A comparison of methods for the determination of dissolved oxygen in seawater

An intercalibration of dissolved oxygen methods was conducted at 2 stations in the Sargasso Sea between April 28 and May 3, 1990. The experiment compared three techniques using automated endpoint detection with the manual Winkler method using a starch endpoint. Institutions participating in the intercomparison were the Bedford Institute of Oceanography (automated photometric titration), the University of Delaware (automated amperometric titration), the Scripps Institution of Oceanography (manual titration), and the Woods Hole Oceanographic Institution (automated amperometric titration). Differences in measured oxygen concentrations between institutions were encouragingly small. However, small, systematic differences in dissolved oxygen between institutions did exist. The range between the highest and lowest oxygen values reported by the 4 institutions never exceeded 0.6% over the entire concentration range studied (3.4 to 6.2 mlj1). The good agreement is probably due to the use of the essentials of Carpenter's (1965) modification of the Winkler method by all institutions. The intercalibration revealed several aspects of dissolved oxygen measurements that require further research: (1) the intercalibration should be extended to very low oxygen concentrations; (2) procedures for measur ing and applying corrections for the seawater blank need to be formalized; (3) a simple procedure to measure the temperature of seawater at the time of sampling needs to be developed; and (4) the solubility of atmospheric oxygen in the Winkler reagents must be measured as a function of temperature. The intercalibration also revealed that analytical techniques required for precise and accurate volumetric measurements were often not applied, even by experienced analysts. It was found that uncalibrated pipets were used to dispense standards, that the volumes of oxygen flasks were not corrected for buoyancy, and that corrections for the thermal expansion of aqueous solutions were often not applied.This research was supported by National Science Foundation Grants OCE 88- 22542 and OCE 88-21977 and OCE 89-07815. Preparation and distribution of this report by the WHP Office, Woods Hole Oceanographic Institution, Woods Hole, MA. 02543 USA, was supported by NSF Grant OCE 89-07815

Cloning, Expression, and Characterization of Thermotolerant Manganese Superoxide Dismutase from Bacillus sp. MHS47

A superoxide dismutase gene from thermotolerant Bacillus sp. MHS47 (MnSOD47) was cloned, sequenced, and expressed. The gene has an open reading frame of 612 bp, corresponding to 203 deduced amino acids, with high homology to the amino acid sequences of B. thuringiensis (accession no. EEN01322), B. anthracis (accession no. NP_846724), B. cereus (accession no. ZP_04187911), B. weihenstephanensis (accession no. YP_001646918), and B. pseudomycoides. The conserved manganese-binding sites (H28, H83, D165, and H169) show that MnSOD47 has the specific characteristics of the manganese superoxide dismutase (MnSOD) enzymes. MnSOD47 expressed an enzyme with a molecular weight of approximately 22.65 kDa and a specific activity of 3537.75 U/mg. The enzyme is active in the pH range 7–8.5, with an optimum pH of 7.5, and at temperatures in the range 30–45 °C, with an optimum temperature of 37 °C. Tests of inhibitors and metal ions indicated that the enzyme activity is inhibited by sodium azide, but not by hydrogen peroxide or potassium cyanide. These data should benefit future studies of MnSODs in other microorganisms and the biotechnological production of MnSOD47, and could also be used to develop a biosensor for the detection of antioxidants and free radical activity. In the future, this basic knowledge could be applicable to the detection of cancer risks in humans and therapeutic treatments

Percutaneous Cryoablation for the Treatment of Medically Inoperable Stage I Non-Small Cell Lung Cancer

BACKGROUND: To evaluate the midterm results of percutaneous cryoablation for medically inoperable stage I non-small cell lung cancer. METHODOLOGY/PRINCIPAL FINDINGS: Between January 2004 and June 2010, 160 patients underwent computer tomography guided percutaneous cryoablation for lung tumors at our institution. Of these patients, histologically proven stage I lung cancer patients with more than one year of follow-up, were retrospectively reviewed. All of these patients were considered to be medically inoperable with Charlson comorbidity index of 3 or greater. Follow-up was based primarily on computed tomography. There were 22 patients with 34 tumors who underwent 25 sessions of cryoablation treatment. Complications were pneumothoraces in 7 treatments (28%, chest tube required in one treatment), and pleural effusions in 8 treatments (31%). The observation period ranged from 12-68 months, average 29±19 months, median 23 months. Local tumor progression was observed in one tumor (3%). Mean local tumor progression-free interval was 69±2 months. One patient died of lung cancer progression at 68 months. Two patients died of acute exacerbations of idiopathic pulmonary fibrosis which were not considered to be directly associated with cryoablation, at 12 and 18 months, respectively. The overall 2- and 3-year survivals were 88% and 88%, respectively. Mean overall survival was 62±4 months. Median overall survival was 68 months. The disease-free 2- and 3-year survivals were 78% and 67%, respectively. Mean disease-free survival was 46±6 months. Pulmonary function tests were done in 16 patients (18 treatments) before and after cryoablation. Percentage of predicted vital capacity, and percentage of predicted forced expiratory volume in 1 second, did not differ significantly before and after cryoablation (93±23 versus 90±21, and 70±11 versus 70±12, respectively). CONCLUSIONS/SIGNIFICANCE: Although further accumulation of data is necessary regarding efficacy, cryoablation may be a feasible option in medically inoperable stage I lung cancer patients

HP1 Recruits Activity-Dependent Neuroprotective Protein to H3K9me3 Marked Pericentromeric Heterochromatin for Silencing of Major Satellite Repeats

H3 lysine 9 trimethylation (H3K9me3) is a histone posttranslational modification (PTM) that has emerged as hallmark of pericentromeric heterochromatin. This constitutive chromatin domain is composed of repetitive DNA elements, whose transcription is differentially regulated. Mammalian cells contain three HP1 proteins, HP1α, HP1β and HP1γ These have been shown to bind to H3K9me3 and are thought to mediate the effects of this histone PTM. However, the mechanisms of HP1 chromatin regulation and the exact functional role at pericentromeric heterochromatin are still unclear. Here, we identify activity-dependent neuroprotective protein (ADNP) as an H3K9me3 associated factor. We show that ADNP does not bind H3K9me3 directly, but that interaction is mediated by all three HP1 isoforms in vitro. However, in cells ADNP localization to areas of pericentromeric heterochromatin is only dependent on HP1α and HP1β. Besides a PGVLL sequence patch we uncovered an ARKS motif within the ADNP homeodomain involved in HP1 dependent H3K9me3 association and localization to pericentromeric heterochromatin. While knockdown of ADNP had no effect on HP1 distribution and heterochromatic histone and DNA modifications, we found ADNP silencing major satellite repeats. Our results identify a novel factor in the translation of H3K9me3 at pericentromeric heterochromatin that regulates transcription

Radiofrequency ablation of lung tumours

Pulmonary radiofrequency ablation (RFA) has become an increasingly adopted treatment option for primary and metastatic lung tumours. It is mainly performed in patients with unresectable or medically inoperable lung neoplasms. The immediate technical success rate is over 95%, with a low periprocedural mortality rate and 8–12% major complication rate. Pneumothorax represents the most frequent complication, but requires a chest tube drain in less than 10% of cases. Sustained complete tumour response has been reported in 85–90% of target lesions. Lesion size represents the most important risk factor for local recurrence. Survival data are still scarce, but initial results are very promising. In patients with stage I non-small-cell lung cancer, 1- and 2-year survival rates are within the ranges of 78–95% and 57–84%, respectively, with corresponding cancer-specific survival rates of 92% and 73%. In selected cases, the combination of RFA and radiotherapy could improve these results. In patients with colorectal lung metastasis, initial studies have reported survival data that compare favourably with the results of metastasectomy, with up to a 45% 5-year survival rate. Further studies are needed to understand the potential role of RFA as a palliative treatment in more advanced disease and the possible combination of RFA with other treatment options

Measuring the Entrepreneurial Mindset: The Motivations behind the Behavioral Intentions of Starting a Sustainable Business

The aim of this study was to investigate the entrepreneurial mindset that underlies the behavioral intentions of starting a sustainable business. The research was driven by the factors that are the key drivers of the economy through fostering growth, job creation, technology adoption, and innovation, as well as poverty alleviation. The research adopted a descriptive research design, with the primary data collected from those respondents with at least two years of sustainable business experience. The model comprised entrepreneurial education, innovativeness, and risk-taking as the independent variables, creativity as a mediating variable, and entrepreneurial intention as the dependent variable. The research adopted structural equation modeling to analyze the research objective and verify the hypothesis. The findings indicate that entrepreneurial education, innovativeness, and creativity significantly and positively influence entrepreneurs’ intention to start a sustainable business. Creativity was found to be influenced significantly and positively by entrepreneurial education, risk-taking, innovativeness, and creativity. The research recommends that to enhance the entrepreneurial mindset and the intention to start a sustainable business, the factors that should be enhanced are entrepreneurial education, innovativeness, and creativity. Innovation leads to the development of new products and services in the market; entrepreneurship education equips a person with entrepreneurship fundamentals, while creativity fosters the progress of a sustainable business toward achieving its objectives

Movement of an submerged body in conditions of shallow water depth

Forces and moments acting on an AUV during its movement play a decisive role in its manoeuvrability and operational parameters. When choosing the shape of a vehicle, it is necessary to provide for obtaining acceptable hydrodynamic qualities that ensure the vital activity of a crew and the placement of equipment, which directly affects the dimensions and external outlines of an AUV. The purpose of the study was to determine the performance of the numerical model in the ANSYS software by comparing the results of the hydrodynamic characteristics of the object with experimental data and data from other studies. Hydrodynamic forces acted on the immersed body from the side of the liquid at a small immersion depth. The dependences demonstrated both qualitative and quantitative agreement between the experimental and numerical results. In general, we concluded that the proposed methodology and method of conducting model experiments and the numerical algorithm developed by us, accurately describes the process of motion of a submerged body in a near-surface water environment

Assessing the Influence of Collaborative Technology Adoption—Mediating Role of Sociotechnical, Organizational, and Economic Factors

The study investigated the factors that influence the adoption of collaborative robots in the manufacturing sector in Russia from sociotechnical, organizational, and economic point of views. The study was driven by the increasing technological innovation in the manufacturing sector, especially in the use of robots and collaborative robot applications in daily manufacturing, flexibility, and operations activities. The study was a quantitative, descriptive survey that relied on primary data from respondents with varied experiences in the manufacturing sector in Russia. The study employed a total of 351 respondents selected for their insights into the application of robotics in the manufacturing process in Russia. The model adopted for the study was tested using confirmatory factor analysis (CFA), reliability, and validity analysis. The hypotheses of the study were evaluated using partial least-squares analysis. The results revealed that the adoption of collaborative robots was influenced by organizational factors and economic factors. Perceived performance improvement was significantly influenced by collaborative robot adoption and sociotechnical systems. The study recommended that the stakeholders in Russia’s manufacturing sector should improve their training, management support, perceived innovativeness, and prior experience to enhance the adoption of collaborative robots and flexibility in design