Micromagnetic Simulations of Anisotropies in Coupled and Uncoupled Ferromagnetic Nanowire Systems

The influence of a variation of spatial relative orientations onto the coupling dynamics and subsequent magnetic anisotropies was modeled in ferromagnetic nanowires. The wires were analyzed in the most elementary configurations, thus, arranged in pairs perpendicular to each other, leading to one-dimensional (linear) and zero-dimensional (point-like) coupling. Different distances within each elementary pair of wires and between the pairs give rise to varying interactions between parallel and perpendicular wires, respectively. Simulated coercivities show an exchange of easy and hard axes for systems with different couplings. Additionally, two of the systems exhibit a unique switching behavior which can be utilized for developing new functionalities

Pojava i određivanje Thermoanaerobacterium i Thermoanaerobacter u konzerviranoj hrani u limenkama

In order to determine the reason for loss of vacuum in canned food, obligately anaerobic, spore forming thermophilic organisms were isolated from shelf-stable canned food containing vegetables, noodles and potatoes as main ingredients. Thermophilic bacteria from 44 canned food samples that had been stored under anaerobic conditions at 37 °C for at least 7 days were isolated. In addition, organic fertilizer used for the cultivation of some of the foods’ ingredients was examined and anaerobic, thermophilic bacteria could also be isolated from this source. Identification of bacterial strains was carried out by partial and complete 16S-rRNA-gene sequencing. Some of the obtained gene sequences showed a high level of similarity to existing 16S-rRNA gene sequences towards strains of the genera Thermoanaerobacter, Thermoanaerobium and Thermoanaerobacterium respectively, which have not yet been reported to be of importance as food spoilers. In the course of identification of these thermophilic bacteria we developed genera specific PCR-based approaches for detecting isolates belonging to the genera Thermoanaeroacterium and Thermoanaerobacter. Direct capturing of free DNA from contaminated samples using oligonucleotides coupled with paramagentic beads allowed the reduction of the detection time to six hours with a lower limit of 104 cells/mL.Da bi se odredio uzrok nestanka vakuuma u limenkama konzervirane hrane, obligatni anaerobi, termofilni organizmi koji stvaraju spore, izolirani su iz hrane u limenkama s glavnim sastojcima: povrće, rezanci i krumpir. Izolirane su termofilne bakterije iz 44 uzorka limenki uskladištenih pod anaerobnim uvjetima pri 37 °C barem 7 dana. Osim toga, ispitana su organska gnojiva upotrijebljena za uzgoj navedenog povrća pa su i iz tog izvora izolirane anaerobne termofilne bakterije. Identifikacija bakterijskih sojeva provedena je djelomičnim i potpunim sekvencioniranjem 16S-rRNA gena. Neke od dobivenih genskih sekvencija pokazale su visoki stupanj sličnosti s postojećim sekvencijama 16S-rRNA gena sojeva rodova Thermoanaerobacter, Thermoanaerobium i Thermoanaerobacterium. Do sada još nije bila ustanovljena važnost tih sojeva kao onečišćavača hrane. Tijekom identifikacije navedenih termofilnih bakterija autori su razvili genetički specifičan pristup utemeljen na PCR za određivanje izolata koji pripadaju rodovima Thermoanaerobacterium i Thermoanaerobacter. Izravno vezanje slobodne DNA iz onečišćenih uzoraka, koristeći oligonukleotide povezane s paramagnetskim zrncima omogućilo je smanjenje vremena detekcije na 6 sati s donjom granicom od 104 stanica/mL

Optical differentiation between cashmere and other textile fibres by laser diffraction

This paper reports a novel method to differentiate cashmere from synthetic fibres and even from other wool fibres with the help of laser diffraction patterns. In the diffraction pattern, only natural fibres depict additional spots above and below the actual diffraction plane. These spots can be used to distinguish different fibre materials by comparing their length-to-height aspect ratio with standard values. Especially, it can be recognized that the diffraction lines above and below the diffraction plane are significantly longer and finer for cashmere fibres than for any other wool

SxsA, a novel surface protein mediating cell aggregation and adhesive biofilm formation of Staphylococcus xylosus

Biofilm formation of staphylococci has been an emerging field of research for many years. However, the underlying molecular mechanisms are still not fully understood and vary widely between species and strains. The aim of this study was to identify new effectors impacting biofilm formation of two Staphylococcus xylosus strains. We identified a novel surface protein conferring cell aggregation, adherence to abiotic surfaces, and biofilm formation. The S. xylosus surface protein A (SxsA) is a large protein occurring in variable sizes. It lacks sequence similarity to other staphylococcal surface proteins but shows similar structural domain organization and functional features. Upon deletion of sxsA, adherence of S. xylosus strain TMW 2.1523 to abiotic surfaces was completely abolished and significantly reduced in TMW 2.1023. Macro- and microscopic aggregation assays further showed that TMW 2.1523 sxsA mutants exhibit reduced cell aggregation compared with the wildtype. Comparative genomic analysis revealed that sxsA is part of the core genome of S. xylosus, Staphylococcus paraxylosus, and Staphylococcus nepalensis and additionally encoded in a small group of Staphylococcus cohnii and Staphylococcus saprophyticus strains. This study provides insights into protein-mediated biofilm formation of S. xylosus and identifies a new cell wall-associated protein influencing cell aggregation and biofilm formation.Peer Reviewe

Wavelength Orthogonal Photodynamic Networks

The ability of light to remotely control the properties of soft matter materials in a dynamic fashion has fascinated material scientists and photochemists for decades. However, only recently has our ability to map photochemical reactivity in a finely wavelength resolved fashion allowed for different colors of light to independently control the material properties of polymer networks with high precision, driven by monochromatic irradiation enabling orthogonal reaction control. The current concept article highlights the progress in visible light-induced photochemistry and explores how it has enabled the design of polymer networks with dynamically adjustable properties. We will explore current applications ranging from dynamic hydrogel design to the light-driven adaptation of 3D printed structures on the macro- and micro-scale. While the alternation of mechanical properties via remote control is largely reality for soft matter materials, we herein propose the next frontiers for adaptive properties, including remote switching between conductive and non-conductive properties, hydrophobic and hydrophilic surfaces, fluorescent or non-fluorescent, and cell adhesive vs. cell repellent properties

Effect of High Pressure and Heat on Bacterial Toxins

Even though the inactivation of microorganisms by high pressure treatment is a subject of intense investigations, the effect of high pressure on bacterial toxins has not been studied so far. In this study, the influence of combined pressure/temperature treatment (0.1 to 800 MPa and 5 to 121 °C) on bacterial enterotoxins was determined. Therefore, heat-stable enterotoxin (STa) of cholera toxin (CT) from Vibrio cholerae, staphylococcal enterotoxins A-E, haemolysin BL (HBL) from Bacillus cereus, and Escherichia coli (STa) were subjected to different treatment schemes. Structural alterations were monitored in enzyme immunoassays (EIAs). Cytotoxicity of the pressure treated supernatant of toxigenic B. cereus DSM 4384 was investigated with Vero cells. High pressure of 200 to 800 MPa at 5 °C leads to a slight increase of the reactivity of the STa of E. coli. However, reactivity decreased at 800 MPa and 80 °C to (66±21) % after 30 min and to (44±0.3) % after 128 min. At ambient pressure no decrease in EIA reactivity could be observed after 128 min. Pressurization (0.1 to 800 MPa) of heat stable monomeric staphylococcal toxins at 5 and 20 °C showed no effect. A combined heat (80 °C) and pressure (0.1 to 800 MPa) treatment lead to a decrease in the immuno-reactivity to 20 % of its maximum. For cholera toxin a significant loss in latex agglutination was observable only at 80 °C and 800 MPa for holding times higher than 20 min. Interestingly, the immuno-reactivity of B. cereus HBL toxin increased with the increase of pressure (182 % at 800 MPa, 30 °C), and high pressure showed only minor effects on cytotoxicity to Vero cells. Our results indicate that pressurization can increase inactivation observed by heat treatment, and combined treatments may be effective at lower temperatures and/or shorter incubation time

High energy gamma ray balloon instrument

The High Energy Gamma Ray Balloon Instrument was built in part to verify certain subsystems' performance for the Energetic Gamma Ray Experiment Telescope (EGRET) instrument, the high energy telescope to be carried on the Gamma Ray Observatory. This paper describes the instrument, the performance of some subsystems, and some relevant results

Effect of High Pressure and Heat on Bacterial Toxins

Even though the inactivation of microorganisms by high pressure treatment is a subject of intense investigations, the effect of high pressure on bacterial toxins has not been studied so far. In this study, the influence of combined pressure/temperature treatment (0.1 to 800 MPa and 5 to 121 °C) on bacterial enterotoxins was determined. Therefore, heat-stable enterotoxin (STa) of cholera toxin (CT) from Vibrio cholerae, staphylococcal enterotoxins A-E, haemolysin BL (HBL) from Bacillus cereus, and Escherichia coli (STa) were subjected to different treatment schemes. Structural alterations were monitored in enzyme immunoassays (EIAs). Cytotoxicity of the pressure treated supernatant of toxigenic B. cereus DSM 4384 was investigated with Vero cells. High pressure of 200 to 800 MPa at 5 °C leads to a slight increase of the reactivity of the STa of E. coli. However, reactivity decreased at 800 MPa and 80 °C to (66±21) % after 30 min and to (44±0.3) % after 128 min. At ambient pressure no decrease in EIA reactivity could be observed after 128 min. Pressurization (0.1 to 800 MPa) of heat stable monomeric staphylococcal toxins at 5 and 20 °C showed no effect. A combined heat (80 °C) and pressure (0.1 to 800 MPa) treatment lead to a decrease in the immuno-reactivity to 20 % of its maximum. For cholera toxin a significant loss in latex agglutination was observable only at 80 °C and 800 MPa for holding times higher than 20 min. Interestingly, the immuno-reactivity of B. cereus HBL toxin increased with the increase of pressure (182 % at 800 MPa, 30 °C), and high pressure showed only minor effects on cytotoxicity to Vero cells. Our results indicate that pressurization can increase inactivation observed by heat treatment, and combined treatments may be effective at lower temperatures and/or shorter incubation time

Obesity and insulin sensitivity effects on cardiovascular risk factors: Comparisons of obese dysglycemic youth and adults

Background: Obesity and pubertal insulin resistance worsen cardiovascular (CV) risk factors in youth. It is unclear how the relationships of obesity and insulin resistance with CV risk compare to adults. Subjects and Methods: We evaluated 66 pubertal youth (mean ± SD: age 14.2 ± 2.0 years, body mass index [BMI] 36.6 ± 6.0 kg/m2, hemoglobin A1c [HbA1c] 38.5 ± 6.1 mmol/mol) and 355 adults with comparable BMI (age 52.7 ± 9.4 years, BMI 35.1 ± 5.1 kg/m2, HbA1c 39.8 ± 4.2 mmol/mol) participating in a multicenter study. Insulin sensitivity was quantified using hyperglycemic clamps. Assessment of CV risk factors was standardized across sites. Regression analyses compared the impact of insulin sensitivity and CV risk factors between youth and adults. Results: Obese pubertal youth were more insulin resistant than comparably obese adults (P \u3c.001), but with similar slopes for the inverse relationship between insulin sensitivity and obesity. The impact of obesity on CV risk factors was explained by insulin sensitivity (P = NS after adjustment for sensitivity). The two age groups did not differ in relationships between insulin sensitivity and diastolic blood pressure, total cholesterol, and low-density lipoprotein (LDL) cholesterol, after adjusting for obesity. However, while systolic blood pressure (SBP) and high-density lipoprotein (HDL) cholesterol exhibited the expected direct and inverse relationships, respectively with insulin sensitivity in adults, these slopes were flat in youth across the range of insulin sensitivity (P ≤.05 for group differences). Conclusions: Effects of obesity on CV risk factors were attributable to insulin sensitivity in both groups. The relationships between insulin sensitivity and CV risk factors were similar in obese youth and adult groups except for SBP and HDL cholesterol. Clinical Trial Registration: The RISE consortium studies are registered through Clinicaltrials.gov as NCT01779362 (Adult Medication Study); NCT01763346 (Adult Surgery Study); and NCT01779375 (Pediatric Medication Study). Clinical trial registration numbers: NCT01779362, NCT01779375 and NCT01763346 at clinicaltrials.gov