scholarly journals Low-Temperature Growth of Shewanella oneidensis MR-1

2005 ◽  
Vol 71 (2) ◽  
pp. 811-816 ◽  
Author(s):  
Randa Abboud ◽  
Radu Popa ◽  
Virginia Souza-Egipsy ◽  
Carol S. Giometti ◽  
Sandra Tollaksen ◽  
...  
Keyword(s):  
Room Temperature ◽  
Doubling Time ◽  
Shewanella Oneidensis ◽  
Maximum Growth ◽  
Lag Phase ◽  
Temperature Growth ◽  
Wide Range ◽  
Mesophilic Bacterium ◽  
Cellular Lipids ◽  
Higher Temperature

ABSTRACT Shewanella oneidensis MR-1 is a mesophilic bacterium with a maximum growth temperature of ≈35°C but the ability to grow over a wide range of temperatures, including temperatures near zero. At room temperature (≈22°C) MR-1 grows with a doubling time of about 40 min, but when moved from 22°C to 3°C, MR-1 cells display a very long lag phase of more than 100 h followed by very slow growth, with a doubling time of ≈67 h. In comparison to cells grown at 22°C, the cold-grown cells formed long, motile filaments, showed many spheroplast-like structures, produced an array of proteins not seen at higher temperature, and synthesized a different pattern of cellular lipids. Frequent pilus-like structures were observed during the transition from 3 to 22°C.

scholarly journals Key properties of inorganic thermoelectric materials – tables (version 1)

2022 ◽  
Author(s):  
Robert Freer ◽  
Dursun Ekren ◽  
Tanmoy Ghosh ◽  
Kanishka Biswas ◽  
Pengfei Qiu ◽  
...  
Keyword(s):  
Thermoelectric Properties ◽  
Conversion Efficiency ◽  
Thermoelectric Materials ◽  
Room Temperature ◽  
Temperature Data ◽  
Inorganic Materials ◽  
Peak Performance ◽  
Thermoelectric Conversion ◽  
Wide Range ◽  
Higher Temperature

Abstract This paper presents tables of key thermoelectric properties, which define thermoelectric conversion efficiency, for a wide range of inorganic materials. The 12 families of materials included in these tables are primarily selected on the basis of well established, internationally-recognised performance and their promise for current and future applications: Tellurides, Skutterudites, Half Heuslers, Zintls, Mg-Sb Antimonides, Clathrates, FeGa3–type materials, Actinides and Lanthanides, Oxides, Sulfides, Selenides, Silicides, Borides and Carbides. As thermoelectric properties vary with temperature, data are presented at room temperature to enable ready comparison, and also at a higher temperature appropriate to peak performance. An individual table of data and commentary are provided for each family of materials plus source references for all the data.

Comparison of Enrichment Broths for the Recovery of Healthy and Heat-Injured Salmonella Typhimurium on Raw Duck Wings

2013 ◽  
Vol 76 (11) ◽  
pp. 1963-1968 ◽  
Author(s):  
QIANWANG ZHENG ◽  
CAROLINE BUSTANDI ◽  
YISHAN YANG ◽  
KEITH R. SCHNEIDER ◽  
HYUN-GYUN YUK
Keyword(s):  
Growth Rate ◽  
Salmonella Typhimurium ◽  
Doubling Time ◽  
Growth Parameters ◽  
False Negative ◽  
Maximum Growth ◽  
Maximum Growth Rate ◽  
Detection Methods ◽  
Lag Phase ◽  
Peptone Water

This study was performed to optimize Salmonella Typhimurium recovery from raw duck wings with five nonselective broths (buffered peptone water, tryptic soy broth, lactose broth, universal preenrichment broth, nutrient broth) and four selective broths (selenite broth, BAX System MP media [MP], Salmonella AD media [AD], ONE broth-Salmonella [OB]). Healthy or heat-injured (50 and 85% injury) cells were inoculated at a level of 102, 101, or 100 CFU/25 g on raw duck wings. Growth was modeled using DMfit with four growth parameters: lag-phase duration, maximum growth rate, doubling time, and maximum population density. Most enrichments were able to recover Salmonella Typhimurium to greater than 6 log CFU/ml. AD, MP, and OB had significantly (P < 0.05) higher maximum growth rate (0.9 to 1.0/h) and lower doubling time (0.7 to 0.8 h). Buffered peptone water, AD, MP, and OB recovered healthy and 50%-injured cells at low inoculum levels to more than 6.0 log CFU/ml; OB achieved the greatest recovery (7.6 and 7.9 log CFU/ml), following 24 h of incubation. The 85%-injured cells at 100 and 101 CFU/25 g, however, were only recovered in OB, reaching 7.3 and 7.5 log CFU/ml, respectively. These results suggest that OB may be an appropriate enrichment broth for the recovery of Salmonella Typhimurium from raw duck wings in standard diagnostic tests or other rapid detection methods, to avoid false-negative results.

The Effect of Physical Conditions on the Transportation of Peripheral Blood Progenitor (PBPC) Products.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 2315-2315
Author(s):  
Jan Jansen ◽  
Pamela L Nolan ◽  
Margaret I Reeves ◽  
Luke Paul Akard ◽  
James M. Thompson ◽  
...  
Keyword(s):  
Trypan Blue ◽  
Room Temperature ◽  
Trypan Blue Exclusion ◽  
Physical Conditions ◽  
Cd34 Cells ◽  
Wide Range ◽  
Duration Of Storage ◽  
Higher Temperature ◽  
Storage Times ◽  
And Storage

Abstract The viability of transported PBPC products has not been studied extensively. Commonly, PBPC products are transported at a concentration of >200 x109/l in containers with −20oC ice packs. Continuous temperature monitoring has shown that the temperatures of these products stays at <10oC for less than 24 hours and reaches room temperature by 48 hours. Samples of freshly collected PBPC from 12 allogeneic donors were studied for various viability parameters during storage for up to 96 hours. The effects of storage time, concentration of cells, temperature, and storage in gas-permeable bags were studied. Trypan-blue exclusion and double fluorescence for 7-AAD and CD34 were used for viability assessment. Over a wide range of temperatures and storage times, the viable CD34+ assay was more sensitive to damage than trypan-blue exclusion (mean Δ 10.7%, p<0.0001 in paired t-test). The viable CD34+ assay was routinely used in parallel with CFU-GM cultures. No difference in survival of viable CD34+ cells or CFU-GM was found whether cells were incubated for 48hr in test-tubes or in gas-permeable bags. When cells at 200 x 109/l were incubated for 48hr at room temperature, the mean viability decreased to 19% and 6% of starting values of viable CD34+ cells and CFU-GM, respectively. Serial dilution to 25 x 109/l improved the survival to 81% and 51% respectively. Similarly, incubation at lower temperatures led to better survival of CD34+ cells and CFU-GM: 67% and 18% at 17oC, 80% and 50% at 13oC, and 95% and 86% at 4oC. At 200 x109/l and 22oC the survivals of CD34+ cells and CFU-GM were 74% and 21% at 24hr, 19% and 7% at 48hr, 7% and 6% at 72hr, and 3% and 13% at 96hr. The effects of concentration, temperature and duration of storage were all significant (p<0.05). Transportation at 4oC leads to the best survival of CD34+ cells and CFU-GM, in particular at a low concentration. If transportation at a slightly higher temperature is necessary, dilution of the PBPC product will enhance the survival of CD34+ cells and CFU-GM. Proliferative assays such as CFU-GM appear the most sensitive parameters of PBPC survival, and should be included in the validation process of PBPC transportation.

Growth of Heat-Treated Enterotoxin-PositiveClostridium perfringens and the Implications for Safe Cooling Rates

2004 ◽  
Vol 67 (1) ◽  
pp. 83-89 ◽  
Author(s):  
KARIN G. ANDERSEN ◽  
TINA B. HANSEN ◽  
SUSANNE KNØCHEL
Keyword(s):  
Clostridium Perfringens ◽  
Spore Germination ◽  
Generation Time ◽  
Growth Characteristics ◽  
Heat Inactivation ◽  
Lag Phase ◽  
Temperature Growth ◽  
Generation Times ◽  
Heat Treated ◽  
Higher Temperature

Clostridium perfringens 790-94 and 44071.C05 carrying a chromosomal and a plasmid cpe gene, respectively, were used to determine differences in heat resistance and growth characteristics between the genotypes. Heat inactivation experiments were conducted using an immersed coil apparatus. Spore germination, outgrowth, and lag phase, together named GOL time, as well as generation times were determined during constant temperatures in fluid thioglycollate (FTG) medium as well as in vacuum-packed, heat-treated minced turkey. GOL time and growth were also monitored during cooling scenarios from 65 to 10°C for 3, 4, 5, 6, and 7 h in vacuum-packed, heat-treated minced turkey. Spores of strain 790-94 were approximately 10-fold more heat resistant at 85°C than those of strain 44071.C05, and strain 790-94 also had a higher temperature growth range in FTG. The higher growth range for a chromosomal enterotoxin-producing CPE+ strain was confirmed using two other strains carrying a chromosomal (NCTC8239) and plasmid (945P) cpe gene. Moreover, strain 790-94 had shorter GOL times at 50°C in turkey and approximately half the generation time compared with strain 44071.C05 at temperatures ≥45°C in both FTG and turkey. Strain 790-94 increased with 0.3, 1.0, 1.7, and 2.0 logs, respectively, during cooling from 65 to 10°C in 4, 5, 6, and 7 h, which was signi cantly higher than for strain 44071.C05. A maximum acceptable cooling time of 5 h between 65 and 10°C is suggested.

scholarly journals Growth in catheter biofilms and antibiotic resistance of Mycobacterium avium

2007 ◽  
Vol 56 (2) ◽  
pp. 250-254 ◽  
Author(s):  
Joseph O. Falkinham
Keyword(s):  
Antibiotic Resistance ◽  
Mycobacterium Avium ◽  
Growth Rates ◽  
Nutrient Concentration ◽  
Room Temperature ◽  
Doubling Time ◽  
Temperature Growth ◽  
Initial Cell ◽  
Cell Densities ◽  
Catheter Tubing

Cells of Mycobacterium avium strain A5 adhered to plasticized polyvinyl chloride catheter tubing and grew at low nutrient concentration, consistent with reports of catheter-associated M. avium infection. Starting with initial cell densities of 1–2×106 c.f.u. ml−1, biofilms of approximately 350 c.f.u. cm−2 formed within 24 h at room temperature. Growth rates of cells in biofilms were exponential and equal to 2.45 days doubling time. Rates were exponential for 1–2 weeks incubation and reached cell densities of 6.5×104 c.f.u. cm−2 by 4 weeks. Cells grown in catheter biofilms were significantly more resistant to clarithromycin and rifamycin than cells grown in suspension.

Growth of au on a ge (111) surface

1992 ◽  
Vol 50 (2) ◽  
pp. 1434-1435
Author(s):  
D.N. Dunn ◽  
P. Xu ◽  
L.D. Marks
Keyword(s):  
Growth Mechanism ◽  
Noble Metals ◽  
Room Temperature ◽  
Annealing Temperature ◽  
Two Dimensional ◽  
Temperature Growth ◽  
Wide Range ◽  
Device Applications

The growth of noble metals such as Au and Ag on Si and Ge is of considerable interest for modern semi-conductor device applications. Several groups have investigated the room temperature growth of Au films on Ge (111) substrates using RHEED, LEED, UPS, as well as other techniques. It is clear from these investigations that the growth of Au on Ge (111) proceeds by a mechanism contrary to what might be expected by comparison to the growth of Au on Si (111). In general most of these studies have looked in two regimes, the first being simple room temperature growth over a wide range of Au coverages from a few tenths of a monolayer up to 100 Å in thickness. The second regime is the behavior of these Au films as a function of annealing temperature. Using RHEED and LEED to study a wide range of Au coverages, Le Lay and coworkers have found that the growth mechanism of Au films proceeds by the appearance of two dimensional close packed domains which do not completely cover the surface.

Mechanical Properties and Dislocation Structure of Single Crystal Cdte Deformed in Compression at 300°C

1976 ◽  
Vol 34 ◽  
pp. 592-593
Author(s):  
Ernest L. Hall ◽  
J. B. Vander Sande
Keyword(s):  
Mechanical Properties ◽  
Single Crystal ◽  
Dislocation Structure ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Strain Curve ◽  
Optical Devices ◽  
Semiconductor Compound ◽  
Wide Range ◽  
Sample Orientation

The present paper describes research on the mechanical properties and related dislocation structure of CdTe, a II-VI semiconductor compound with a wide range of uses in electrical and optical devices. At room temperature CdTe exhibits little plasticity and at the same time relatively low strength and hardness. The mechanical behavior of CdTe was examined at elevated temperatures with the goal of understanding plastic flow in this material and eventually improving the room temperature properties. Several samples of single crystal CdTe of identical size and crystallographic orientation were deformed in compression at 300°C to various levels of total strain. A resolved shear stress vs. compressive glide strain curve (Figure la) was derived from the results of the tests and the knowledge of the sample orientation.

Evaluation of 99mTc-Label led Vitamin K4 as an Agent for Testicular Imaging

1991 ◽  
Vol 30 (01) ◽  
pp. 35-39 ◽  
Author(s):  
H. S. Durak ◽  
M. Kitapgi ◽  
B. E. Caner ◽  
R. Senekowitsch ◽  
M. T. Ercan
Keyword(s):  
Soft Tissue ◽  
Room Temperature ◽  
Normal Subjects ◽  
Left Testis ◽  
Wide Range ◽  
Activity Ratios ◽  
The Right ◽  
Radioactivity Levels

Vitamin K4 was labelled with 99mTc with an efficiency higher than 97%. The compound was stable up to 24 h at room temperature, and its biodistribution in NMRI mice indicated its in vivo stability. Blood radioactivity levels were high over a wide range. 10% of the injected activity remained in blood after 24 h. Excretion was mostly via kidneys. Only the liver and kidneys concentrated appreciable amounts of radioactivity. Testis/soft tissue ratios were 1.4 and 1.57 at 6 and 24 h, respectively. Testis/blood ratios were lower than 1. In vitro studies with mouse blood indicated that 33.9 ±9.6% of the radioactivity was associated with RBCs; it was washed out almost completely with saline. Protein binding was 28.7 ±6.3% as determined by TCA precipitation. Blood clearance of 99mTc-l<4 in normal subjects showed a slow decrease of radioactivity, reaching a plateau after 16 h at 20% of the injected activity. In scintigraphic images in men the testes could be well visualized. The right/left testis ratio was 1.08 ±0.13. Testis/soft tissue and testis/blood activity ratios were highest at 3 h. These ratios were higher than those obtained with pertechnetate at 20 min post injection.99mTc-l<4 appears to be a promising radiopharmaceutical for the scintigraphic visualization of testes.

Porphyrin-Catalyzed Oxidation of N-Substituted Tetrahydroisoquinolines to Dihydroisoquinolones

Synlett ◽  
2021 ◽  
Author(s):  
Ao Li ◽  
Bin Pan ◽  
Mu Chao ◽  
Na Wang ◽  
Yu-Long Li ◽  
...  
Keyword(s):  
Visible Light ◽  
Room Temperature ◽  
Air Atmosphere ◽  
Wide Range ◽  
Convenient Route ◽  
Catalyzed Oxidation

A visible-light-induced direct α-oxygenation of N-substituted tetrahydroisoquinoline derivatives has been successfully developed. Metalloporphyrin (ZnTPP) has been identified as an effective and inexpensive photocatalyst for this transformation with a wide range of substrates. This protocol provides a convenient route to afford the desired products in moderate to good yields at room temperature under air atmosphere.

scholarly journals Plasmonic semiconductor nanogroove array enhanced broad spectral band millimetre and terahertz wave detection

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Jinchao Tong ◽  
Fei Suo ◽  
Tianning Zhang ◽  
Zhiming Huang ◽  
Junhao Chu ◽  
...  
Keyword(s):  
Surface Plasmon ◽  
High Performance ◽  
Room Temperature ◽  
Spectral Band ◽  
High Capacity ◽  
Terahertz Wave ◽  
Semiconductor Surface ◽  
Wide Range ◽  
Low Sensitivity ◽  
Air Interfaces

AbstractHigh-performance uncooled millimetre and terahertz wave detectors are required as a building block for a wide range of applications. The state-of-the-art technologies, however, are plagued by low sensitivity, narrow spectral bandwidth, and complicated architecture. Here, we report semiconductor surface plasmon enhanced high-performance broadband millimetre and terahertz wave detectors which are based on nanogroove InSb array epitaxially grown on GaAs substrate for room temperature operation. By making a nanogroove array in the grown InSb layer, strong millimetre and terahertz wave surface plasmon polaritons can be generated at the InSb–air interfaces, which results in significant improvement in detecting performance. A noise equivalent power (NEP) of 2.2 × 10−14 W Hz−1/2 or a detectivity (D*) of 2.7 × 1012 cm Hz1/2 W−1 at 1.75 mm (0.171 THz) is achieved at room temperature. By lowering the temperature to the thermoelectric cooling available 200 K, the corresponding NEP and D* of the nanogroove device can be improved to 3.8 × 10−15 W Hz−1/2 and 1.6 × 1013 cm Hz1/2 W−1, respectively. In addition, such a single device can perform broad spectral band detection from 0.9 mm (0.330 THz) to 9.4 mm (0.032 THz). Fast responses of 3.5 µs and 780 ns are achieved at room temperature and 200 K, respectively. Such high-performance millimetre and terahertz wave photodetectors are useful for wide applications such as high capacity communications, walk-through security, biological diagnosis, spectroscopy, and remote sensing. In addition, the integration of plasmonic semiconductor nanostructures paves a way for realizing high performance and multifunctional long-wavelength optoelectrical devices.

Sign in / Sign up

Export Citation Format

Share Document