bluuebunny/crossref_metadata_2025 huggingface dataset:
Creation of a novel telomere-cutting endonuclease based on the EN domain of telomere-specific non-long terminal repeat retrotransposon, TRAS1
Authors: Yoshitake Kazutoshi , Aoyagi Hideyuki , Fujiwara Haruhiko
Published: April 2010

Background

The ends of chromosomes, termed telomeres consist of repetitive DNA. The telomeric sequences shorten with cell division and, when telomeres are critically abbreviated, cells stop proliferating. However, in cancer cells, by the expression of telomerase which elongates telomeres, the cells can continue proliferating. Many approaches for telomere shortening have been pursued in the past, but to our knowledge, cutting telomeres in vivo has not so far been demonstrated. In addition, there is lack of information on the cellular effects of telomere shortening in human cells.

Results

Here, we created novel chimeric endonucleases to cut telomeres by fusing the endonuclease domain (TRAS1EN) of the silkworm's telomere specific non-long terminal repeat retrotransposon TRAS1 to the human telomere-binding protein, TRF1. An in vitro assay demonstrated that the TRAS1EN-TRF1 chimeric endonucleases (T-EN and EN-T) cut the human (TTAGGG)n repeats specifically. The concentration of TRAS1EN-TRF1 chimeric endonucleases necessary for the cleavage of (TTAGGG)n repeats was about 40-fold lower than that of TRAS1EN alone. When TRAS1EN-TRF1 endonucleases were introduced into human U2OS cancer cells using adenovirus vectors, the enzymes localized at telomeres of nuclei, cleaved and shortened the telomeric DNA by double-strand breaks. When human U2OS and HFL-1 fibroblast cells were infected with EN-T recombinant adenovirus, their cellular proliferation was suppressed for about 2 weeks after infection. In contrast, the TRAS1EN mutant (H258A) chimeric endonuclease fused with TRF1 (ENmut-T) did not show the suppression effect. The EN-T recombinant adenovirus induced telomere shortening in U2OS cells, activated the p53-dependent pathway and caused the senescence associated cellular responses, while the ENmut-T construct did not show such effects.

Conclusions

A novel TRAS1EN-TRF1 chimeric endonuclease (EN-T) cuts the human telomeric repeats (TTAGGG)n specifically in vitro and in vivo. Thus, the chimeric endonuclease which is expressed from an adenoviral vector can suppress cell proliferation of cancer cells.
Prospective monitoring of cefepime in intensive care unit adult patients
Authors: Chapuis Thomas M , Giannoni Eric , Majcherczyk Paul A , Chioléro René , Schaller Marie-Denise , Berger Mette M , Bolay Saskia , Décosterd Laurent A , Bugnon Denis , Moreillon Philippe
Published: April 2010

Introduction

Cefepime has been associated with a greater risk of mortality than other beta-lactams in patients treated for severe sepsis. Hypotheses for this failure include possible hidden side-effects (for example, neurological) or inappropriate pharmacokinetic/pharmacodynamic (PK/PD) parameters for bacteria with cefepime minimal inhibitory concentrations (MIC) at the highest limits of susceptibility (8 mg/l) or intermediate-resistance (16 mg/l) for pathogens such asEnterobacteriaceae,Pseudomonas aeruginosaandStaphylococcus aureus. We examined these issues in a prospective non-interventional study of 21 consecutive intensive care unit (ICU) adult patients treated with cefepime for nosocomial pneumonia.

Methods

Patients (median age 55.1 years, range 21.8 to 81.2) received intravenous cefepime at 2 g every 12 hours for creatinine clearance (CLCr) ≥ 50 ml/min, and 2 g every 24 hours or 36 hours for CLCr< 50 ml/minute. Cefepime plasma concentrations were determined at several time-points before and after drug administration by high-pressure liquid chromatography. PK/PD parameters were computed by standard non-compartmental analysis.

Results

Seventeen first-doses and 11 steady states (that is, four to six days after the first dose) were measured. Plasma levels varied greatly between individuals, from two- to three-fold at peak-concentrations to up to 40-fold at trough-concentrations. Nineteen out of 21 (90%) patients had PK/PD parameters comparable to literature values. Twenty-one of 21 (100%) patients had appropriate duration of cefepime concentrations above the MIC (T>MIC≥ 50%) for the pathogens recovered in this study (MIC ≤ 4 mg/l), but only 45 to 65% of them had appropriate coverage for potential pathogens with cefepime MIC ≥ 8 mg/l. Moreover, 2/21 (10%) patients with renal impairment (CLCr< 30 ml/minute) demonstrated accumulation of cefepime in the plasma (trough concentrations of 20 to 30 mg/l) in spite of dosage adjustment. Both had symptoms compatible with non-convulsive epilepsy (confusion and muscle jerks) that were not attributed to cefepime-toxicity until plasma levels were disclosed to the caretakers and symptoms resolved promptly after drug arrest.

Conclusions

These empirical results confirm the suspected risks of hidden side-effects and inappropriate PK/PD parameters (for pathogens with upper-limit MICs) in a population of ICU adult patients. Moreover, it identifies a safety and efficacy window for cefepime doses of 2 g every 12 hours in patients with a CLCr≥ 50 ml/minute infected by pathogens with cefepime MICs ≤ 4 mg/l. On the other hand, prompt monitoring of cefepime plasma levels should be considered in case of lower CLCror greater MICs.
Gonadotropins Regulate Rat Testicular Tight Junctions in Vivo
Authors: McCabe Mark J. , Tarulli Gerard A. , Meachem Sarah J. , Robertson David M. , Smooker Peter M. , Stanton Peter G.
Published: April 2010

Sertoli cell tight junctions (TJs) are an essential component of the blood-testis barrier required for spermatogenesis; however, the role of gonadotropins in their maintenance is unknown. This study aimed to investigate the effect of gonadotropin suppression and short-term replacement on TJ function and TJ protein (occludin and claudin-11) expression and localization, in an adult rat model in vivo. Rats (n = 10/group) received the GnRH antagonist, acyline, for 7 wk to suppress gonadotropins. Three groups then received for 7 d: 1) human recombinant FSH, 2) human chorionic gonadotropin (hCG) and rat FSH antibody (to study testicular androgen stimulation alone), and 3) hCG alone (to study testicular androgen and pituitary FSH production). TJ proteins were assessed by real-time PCR, Western blot analysis, and immunohistochemistry, whereas TJ function was assessed with a biotin permeation tracer. Acyline treatment significantly reduced testis weights, serum androgens, LH and FSH, and adluminal germ cells (pachytene spermatocyte, round and elongating spermatids). In contrast to controls, acyline induced seminiferous tubule permeability to biotin, loss of tubule lumens, and loss of occludin, but redistribution of claudin-11, immunostaining. Short-term hormone replacement stimulated significant recoveries in adluminal germ cell numbers. In hCG ± FSH antibody-treated rats, occludin and claudin-11 protein relocalized at the TJ, but such relocalization was minimal with FSH alone. Tubule lumens also reappeared, but most tubules remained permeable to biotin tracer, despite the presence of occludin. It is concluded that gonadotropins maintain Sertoli cell TJs in the adult rat via a mechanism that includes the localization of occludin and claudin-11 at functional TJs.
New Therapeutic and Biomarker Discovery for Peripheral Diabetic Neuropathy: PARP Inhibitor, Nitrotyrosine, and Tumor Necrosis Factor-α
Authors: Drel Viktor R. , Lupachyk Sergey , Shevalye Hanna , Vareniuk Igor , Xu Weizheng , Zhang Jie , Delamere Nicholas A. , Shahidullah Mohammad , Slusher Barbara , Obrosova Irina G.
Published: April 2010

This study evaluated poly(ADP-ribose) polymerase (PARP) inhibition as a new therapeutic approach for peripheral diabetic neuropathy using clinically relevant animal model and endpoints, and nitrotyrosine (NT), TNF-α, and nitrite/nitrate as potential biomarkers of the disease. Control and streptozotocin-diabetic rats were maintained with or without treatment with orally active PARP inhibitor 10-(4-methyl-piperazin-1-ylmethyl)-2H-7-oxa-1,2-diaza-benzo[de]anthracen-3-one (GPI-15,427), 30 mg kg−1 d−1, for 10 wk after first 2 wk without treatment. Therapeutic efficacy was evaluated by poly(ADP-ribosyl)ated protein expression (Western blot analysis), motor and sensory nerve conduction velocities, and tibial nerve morphometry. Sciatic nerve and spinal cord NT, TNF-α, and nitrite/nitrate concentrations were measured by ELISA. NT localization in peripheral nervous system was evaluated by double-label fluorescent immunohistochemistry. A PARP inhibitor treatment counteracted diabetes-induced motor and sensory nerve conduction slowing, axonal atrophy of large myelinated fibers, and increase in sciatic nerve and spinal cord NT and TNF-α concentrations. Sciatic nerve NT and TNF-α concentrations inversely correlated with motor and sensory nerve conduction velocities and myelin thickness, whereas nitrite/nitrate concentrations were indistinguishable between control and diabetic groups. NT accumulation was identified in endothelial and Schwann cells of the peripheral nerve, neurons, astrocytes, and oligodendrocytes of the spinal cord, and neurons and glial cells of the dorsal root ganglia. The findings identify PARP as a compelling drug target for prevention and treatment of both functional and structural manifestations of peripheral diabetic neuropathy and provide rationale for detailed evaluation of NT and TNF-α as potential biomarkers of its presence, severity, and progression.
Genistein Aglycone Does Not Affect Thyroid Function: Results from a Three-Year, Randomized, Double-Blind, Placebo-Controlled Trial
Authors: Bitto Alessandra , Polito Francesca , Atteritano Marco , Altavilla Domenica , Mazzaferro Susanna , Marini Herbert , Adamo Elena Bianca , D'Anna Rosario , Granese Roberta , Corrado Francesco , Russo Silvia , Minutoli Letteria , Squadrito Francesco
Published: April 2010

Context and Objective: Genistein aglycone positively affects postmenopausal symptoms. However, questions about its long-term safety on the thyroid gland still remain.

Design: The parent study was a randomized, double-blind, placebo-controlled trial involving 389 osteopenic, postmenopausal women for 24 months. A subcohort (138 patients) continued therapy for an additional year.

Setting: Patients received ambulatory care.

Patients and Interventions: Participants received 54 mg of genistein aglycone daily (n = 71) or placebo (n = 67), plus calcium and vitamin D3 at therapeutic doses. Circulating thyroid hormones (TSH, free T3, free T4) and autoantibodies (thyroid peroxidase, thyroglobulin, and thyroid microsomal antigen) were assessed in 40 genistein and 37 placebo subjects who completed 3 yr. Thyroid hormone receptor (THRα and THRβ) and retinoid receptor (RARα, RARγ, and RXRα) expression from peripheral blood monocytes was also evaluated at baseline, 12, 24, and 36 months in all 3-yr completers.

Results: Genistein administration over 3 yr did not affect serum thyroid hormones or autoantibodies. In addition, there were no differences in THRα, THRβ, RARα, RARγ, or RXRα mRNA expression between groups.

Conclusion: These data suggest that genistein aglycone intake does not significantly increase the risk of clinical or subclinical hypothyroidism at the dose of 54 mg/d.
Mesodermal Wnt signaling organizes the neural plate via Meis3
Authors: Elkouby Yaniv M. , Elias Sarah , Casey Elena S. , Blythe Shelby A. , Tsabar Nir , Klein Peter S. , Root Heather , Liu Karen J. , Frank Dale
Published: April 2010

In vertebrates, canonical Wnt signaling controls posterior neural cell lineage specification. Although Wnt signaling to the neural plate is sufficient for posterior identity, the source and timing of this activity remain uncertain. Furthermore, crucial molecular targets of this activity have not been defined. Here, we identify the endogenous Wnt activity and its role in controlling an essential downstream transcription factor, Meis3. Wnt3a is expressed in a specialized mesodermal domain, the paraxial dorsolateral mesoderm, which signals to overlying neuroectoderm. Loss of zygotic Wnt3a in this region does not alter mesoderm cell fates, but blocks Meis3 expression in the neuroectoderm, triggering the loss of posterior neural fates. Ectopic Meis3 protein expression is sufficient to rescue this phenotype. Moreover, Wnt3a induction of the posterior nervous system requires functional Meis3 in the neural plate. Using ChIP and promoter analysis, we show that Meis3 is a direct target of Wnt/β-catenin signaling. This suggests a new model for neural anteroposterior patterning, in which Wnt3a from the paraxial mesoderm induces posterior cell fates via direct activation of a crucial transcription factor in the overlying neural plate.
Ets1 is required for proper migration and differentiation of the cardiac neural crest
Authors: Gao Zhiguang , Kim Gene H. , Mackinnon Alexander C. , Flagg Alleda E. , Bassett Brett , Earley Judy U. , Svensson Eric C.
Published: April 2010

Defects in cardiac neural crest lead to congenital heart disease through failure of cardiac outflow tract and ventricular septation. In this report, we demonstrate a previously unappreciated role for the transcription factor Ets1 in the regulation of cardiac neural crest development. When bred onto a C57BL/6 genetic background, Ets1−/− mice have a nearly complete perinatal lethality. Histologic examination of Ets1−/− embryos revealed a membranous ventricular septal defect and an abnormal nodule of cartilage within the heart. Lineage-tracing experiments in Ets1−/− mice demonstrated that cells of the neural crest lineage form this cartilage nodule and do not complete their migration to the proximal aspects of the outflow tract endocardial cushions, resulting in the failure of membranous interventricular septum formation. Given previous studies demonstrating that the MEK/ERK pathway directly regulates Ets1 activity, we cultured embryonic hearts in the presence of the MEK inhibitor U0126 and found that U0126 induced intra-cardiac cartilage formation, suggesting the involvement of a MEK/ERK/Ets1 pathway in blocking chondrocyte differentiation of cardiac neural crest. Taken together, these results demonstrate that Ets1 is required to direct the proper migration and differentiation of cardiac neural crest in the formation of the interventricular septum, and therefore could play a role in the etiology of human congenital heart disease.
Dendritic cell podosomes are protrusive and invade the extracellular matrix using metalloproteinase MMP-14
Authors: Gawden-Bone Christian , Zhou Zhongjun , King Emma , Prescott Alan , Watts Colin , Lucocq John
Published: April 2010

Podosomes are spot-like actin-rich structures formed at the ventral surface of monocytic and haematopoietic cells. Podosomes degrade extracellular matrix and are proposed to be involved in cell migration. A key question is whether podosomes form protrusions similar to the invadopodia of cancer cells. We characterised podosomes of immature dendritic cells using electron microscopy combined with both conventional and novel high-resolution structured illumination light microscopy. Dendritic cell podosomes are composed of actin foci surrounded by a specialised ring region that is rich in material containing paxillin. We found that podosomes were preferential sites for protrusion into polycarbonate filters impregnated with crosslinked gelatin, degrading up to 2 μm of matrix in 24 hours. Podosome-associated uptake of colloidal gold-labelled gelatin matrix appeared to occur via large phagosome-like structures or narrow tubular invaginations. The motor protein myosin-II was excluded from ring or core regions but was concentrated around them and the myosin-II inhibitor Blebbistatin reduced the length of podosome protrusions. Finally, we found that degradation, protrusion and endocytosis in this system are dependent on the matrix metalloproteinase MMP-14. We propose that podosomes mediate migration of dendritic cells through tissues by means of myosin-II-dependent protrusion coupled to MMP-14-dependent degradation and endocytosis.
Activity of protein kinase CK2 uncouples Bid cleavage from caspase-8 activation
Authors: Hellwig Christian T. , Ludwig-Galezowska Agnieszka H. , Concannon Caoimhin G. , Litchfield David W. , Prehn Jochen H. M. , Rehm Markus
Published: April 2010

In the present study, we quantitatively analysed the interface between apoptosis initiation and execution by determining caspase-8 activation, Bid cleavage and mitochondrial engagement (onset of mitochondrial depolarisation) in individual HeLa cervical cancer cells following exposure to tumour-necrosis-factor-related apoptosis-inducing ligand (TRAIL). Employing resonance-energy-transfer probes containing either the caspase-8 recognition site IETD or full-length Bid, we observed a significant delay between the times of caspase-8 activation and Bid cleavage, suggesting the existence of control steps separating these two processes. Subsequent analyses suggested that the divergence of caspase-8 activation and Bid cleavage are critically controlled by kinase signalling: inhibiting protein kinase CK2 by using 5,6-dichloro-l-(β-D-ribofuranosyl-1)-benzimidazole (DRB) or by overexpression of a dominant-negative CK2α catalytic subunit largely eliminated the lag time between caspase-8 activation and Bid cleavage. We conclude that caspase-8 activation and Bid cleavage are temporally uncoupled events, providing transient tolerance to caspase-8 activities.
N-linked glycosylation is required for optimal proteolytic activation of membrane-bound transcription factor CREB-H
Authors: Chan Chi-Ping , Mak To-Yuen , Chin King-Tung , Ng Irene Oi-Lin , Jin Dong-Yan
Published: April 2010

CREB-H is a liver-enriched bZIP transcription factor of the CREB3 subfamily. CREB-H is activated by intramembrane proteolysis that removes a C-terminal transmembrane domain. Aberrant expression of CREB-H is implicated in liver cancer. In this study we characterized N-linked glycosylation of CREB-H in the luminal domain at the C-terminus. We found that CREB-H is modified at three N-linked glycosylation sites in this region. Disruption of all three sites by site-directed mutagenesis completely abrogated N-linked glycosylation of CREB-H. The unglycosylated mutant of CREB-H was not unstable, unfolded or aggregated. Upon stimulation with an activator of intramembrane proteolysis such as brefeldin A and KDEL-tailed site 1 protease, unglycosylated or deglycosylated CREB-H was largely uncleaved, retained in an inactive form in the endoplasmic reticulum, and less capable of activating transcription driven by unfolded protein response element or C-reactive protein promoter. Taken together, our findings suggest that N-linked glycosylation is required for full activation of CREB-H through intramembrane proteolysis. Our work also reveals a novel mechanism for the regulation of CREB-H-dependent transcription.
A Binomial Approach to Selecting Optimum Working Interest: Corporate Risk and Corporate Confidence
Authors: MacKay J. A. , Lerche I.
Published: April 2010

Current methods for determining the optimum working interest (OWI) one should take in an exploration project are beholden to underlying basic utility theory. As such they suffer from the generic consequences that: the OWI is never guaranteed to be always less than unity as it must be; that the OWI does not always increase as the net present value of a project is increased as it should; and that the OWI is automatically set to zero when the expected value of the project is less than zero, despite there being an uncertainty on the expected value that could still allow a profitable outcome. As a consequence of these drawbacks, here we set up a binomial procedure for ascertaining the OWI, which method does not suffer from any of the utility-based problems. Several illustrations indicate how the binomial enhancement operates in reality. In addition, one can also compute the corporate confidence in a project using this new approach, and determine the corresponding apparent confidence of any utility-based procedure for determining OWI. This binomial procedure for determining OWI and corporate confidence is, therefore, a reasonable alternative over previously available methods.
A Binomial Approach to Selecting Optimum Working Interest: Corporate Risk and Corporate Confidence II. Uncertain Assessments and Resolution of Worth
Authors: MacKay J. A. , Lerche I.
Published: April 2010

This second paper in the series explores the influence of uncertain values for costs, success probability and net present value on the assessment of optimum working interest (OWI) and corporate confidence probability in an exploration project based on the binomial definition of working interest in relation to corporate confidence. It is shown that one obtains a distribution range of optimum working interest together with the relative contributions of each of the uncertain parameters to the range of OWI and also on the corporate confidence. In this way one can determine which of the uncertain parameters to attempt to define better in order to minimize the range of uncertainty on either the optimum working interest or the corporate confidence should one choose to do so. The decision of whether to pursue such a narrowing of the uncertainty ranges depends on whether a corporation is prepared to accept the range of outcomes as not worthy of such improvement or whether the corporation thinks the range of uncertainty of, say, the optimum working interest is so large that a concerted effort should be made to improve uncertain parameter ranges. Numerical illustrations are give to show how the procedure works in practise.
A Binomial Approach to Selecting Optimum Working Interest: Corporate Risk and Corporate Confidence III. Ignorance is Not Bliss
Authors: MacKay J. A. , Lerche I.
Published: April 2010

This third paper in the series is concerned with the situation in which one has virtually no idea whether an exploration opportunity is likely to be a money winner or just awful. Using a variant of the binomial method accounting for the probability that a well will result in successful hydrocarbon finding after a series of dry holes, we show that one can assess the corporate confidence and associated optimum working interest one should take in such an exploration opportunity when one ignores all information about the net present value (NPV). When a corporation wishes to modify the basic pattern to allow for an NPV, and to include a required corporate worth for the opportunity, we show how the corporate confidence and/or the optimum working interest have to be altered to allow for such a factor. When the corporation knows only a low value for the NPV, which is unprofitable, and a high value, which is extremely profitable, we show how one can incorporate this broad range of possibilities within the same binomial framework to assess the likely distribution of optimum working interest (for a fixed corporate confidence) or corporate confidence distribution (for a fixed working interest) for choices of corporate required worth.

These calculations allow a corporation to be more sharply focused on the working interest it might wish to take in relation to its corporate confidence that the unknown opportunity NPV might just turn out to be highly profitable, without overly committing too great a fraction of the corporate resources to such speculative ventures.
Oil and Natural Gas Transport Systems, Trade and Consumption Trends in Turkey
Authors: Balat Mustafa
Published: April 2010

Turkey is a rapidly growing energy consumer in its own right. Turkey has experienced extremely sharp economic growth in recent years, which was largely achieved through a rapidly increasing population. Due to its demographic and economic growth, Turkey constitutes a major energy market. Domestic energy production has not exceeded half of energy demand. Crude oil remains the main energy source. In 2001, oil consumption was 0.6 million barrels per day. The share of oil is the largest, ranging from 46.3% in 1985 to 43 % in 2001. Domestic natural gas (NG) production is very small and almost all NG is imported. In 2001, NG production was around 312 million cubic meters (mcm), while imports were around 16.34 billion cubic meters (bcm). Current gas production in Turkey meets 1.9% of domestic consumption requirements. Turkey's demand for NG is estimated to rise to 55 bcm by 2010 and 83 bcm by 2020.
Turkey's Water Resources and Hydropower Potential
Authors: Demirbaş Ayhan , Bakiş Recep
Published: April 2010

The aim of this paper is to investigate water resources in Turkey. Annual rainfall varies from 220 mm to 2500 mm with an average of 643 mm, which means total volume of 501 km3 and average annual potential of surface water is 186 km3 and 95 km3 of this amount potential can be feasibly developed. Ground water reservoirs are estimated to be around 12 km3. As a result of construction of 700 dams, with different types, purposes and sizes, 140 km3 of water is being stored in the reservoirs. Total hydropower potential of Turkey is annually 433,000 GWh. Almost 50% of the total potential is technically exploitable, and 29% is (122,322 GWh/year) economically exploitable.
Baku-Tbilisi Ceyhan Oil Pipeline (BTC) Project and Turkey: Investments, Future Developments and Environmental Impacts
Authors: Balat Mustafa , Ersoy Gulyeter
Published: April 2010

Baku-Tbilisi-Ceyhan Oil Pipeline (BTC) is one of the world's major energy projects. The Turkish section of the BTC pipeline will be approximately 1.070 km in length and will terminate at a new storage and export terminal (BTC Marine Terminal). It is expected that 30% of the pipeline cost will be financed by the investors with the remaining 70% will come from the U.S. Exim Bank, Japan's Exim Bank, the International Finance Corporation, and the EBRD. Unfortunately for Turkey, the costs of constructing a Baku-Ceyhan pipeline are enormous: the Turkish government puts the price at $2 billion, while the Azerbaijan International Operating Company (AIOC)'s estimates range far higher, at $3.5 billion.
Recent Status of Geothermal Energy Applications in Turkey
Authors: Balat Mustafa
Published: April 2010

This article considers recently status of geothermal energy in Turkey. Turkey is the 7th richest country in the world in geothermal potential. The overall geothermal potential in Turkey is about 38,000 MW. But only 2% of its potential is used. Geothermal electricity generation has a minor role in Turkey's electricity capacity as low as 0.09% but the projections foresee an improvement to 0.32% by the year of 2020. Most of the geothermal sites for electricity generation are located in Aydin–Germencik (505 K), Denizli–Kizildere (515 K), Aydin–Salavatli (444 K), Canakkale–Tuzla (446 K) and Kutahya–Simav (435 K). Turkey has increased their installed capacity over the past five years from 140 MWt to 820 MWt, most for district heating systems. This supplies heat to 51,600 equivalent residences and engineering design to supply a further 150,000 residences with geothermal heat is complete.
Turkey's Wood Reserves, Potential Trends and Future Perspectives of Wood Use
Authors: Balat Mustafa , Acici Neslihan , Ersoy Gulyeter
Published: April 2010

Wood is the major source of energy in rural Turkey. Forests and wooded land cover 20.2 million hectares (ha) of Turkey's 77 million ha and are 99 percent state owned and managed. As a result of destructive use, productive forests cover only about 6.6 million ha, equivalent to 8.5 percent of land area. The remaining 2.2 million ha consist of degraded unproductive forest cover and 11.3 million ha of wooded land. The total forest potential of Turkey is around 935 million m3 with an annual growth of about 28 million m3. Fuel wood is most likely the most important commodity coming from the forests. Fuel wood is the fourth largest source of energy in Turkey. In Turkey, fuel wood production is 17.6 mtoe, in 1999. Turkey is decreasing its consumption from 5177 Goe to 5512 Goe in 1995.
Gold Enrichment Mechanism in Crude Oils and Source Rocks in Jiyang Depression
Authors: Sun Yuzhuang , Jiao Weiwei , Zhang Shouchun , Qin Shenjun
Published: April 2010

Gold enrichment in crude oils and source rock samples has been reported in Jiyang Depression, Shengli Oilfield. In order to study the mechanism of gold enrichment, 18 samples collected around deep faults were analyzed by geochemical methods. The results indicate that the gold accumulation in Jiyang Depression is closely related to the mantle fluids and sulfur polycyclic aromatic hydrocarbon (S-PAH) in oil and source rocks. Gold elements could be from the mantle fluids and accumulated when they were carried into source rocks, especially when they encountered S-PAH. Rare earth element (REE) contents are high when gold contents are high. This phenomenon may indicate that a part of REE is also from the mantle fluids.
Migration and Distribution of Fifteen Toxic Trace Elements during the Coal Washing of the Kailuan Coalfield, Hebei Province, China
Authors: Tang Yuegang , Chang Chunxiang , Zhang Yizhong , Li Weiwei
Published: April 2010

This study mainly deals with the contents, migration and distribution of 15 toxic trace elements, including Be, Cr, Co, Ni, Cu, Zn, Ga, As, Se, Mo, T1, Pb, Th, U and Hg, in the Paleozoic coals from the Kailuan Coalfield and their washing products. The results showed that Cr, Ni, Cu, Zn, Pb and As are enriched in the raw coals. And all the 15 elements could be removed from the the raw coals to the slime. Selenium and thorium are relatively enriched in the middlings, and most of the elements, with the exception of T1, are enriched in the tailings, among which As enrichment ratio is the highest (34.4%). Accordingly, more attentions should be paid to As and Hg when tailing and coal slime are utilized. Based on maceral and mineral analysis, the authors supposed that the migration and distribution of the 15 elements during coal washing might be controlled by clay minerals and pyrites.
Geochemical Characteristics of Oils from Chepaizi Area, Northwestern Junggar Basin, China
Authors: Liu Luofu , Wang Weibin , Wu Lin , Zhao Yande , Chen Zhijun , Wang Ping , Jin Jun , Wang Weili , Meng Jianghui , Zhou Jieli , Liu Guodong
Published: April 2010

In recent years, great progress in petroleum exploration has been made obtained for Chepaizi Swell along the northwestern margin of Junggar Basin. But, the hydrocarbon sources of this area are still unknown, and this results in difficulty of determining the migration path system and migration trend. This also leads to difficulty in studying the oil-gas accumulation pattern of the area. In order to understand the oil sources, samples were systematically collected in the Swell and were analyzed for investigation of physical properties, chemical compositions and characteristics of bio-markers, carbon isotope and nitrogen compounds of the oils from Chepaizi. Through comparisons of physical and chemical characters, oils from different intervals of Chepaizi can be classified into two groups. One is the oils trapped in layers of Jurassic and below Jurassic (named as Lower Series of Strata oils), and another is those in layers of Cretaceous and above Cretaceous (named as Upper Series of Strata oils). Oils from the same group have similar densities, viscosities, group compositions and characteristics of saturated hydrocarbon, bio-marker and carbon isotope, while the oils from different groups are obviously different for the above-mentioned parameters. By fine oil-oil correlation, one can know that the lower-layer oils have the same oil source (from the Permian source rocks), and the upper-layer oils also have the same source (mainly from the Jurassic source rocks). In Chepaizi, the hydrocarbons stored in reservoirs originated mainly from Jurassic and Permian rocks. However, Cretaceous source rocks also have some contribution to oil-gas supply for oil pools. The oil-source division results based on nitrogen compounds (carbazoles) are completely identical with those by common geochemical indices, indicating that carbazoles are of importance in oil type division and oil-source correlation.
Masked Perception Thresholds of Low Frequency Tones under Background Noises and Their Estimation by Loudness Model
Authors: Subedi Jishnu K. , Yamaguchi Hiroki , Matsumoto Yasunao
Published: April 2010

This paper presents experimental measurements of masked thresholds of low frequency tones under background noises and application of loudness model to estimate the thresholds. The measurements of thresholds for tones at frequencies 20, 31.5, 40 and 50 Hz were conducted under three background noise conditions: one ambient noise and 60–100 Hz band-pass noises at two levels. The measurements were carried out in an uncontrolled environment in relatively quiet times. The perception thresholds of the same subjects were also measured for frequencies 31.5, 40 and 50 Hz inside a cabin with ambient noise levels well below the average hearing thresholds specified in ISO 389–7. Moore's loudness model has been used to estimate the masked thresholds. The estimated thresholds from the loudness model have been compared with the results obtained in the experiment. The results indicate that the noise above 50 Hz is effective in masking the low frequency tones at 50 Hz and below, and that Moore's loudness model can predict reasonably the average of the measured masked thresholds.
Effects of Infrasound on Changes of Intracellular Calcium Ion Concentration and on Expression of RyRs in Hippocampus of Rat Brain
Authors: Zhao-Hui Liu , Jing-Zao Chen , Yan Tang , Dan Chen , Gui-Rong Ding , Jing Li , Cheng Jin , Kang-Chu Li
Published: April 2010

In the present study, we investigated the molecular biological effect of infrasound on changes of intracellular free Ca2+ concentration ([Ca2+]i) and on expression of ryanodine receptors (RyRs) in the hippocampus of rats. 60 SD rats were randomized into ten groups and examined for [Ca2+]i and RyRs expression after exposure to 8Hz 90dB infrasound at days 1, 7, 14 and 21. Groups exposed to infrasound were exposed to 8Hz 90dB infrasound for 2 hours once daily. Acute cell separation, fluo-3/AM fluorescence technique and laser scanning confocal microscope (LSCM) were used for measurement of the [Ca2+]i level. There was no significant difference of [Ca2+]i at 1d and 7d infrasound exposure groups compared to control, but there was a significant incease at 14d group (P<0.01) and 21d group (P<0.05). Immunohistochemistry indicated the expression of RyRs in CA1 and CA3 pyramidal cells of the hippocampus showed no difference at 1d and 7d groups compared to control, whereas significant decrease was observed at 14d group (P<0.01) and 21d group (P<0.05). The data suggest that infrasound of 8Hz 90dB can induce [Ca2+]i increase and decrease the expression of RyRs in CA1 and CA3 regions of the hippocampus after exposure to infrasound for 14 and 21 days.
Optimal Placement of MR Dampers for Structural Control Using Identification Crossover Genetic Algorithm
Authors: Guo H. Y. , Zhang L.
Published: April 2010

In order to study the optimal placement of magnetorheological (MR) fluid dampers for structural control, an improved genetic algorithm, i.e. identification crossover genetic algorithm (ICGA), is presented in this paper. The method avoids the constraint violations caused by simple crossover and basic mutation operation. The ICGA produces an identification code. The crossover based on the identification code as well as mutation based on bit-by-bit basis guarantees the fulfillment of constraints. The analytical results by ICGA and general genetic algorithm are compared. It is concluded that the converging speed by ICGA is faster than the converging speed by general genetic algorithm and the control effect by optimal placement is satisfactory.
Nonlinear Dynamics of a Spur Gear Pair with Time-Varying Stiffness and Backlash
Authors: Yongjun Shen , Shaopu Yang , Cunzhi Pan , Xiandong Liu
Published: April 2010

In this paper the nonlinear dynamics of a spur gear pair are researched based on the Incremental Harmonic Balance Method (IHBM), where the time-varying stiffness and backlash are included. Firstly, the general forms of the periodic solutions are established. Then the frequency-response of this system is investigated by IHBM, and the effects of damping ratio and amplitude of excitation on the response are also analyzed. Based on the results presented in this paper the periodic solution with arbitrary precision can be expeditiously obtained, which is useful in analyzing or controlling the dynamics of the gear system. Finally some problems ignored in other references are pointed out.
The Solution of Low Frequency Noise Problems Associated with a Combined Heat and Power Plant
Authors: Marriott Ken , Leventhall Geoff
Published: April 2010

Complaints of low frequency noise arose following installation of a CHP system in an existing boiler room. Control was by a multi-stage process, the main phases of which were:

Reduction of LF noise in the boiler room: Detuning the stack: Reduction of breakout from the stack: Identifying the residual problem.

The final phase enabled the correct exhaust silencer to be selected.

The end result was that annoying excitation of room modes and irritating throbbing noises were reduced to below complaint level.
Continuous Pressure Waves Generated by a Train Running in a Tunnel
Authors: Kikuchi Katsuhiro , Ozawa Satoru , Takami Hajime , Iida Masanobu
Published: April 2010

This research describes several characteristics of tunnel continuous waves (TCW), which are a kind of low-frequency pressure wave radiated from railway tunnel portals. Several theoretical results are presented and measurement data obtained in field tests. Ratios of the amplitude and the frequency of the TCW radiated in the forward direction to those radiated backward have been obtained. Also described is a method for separating an incident wave from pressure data measured in a tunnel and this method is applied to data obtained in field tests. As a result, the separation method is shown to be applicable to the field test data.
Transverse Vibration Characteristics of a Paper Web with Multi-Roller Supports
Authors: Wu Jimei , Wang Zhongmin , Wu Qiumin , Wang Yan , Guo Xuxia
Published: April 2010

A transverse vibration model of a moving paper web is established by the rectangular mebrane theory. The differential equation of the moving paper web is established by considering constraint on the intermediate printing cylinders as an intermediate support, then the frequency equation is obtained by means of a Laplace transform. Finally, the relationships between vibration frequency and velocity, tension, rigidity modulus and support position of the moving paper web are analysed. The conclusions provide a theoretical basis and an effective approach for improving the structural design and working stability of the printing press.
Dual-Stage HDD Disturbance Cancellation based on an Efficient Adaptive Feedforward Compensation Algorithm
Authors: Zhang Hongbo , Huang Xinhan , Peng Gang , Wang Min
Published: April 2010

This paper applies an efficient adaptive feedforward compensation (AFC) algorithm for periodic disturbance cancellation on a hard disk drive (HDD) servo system. Such an algorithm is shown to be equivalent to a linear time invariant (LTI) model. With the help of this equivalence, we can easily choose optimal phase advance parameters, precisely predict the upper bounds of the allowable adaptation gains and determine the appropriate coefficients of a feedthrough term. Additionally, in order to obtain higher servo bandwidth, a dual-stage actuated structure is put forward. This dual-stage actuator system consists of a Voice Coil Motor (VCM) as a primary actuator and a micro actuator as a secondary actuator. Such a configuration can further reject the disturbance and maximize the servo system performance. The simulation results in time domain and frequency domain show that this scheme is capable of achieving a satisfactory performance in dealing with disturbances.
Low Frequency Noise. What we know, what we do not know, and what we would like to know
Authors: Leventhall Geoff
Published: April 2010

The paper reviews perception of low frequency noise (LFN) and the responses of people to LFN. Sometimes, when there are complaints of LFN and its effects, a specific noise cannot be measured. The possibilities are considered for development of enhanced sensitivity, for alternative (non-aural) receptors at very low frequencies and for false perceptions. The way in which we measure LFN may contribute to the problems.
On the Melting and Disordering of Thin Epitaxial Films
Authors: Patrykiejew A. , Sokolowski S.
Published: April 2010

The disordering of thin films formed on the (100) plane of the face centred cubic (fcc) crystal was studied by the Monte Carlo simulation method. It was shown that the adsorbed films, which order into the (1 × 1) structure in each layer at low temperatures, disorder in a layer-by-layer mode, at least for films with thicknesses of up to 12 layers. It was also demonstrated that, with increasing film thickness, the temperature at which the film disorders depended on the strain resulting from the mismatch between the sizes of the adsorbate atoms and the surface lattice.
Irreversible Adsorption of Particles on Surface Features of a Circular and Rectangular Shape
Authors: Adamczyk Zbigniew , Barbasz Jakub
Published: April 2010

The irreversible adsorption of spherical particles on surface features of various shapes (collectors) was studied using the Random Sequential Adsorption (RSA) model. Collectors in the form of circles and rectangles were considered, including the limiting cases of squares. Numerical simulation of the Monte Carlo type enabled the particle configurations to be determined, together with their density distribution (coverage) and the saturation coverage for various collectors to particle size ratio L̅ = L/2a and collector width to particle size ratio b̅ = b/2a. An unexpected feature found in these calculations was that the local coverage distribution of adsorbed particles was highly non-uniform, exhibiting a maximum at the centre and at the periphery of these collectors. The main finding of these calculations was the averaged number of particles  adsorbed at the saturation state on collectors as a function of the L̅ and b̅ parameters. It was revealed that  was highest for the square collector (for a fixed value of L̅). For L̅ > 5, our numerical results could be well approximated by the analytical expression  = Θ∞ L̅2 for circles,  = 4Θ∞ L̅2π for squares and  = Θ∞ b̅L̅2/π for rectangles. It was demonstrated that the theoretical results are in an agreement with experimental data obtained for latex particles adsorbed onto patterned surfaces obtained by a polymer-on-polymer stamping technique for gold-covered silicon and on photolithographically-patterned silane layers on silica.
Advanced Analysis of SEM Images of Carbon-Ceramic Composites
Authors: Rożniatowski Krzysztof , Kosmulski Marek
Published: April 2010

Carbon deposits obtained by the pyrolysis of cyclohexene and of glucose in the pores of porous monoliths of alumina and Y-modified zirconia consist of randomly distributed insulated islands. This explains their relatively low electric conductance. A tesselation method was applied to quantify the distribution of carbon deposits in the ceramic matrix.
The Structural Properties and Diffusion of a Three-Dimensional Isotropic Core-Softened Model Fluid in Disordered Porous Media. Molecular Dynamics Simulation
Authors: Dominguez Hector , Pizio Orest , Pusztai Laszlo , Sokolowski Stefan
Published: April 2010

The microscopic structure and dynamic properties of an isotropic three-dimensional core-softened model fluid in disordered matrices of Lennard-Jones particles have been studied. Molecular dynamics computer simulations in Grand Canonical ensemble were used as the methodological tools. It was shown that the microscopic structure of the fluid is characterized by anomalies similar to those found in a bulk model, but that it is affected by the fluid-matrix interactions. The dynamic properties also exhibit anomalous dependence on fluid density, but the magnitude of these anomalies is suppressed in comparison to the bulk fluid model. The anomalous behaviour of the diffusion coefficient is attributed to structural changes in the first coordination shell of a given fluid particle. It seems that the anomalies can only be suppressed at matrix densities which are higher than those studied in the present work.
Analysis of Binary Adsorption Excess Isotherms at the Liquid/Solid Interface
Authors: Kalies Grit , Bräuer Peter , Rockmann Rico
Published: April 2010

Adsorption excesses of binary liquid mixtures are the primary experimental quantity in liquid-phase adsorption onto porous or disperse solids. Binary liquid adsorption isotherms can be easily measured and allow statements to be made about the characteristics of solid and liquid mixtures, immersion behaviour at the liquid/solid interface, multi-component adsorption, etc. In this paper, a brief summary is given of different ways of interpreting and analysing binary isotherms over the whole concentration range. Experimental data and calculation examples show that thermodynamics provides a powerful tool for obtaining relevant information from such isotherms.
Heterogeneities in Adsorption from Aqueous Solution — An Example of the Effect of Surface Coverage
Authors: Lützenkirchen Johannes , Huber Florian
Published: April 2010

Studies of the interaction of uranyl species with the surface of quartz are reported. Two approaches were applied. These were (i) the classical static batch adsorption approach in which only the forward adsorption uptake reaction is usually studied and (ii) a dynamic column approach in which the retention of a solute during its migration through a porous medium is investigated and where adsorption and desorption are both relevant for the final breakthrough curve.

In this paper, we present the results of a column study at pH 4. Under these conditions, the interference of the carbonate ion (via the formation of dissolved or adsorbed uranyl-carbonato species), the effects of quartz surface charge (quartz/silica is virtually uncharged under these conditions) and the potential effects of quartz dissolution on uranyl speciation (via the formation of dissolved or adsorbed uranyl-silicato species) are minimised. The reported batch adsorption results are reasonably predicted by a model which under similar conditions successfully described batch and column data on a quartz sample with grains smaller than the quartz particles used in the present study by a factor of ca. 25. However, this model was incapable of describing the breakthrough behaviour of uranyl species. This failure was attributed to the heterogeneity of the quartz particles used, which may be more important for column breakthrough than for batch adsorption data.