2,249 research outputs found
Vibrations of closed-shell Lennard-Jones icosahedral and cuboctahedral clusters and their effect on the cluster ground state energy
Vibrational spectra of closed shell Lennard-Jones icosahedral and
cuboctahedral clusters are calculated for shell numbers between 2 and 9.
Evolution of the vibrational density of states with the cluster shell number is
examined and differences between icosahedral and cuboctahedral clusters
described. This enabled a quantum calculation of quantum ground state energies
of the clusters in the quasiharmonic approximation and a comparison of the
differences between the two types of clusters. It is demonstrated that in the
quantum treatment, the closed shell icosahedral clusters binding energies
differ from those of cuboctahedral clusters more than is the case in classical
treatment
Phenotypic plasticity of carbon fixation stimulates cyanobacterial blooms at elevated CO2
Although phenotypic plasticity is a widespread phenomenon, its implications for species responses to climate change are not well understood. For example, toxic cyanobacteria can form dense surface blooms threatening water quality in many eutrophic lakes, yet a theoretical framework to predict how phenotypic plasticity affects bloom development at elevated pCO2 is still lacking. We measured phenotypic plasticity of the carbon fixation rates of the common bloom-forming cyanobacterium Microcystis. Our results revealed a 1.8- to 5-fold increase in the maximum CO2 uptake rate of Microcystis at elevated pCO2, which exceeds CO2 responses reported for other phytoplankton species. The observed plasticity was incorporated into a mathematical model to predict dynamic changes in cyanobacterial abundance. The model was successfully validated by laboratory experiments and predicts that acclimation to high pCO2 will intensify Microcystis blooms in eutrophic lakes. These results indicate that this harmful cyanobacterium is likely to benefit strongly from rising atmospheric pCO2
3-methylhistidine as an Indicator for Protein Beakdown: An Experimental Model in Male Capra hircu
The role of the amino acid 3-methylhistidine as an indicator of protein breakdown and weight loss is often suggested. Despite existing information for other animal species, little is known about the actual levels of 3-methyhistidine in the serum of less studied domestic species such as the goat. We have evaluated the 3-methyhistidine serum concentrations in young Boer goat bucks subjected to two distinct feeding regimens: winter-grass hay with or without supplementation. Non-supplemented animals had a negative nitrogen balance and experienced weight loss throughout the experiment and significantly higher concentrations of 3-methyhistidine than supplemented animals that had a slight increase in live weight. This amino acid can be considered a valid indicator of protein breakdown and weight decrease in male goats. Serum 3-methylhistidine concentrations in adequately fed male goats were similar throughout the assay (20-40 μmol/l) whereas in weight-losing animals, concentrations of up to 170μmol/l can be expected.
Nuclear medicine imaging of multiple myeloma, particularly in the relapsed setting
Multiple myeloma (MM) is characterized by a monoclonal plasma cell population in the bone marrow. Lytic lesions occur in up to 90 % of patients. For many years, whole-body X-ray (WBX) was the method of choice for detecting skeleton abnormalities. However, the value of WBX in relapsing disease is limited because lesions persist post-treatment, which restricts the capacity to distinguish between old, inactive skeletal lesions and new, active ones. Therefore, alternative techniques are necessary to visualize disease activity. Modern imaging techniques such as magnetic resonance imaging, positron emission tomography and computed tomography offer superior detection of myeloma bone disease and extramedullary manifestations. In particular, the properties of nuclear imaging enable the identification of disease activity by directly targeting the specific cellular properties of malignant plasma cells. In this review, an overview is provided of the effectiveness of radiopharmaceuticals that target metabolism, surface receptors and angiogenesis. The available literature data for commonly used nuclear imaging tracers, the promising first results of new tracers, and our pilot work indicate that a number of these radiopharmaceutical applications can be used effectively for staging and response monitoring of relapsing MM patients. Moreover, some tracers can potentially be used for radio immunotherapy
Oto-spondylo-megaepiphyseal dysplasia (OSMED): Clinical description of three patients homozygous for a missense mutation in the COL11A2 gene
In vitro drug sensitivity of normal peripheral blood lymphocytes and childhood leukaemic cells from bone marrow and peripheral blood.
In vitro drug sensitivity of leukaemic cells might be influenced by the contamination of such a sample with non-malignant cells and the sample source. To study this, sensitivity of normal peripheral blood (PB) lymphocytes to a number of cytostatic drugs was assessed with the MTT assay. We compared this sensitivity with the drug sensitivity of leukaemic cells of 38 children with acute lymphoblastic leukaemia. We also studied a possible differential sensitivity of leukaemic cells from bone marrow (BM) and PB. The following drugs were used: Prednisolone, dexamethasone, 6-mercaptopurine, 6-thioguanine, cytosine arabinoside, vincristine, vindesine, daunorubicin, doxorubicin, mafosfamide (Maf), 4-hydroperoxy-ifosfamide, teniposide, mitoxantrone, L-asparaginase, methotrexate and mustine. Normal PB lymphocytes were significantly more resistant to all drugs tested, except to Maf. Leukaemic BM and PB cells from 38 patients (unpaired samples) showed no significant differences in sensitivity to any of the drugs. Moreover, in 11 of 12 children with acute leukaemia of whom we investigated simultaneously obtained BM and PB (paired samples), their leukaemic BM and PB cells showed comparable drug sensitivity profiles. In one patient the BM cells were more sensitive to most drugs than those from the PB, but the actual differences in sensitivity were small. We conclude that the contamination of a leukaemic sample with normal PB lymphocytes will influence the results of the MTT assay. The source of the leukaemic sample, BM or PB, does not significantly influence the assay results
Entropic effects on the Size Evolution of Cluster Structure
We show that the vibrational entropy can play a crucial role in determining
the equilibrium structure of clusters by constructing structural phase diagrams
showing how the structure depends upon both size and temperature. These phase
diagrams are obtained for example rare gas and metal clusters.Comment: 5 pages, 3 figure
A Comparative Study on the Reactivity of Various Ketohexoses to Furanics in Methanol
The acid-catalysed dehydration of the four 2-ketohexoses (fructose, sorbose, tagatose and psicose) to furanics was studied in methanol (65 gL(-1) substrate concentration, 17 and 34 mm sulfuric acid, 100 degrees C) with Avantium high-throughput technology. Significant differences in the reactivities of the hexoses and yields of 5-hydroxymethylfurfural (HMF) and its methyl ether (MMF) were observed. Psicose and tagatose were the most reactive, and psicose also afforded the highest combined yield of MMF and HMF of approximately 55% at 96% sugar conversion. Hydroxyacetylfuran and its corresponding methyl ether were formed as byproducts, particularly for sorbose and tagatose, with a maximum combined yield of 8% for sorbose. The formation of hydroxyacetylfuran was studied through C-13 NMR spectroscopy with labelled sorbose, which provided new insights into the reaction mechanism
Post-Conflict Affiliation by Chimpanzees with Aggressors: Other-Oriented versus Selfish Political Strategy
Consolation, i.e., post-conflict affiliation directed from bystanders to recent victims of aggression, has recently acquired an important role in the debate about empathy in great apes. Although similar contacts have been also described for aggressors, i.e., appeasement, they have received far less attention and their function and underlying mechanisms remain largely unknown. An exceptionally large database of spontaneous conflict and post-conflict interactions in two outdoor-housed groups of chimpanzees lends support to the notion that affiliation toward aggressors reduces the latter's aggressive tendencies in that further aggression was less frequent after the occurrence of the affiliation. However, bystander affiliation toward aggressors occurred disproportionally between individuals that were socially close (i.e., affiliation partners) which suggest that it did not function to protect the actor itself against redirected aggression. Contrary to consolation behavior, it was provided most often by adult males and directed toward high ranking males, whereas females engaged less often in this behavior both as actors and recipients, suggesting that affiliation with aggressors is unlikely to be a reaction to the distress of others. We propose that bystander affiliation toward aggressors may function to strengthen bonds between valuable partners, probably as part of political strategies. Our findings also suggest that this post-conflict behavior may act as an alternative to reconciliation, i.e., post-conflict affiliation between opponents, in that it is more common when opponents fail to reconcile
PENYALAHGUNAAN ASET NEGARA DALAM BENTUK JARINGAN SATELIT UNTUK KEPENTINGAN KORPORASI DIHUBUNGKAN DENGAN UNDANGUNDANG NOMOR 36 TAHUN 1999 TENTANG TELEKOMUNIKASI JO UNDANGUNDANG NOMOR 20 TAHUN 2001 TENTANG TINDAK PIDANA KORUPSI
telekomunikasi sebagaimana dilakukan oleh IM2. IM2 telah menyalahgunakan pita
frekuensi 2.1 Ghz, dan secara melawan hukum beroperasi pada jaringan tersebut sehingga
menimbulkan kerugian negara. Berdasarkan hal tersebut maka penulis tertarik meneliti,
bagaimana Undang-Undang Telekomunikasi jo Peraturan Menteri Komunikasi dan
Informatika dan Undang-Undang Tindak Pidana Korupsi mengatur mekanisme pemanfaatan
aset negara berupa jaringan satelit, mengapa aset negara berupa jaringan satelit kerap kali
disalahgunakan didalam pemanfaatannya oleh korporasi, serta bagaimana upaya yang dapat
dilakukan untuk melindungi aset negara dalam bentuk jaringan satelit terhadap
penyalahgunaan yang dilakukan oleh korporasi.
Penelitian ini menggunakan spesifikasi penelitian yang bersifat deskriftif analitis
dengan pendekatan yuridis normatif dibantu yuridis empiris, data yang diperlukan dalam
penelitian ini dikumpulkan melalui studi kepustakaan dan studi lapangan, kemudian
dianalisis menggunakan teknik analisis data berupa yuridis kualitatif.
Pemanfaatan aset negara berupa jaringan satelit melalui pita frekuensi merupakan
salah satu hak yang dalam pemanfaatannya diatur oleh peraturan perundang-undangan agar
tercipta keadilan, kepastian dan ketertiban, keamanan, keseimbangan, perlindungan dan
pemeliharaan dalam pemanfataannya. Jaringan satelit yang merupakan jaringan satelit aset
negara pemanfaatannya mensyaratkan izin dan pembayaran tarif tertentu, sehingga
konsekuensinya ketika terjadi penyalahgunaan pemanfaatan jaringan satelit, negara akan
mengalami kerugian. Aset negara berupa jaringan satelit kerap kali disalahgunakan didalam
pemanfaatannya oleh korporasi disebabkan beberapa faktor diantaranya faktor hukum itu
sendiri dalam hal ini peraturan perundang-undangannya, faktor penegak hukum, faktor sarana
atau fasilitas yang mendukung pengawasan dan penegakan hukum itu sendiri, faktor
masyarakat, yakni lingkungan dimana hukum tersebut berlaku atau diterapkan, dalam hal ini
yaitu lingkungan korporasi, faktor kebudayaan yakni kurangnya kesadaran hukum korporasi
dalam upaya pemanfaatan aset negara secara berkeadilan dan tertib sesuai peraturan
perundang-undangan yang berlaku, dimana pemanfaatan yang tidak secara berkeadilan akan
membawa negara menuju kepada kehancuran. Upaya yang dapat dilakukan untuk melindungi
aset negara dalam bentuk jaringan satelit terhadap penyalahgunaan yang dilakukan oleh
korporasi harus berangkat dari beberapa faktor yang menjadi penyebab penyalahgunaan
pemanfaatan jaringan satelit diantaranya yaitu melalui upaya preventif berupa revisi
perunang-undangan, pengawasan, sosialisasi sert upaya represif berupa penegakan hukum.
Penegakan hukum harus dilaksanakan tanpa pandang bulu, sebagai bentuk keyakinan atas
doktrin hukum, bahwa setiap orang mempunyai kedudukan yang sama di depan hukum.
Kata Kunci: Penyalahgunaan Aset Negara, Jaringan Sateli
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