning needs. Their favorite mobile device to use is a mobile phone, and their favorite method of teaching is to provide course playback. More than half of medical students believe that they have some inconvenience in conducting research during home e-learning. With regard to teacher's real-time screen, the largest number of medical students support teachers turning on live screens so that they feel like they are interacting with the teacher. The preference for blended teaching is highest among medical students. In general, medical students were highly adaptive of the newest e-learning approach. Based on the statistic analysis, the factors that “Whether there is a private, quiet space to study”, “Degree of knowledge mastery”, “Physical discomfort or not”, “Keep a regular schedule or not”, and “Optimistic personality tendency” may be the influencing factors for the occurrence of adverse emotions
Effect of coating with combined chitosan and gallic acid on shelf-life stability of Jeju black cattle beef
Objective Beef of Jeju black cattle (JBC) is considered as a healthy meat type due to its significantly higher unsaturated fatty acids (UFA). Lipid (e.g., UFA) is highly susceptible to oxidizing agents, which results in the quality deterioration and economic value loss of meat products. Therefore, development and application of novel preservative techniques is necessary to improve the shelf-life stability of high-UFA beef. The objective of this study was to assess the applicability of chitosan-based coatings in preservation of JBC beef. Methods Different coating solutions: 2% chitosan alone, and 2% chitosan containing 0.1% or 0.3% gallic acid were prepared to investigate their applicability in preservation of fresh beef during storage. Jeju black cattle beef (2-cm thick steaks) were non-coated (control) or coated with the above coating solutions, placed on trays, over-wrapped with plastic film and stored at 4°C. The microbiological indices, color, total volatile basic nitrogen (TVBN) and lipid oxidation of the beef were investigated after 1, 10, and 21 days of storage. Results Coating with 2% chitosan alone reduced the spoilage bacteria count, TVBN and thiobarbituric acid reactive substances levels in the beef compared with control during storage (p<0.05). Noticeably, coating with 2% chitosan containing 0.1% or 0.3% gallic acid was more effective on retardation of spoilage bacteria growth, lipid oxidation and discoloration in the beef compared to the chitosan coating alone over the storage period (21 days) (p<0.05). Conclusion Taken together, the combined chitosan and gallic acid coating could be used as a bio-preservative technique in the meat industry
A Triple Protostar System Formed via Fragmentation of a Gravitationally Unstable Disk
Binary and multiple star systems are a frequent outcome of the star formation
process, and as a result, almost half of all sun-like stars have at least one
companion star. Theoretical studies indicate that there are two main pathways
that can operate concurrently to form binary/multiple star systems: large scale
fragmentation of turbulent gas cores and filaments or smaller scale
fragmentation of a massive protostellar disk due to gravitational instability.
Observational evidence for turbulent fragmentation on scales of 1000~AU has
recently emerged. Previous evidence for disk fragmentation was limited to
inferences based on the separations of more-evolved pre-main sequence and
protostellar multiple systems. The triple protostar system L1448 IRS3B is an
ideal candidate to search for evidence of disk fragmentation. L1448 IRS3B is in
an early phase of the star formation process, likely less than 150,000 years in
age, and all protostars in the system are separated by 200~AU. Here we
report observations of dust and molecular gas emission that reveal a disk with
spiral structure surrounding the three protostars. Two protostars near the
center of the disk are separated by 61 AU, and a tertiary protostar is
coincident with a spiral arm in the outer disk at a 183 AU separation. The
inferred mass of the central pair of protostellar objects is 1 M,
while the disk surrounding the three protostars has a total mass of 0.30
M_{\sun}. The tertiary protostar itself has a minimum mass of 0.085
M. We demonstrate that the disk around L1448 IRS3B appears susceptible
to disk fragmentation at radii between 150~AU and 320~AU, overlapping with the
location of the tertiary protostar. This is consistent with models for a
protostellar disk that has recently undergone gravitational instability,
spawning one or two companion stars.Comment: Published in Nature on Oct. 27th. 24 pages, 8 figure
Overexpression of LCMR1 is significantly associated with clinical stage in human NSCLC
<p>Abstract</p> <p>Background</p> <p>Lung cancer is one of the most common human cancers and the leading cause of cancer death worldwide. The identification of lung cancer associated genes is essential for lung cancer diagnosis and treatment.</p> <p>Methods</p> <p>Differential Display-PCR technique was used to achieve the novel cDNA, which were then verified by real-time PCR. Northern blot was utilized to observe the expression of LCMR1 in different human tissues. 84 cases human NSCLC tissues and normal counterparts were analyzed for the expression of LCMR1 by immunohistochemistry.</p> <p>Results</p> <p>A novel 778-bp cDNA fragment from human large cell lung carcinoma cell lines 95C and 95D was obtained, and named <it>LCMR1 </it>(Lung Cancer Metastasis Related protein 1). LCMR1 was differentially expressed in different human tissues. LCMR1 was strongly overexpressed in NSCLC and its expression was significantly associated with clinical stage.</p> <p>Conclusion</p> <p>Our data indicated that <it>LCMR1</it>, strongly overexpressed in NSCLC, might have applications in the clinical diagnosis and treatment of lung cancer.</p
Observation of an Exotic Baryon in Exclusive Photoproduction from the Deuteron
In an exclusive measurement of the reaction , a
narrow peak that can be attributed to an exotic baryon with strangeness
is seen in the invariant mass spectrum. The peak is at
GeV/c with a measured width of 0.021 GeV/c FWHM, which is largely
determined by experimental mass resolution. The statistical significance of the
peak is . The mass and width of the observed peak are
consistent with recent reports of a narrow baryon by other experimental
groups.Comment: 5 pages, 5 figure
Measurement of Beam-Spin Asymmetries for Deep Inelastic Electroproduction
We report the first evidence for a non-zero beam-spin azimuthal asymmetry in
the electroproduction of positive pions in the deep-inelastic region. Data have
been obtained using a polarized electron beam of 4.3 GeV with the CLAS detector
at the Thomas Jefferson National Accelerator Facility (JLab). The amplitude of
the modulation increases with the momentum of the pion relative to
the virtual photon, , with an average amplitude of for range.Comment: 5 pages, RevTEX4, 3 figures, 2 table
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