Transport properties of layered fabric systems based on electrospun nanofibers     

Seungsin Lee  S. Kay Obendorf 《Fibers and Polymers》2007,8(5):501-506

Layered fabric systems with electrospun polyurethane fiber web layered on spunbonded nonwoven were developed to examine the feasibility of developing protective textile materials as barriers to liquid penetration using electrospinning. Barrier performance was evaluated for layered fabric systems, using pesticide mixtures that represent a range of surface tension and viscosity. Air permeability and water vapor transmission were assessed as indications of thermal comfort performance. Protection performance and air/moisture vapor transport properties were compared for layered fabric systems and existing materials for personal protective equipment (PPE). Layered fabric systems with electrospun nanofiber web showed barrier performance in the range between microporous materials and nonwovens used for protective clothing. Layered fabric structures with the web area density of 1.0 and 2.0 g/m² exhibited air permeability higher than most PPE materials currently in use; moisture vapor transport was in a range comparable to nonwovens and typical woven work clothing fabrics. Comparisons of layered fabric systems and currently available PPE materials indicate that barrier/transport properties that may not be attainable with existing PPE materials could be achieved from layered fabric systems with electrospun nanofibrous web.  相似文献   

Physical Characteristics of Genetically Altered Wheat Related to Technological Protein Separation     

George H. Robertson  Ann E. Blechl  William J. Hurkman  Olin D. Anderson  Trung K. Cao  Charlene K. Tanaka  Kay S. Gregorski  William J. Orts 《Cereal Chemistry》2013,90(1):1-12

Wheat protein is a technologically challenging substrate for food and nonfood applications because of its compositional diversity and susceptibility to denaturation. Genetic modification could be used to create cultivars capable of producing more uniform or focused and novel protein compositions targeted to nonfood uses. These lines could serve as expression systems for specific high‐molecular‐weight (HMW) protein polymers and would be new crops leading to more diverse agricultural opportunities. However, fundamental changes to the molecular architecture in such wheat seeds could also result in separation and processing issues, such that conventional methods of protein enrichment may need modification or even reinvention. Enriched gluten protein fractions were prepared from Bobwhite lines modified to overproduce HMW glutenin subunits Dx5 and/or Dy10. These lines serve as experimental models to test various approaches that may be taken for protein polymer enrichment. However, conventional wheat gluten enrichment based on the glutomatic as a small model of industrial methods was incapable of producing enrichment for any of the tested meal or flour, including that from the non‐transformed parent Bobwhite. Mixing in the mixograph or farinograph failed to produce standard patterns for whole kernel meal and straight‐run flour, and the normal cohesiveness of dough expected from these devices was not observed. Microscopy of stained dough samples revealed severely limited formation of normal protein networks, a capability crucial to conventional separation technology. Particle size analysis of whole kernel meal revealed a higher resistance to milling for the altered lines. Higher drying rates, lower farinograph moisture absorption, and increased thermal transition temperatures were observed. These data suggested that the native architecture of these new forms was more tightly constructed with reduced capacity for alteration by hydration and input of mechanical energy. An alternative enrichment method featuring solvation in SDS and precipitation in acetone produced coagulated (Bobwhite) or partially coagulated protein (transgenic lines producing Dx5 or Dy10) enriched to 78–85% protein with high yield.  相似文献   

A needs-assessment and demographic survey of infection-control and disease awareness in western US animal shelters     

Steneroden KK  Hill AE  Salman MD 《Preventive veterinary medicine》2011,98(1):52-57

A cross-sectional needs-assessment survey was used to characterize animal shelters in a 6-state region in the western US and describe infection-control practices and disease awareness. Survey questions focused on shelter demographics, infection-control practices and policies, awareness and concern over infectious and zoonotic diseases, staff and volunteer training relating to infection-control and disease awareness, use of diagnostic tools, and isolation procedures and protocols. Fifty percent of shelters responded to the survey and represented a wide variety of shelter types, sizes and locations. The top-three diseases of concern to shelters were feline upper respiratory disease (FURD), canine parvovirus and ringworm. Concern over these diseases was greater in open-admission shelters (compared to limited admission or no-kill/sanctuary) (OR 3.7, 95% CI 1.1-12.5) and in shelters with a desire for more zoonotic-disease training (OR=6.1, 95% CI 1.5-24.8) (compared to shelters desiring infectious-disease training, training on cleaning and disinfection or those who have no need for further training). In 45% of responding shelters many to most animals arrive with infectious diseases. Written protocols for preventive medicine exist in 88% of shelters, cleaning and disinfection protocols in 75%, specific disease protocols for outbreak situations in 36% and infection-control manuals in 15%. Veterinarians are in charge of infection-control in 6% of shelters. Approximately 45% of shelters vaccinate dogs and cats for rabies. Infectious-disease training is provided to 30% of staff and 35% of volunteers upon hire. Overall, volunteers received less training in infectious- and zoonotic-disease identification, prevention and control than staff members. Ninety percent of shelters said they would benefit from training in infectious and zoonotic disease. Results from this study can be used to assess and address needs in animal shelters relating to infection-control, infectious and zoonotic-disease awareness and can help guide development of shelter staff and volunteer training.  相似文献   

Clonal complex Pseudomonas aeruginosa in horses     

Kidd TJ  Gibson JS  Moss S  Greer RM  Cobbold RN  Wright JD  Ramsay KA  Grimwood K  Bell SC 《Veterinary microbiology》2011,149(3-4):508-512

Pseudomonas aeruginosa is associated with infectious endometritis in horses. Although infectious endometritis is often considered a venereal infection, there is relatively limited genotypic-based evidence to support this mode of transmission. The study sought to determine the relatedness between genital P. aeruginosa isolates collected from a limited geographical region using molecular strain typing. Enterobacterial repetitive intergenic consensus PCR typing was performed on 93 isolates collected between 2005 and 2009 from 2058 thoroughbred horses (including 18 stallions) at 66 studs. While P. aeruginosa was not detected in the stallions, 53/93 (57%) mares harbouring P. aeruginosa had clonally related strains, which included a single dominant genotype detected in 42 (45%) mares from 13 different studs. These novel findings suggest that most equine genital P. aeruginosa infections in this region may have been acquired from mechanisms other than direct horse to horse transmission. Instead, other potential acquisition pathways, as well as strain specific adaptation to the equine genital tract, should be investigated.  相似文献   

Suspected seminal vesiculitis in an Asian elephant (Elephas maximus)     

Kilburn JJ  Velguth KE  Backues KA 《Journal of zoo and wildlife medicine》2011,42(3):485-489

A 32-year-old male Asian elephant (Elephas maximus) underwent routine transrectal stimulation for semen collection as part of an artificial insemination program. The procedure consisted of a preinsemination semen collection followed by two consecutive days of semen collections for artificial insemination. The second day's sample contained large numbers of inflammatory cells, intracellular bacteria, and phagocytized sperm. Semen was submitted for culture and sensitivity. Culture revealed Acinetobacter lwoffii, Staphylococcus intermedius, Kocuria roseus, and an unidentified gram-positive organism. Empirical antibiotic therapy with trimethoprim sulfa was initiated and then changed to enrofloxacin based on sensitivity panel results for a total of 28 days of treatment. Diagnostic semen collections were performed during treatment and 2 wk posttreatment to determine the success of therapy. Posttreatment collections revealed resolution of the inflammation. The origin of the infection was suspected to be the seminal vesicles.  相似文献   

Orchestrated transcription of key pathways in Arabidopsis by the circadian clock   总被引：3，自引：0，他引：3  

Harmer SL  Hogenesch JB  Straume M  Chang HS  Han B  Zhu T  Wang X  Kreps JA  Kay SA 《Science (New York, N.Y.)》2000,290(5499):2110-2113

Like most organisms, plants have endogenous biological clocks that coordinate internal events with the external environment. We used high-density oligonucleotide microarrays to examine gene expression in Arabidopsis and found that 6% of the more than 8000 genes on the array exhibited circadian changes in steady-state messenger RNA levels. Clusters of circadian-regulated genes were found in pathways involved in plant responses to light and other key metabolic pathways. Computational analysis of cycling genes allowed the identification of a highly conserved promoter motif that we found to be required for circadian control of gene expression. Our study presents a comprehensive view of the temporal compartmentalization of physiological pathways by the circadian clock in a eukaryote.  相似文献   

Electricity in Agriculture     

Dimmock G 《Science (New York, N.Y.)》1892,19(472):109

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Three-dimensional structure of herpes simplex virus from cryo-electron tomography     

Grünewald K  Desai P  Winkler DC  Heymann JB  Belnap DM  Baumeister W  Steven AC 《Science (New York, N.Y.)》2003,302(5649):1396-1398

Herpes simplex virus, a DNA virus of high complexity, consists of a nucleocapsid surrounded by the tegument-a protein compartment-and the envelope. The latter components, essential for infectivity, are pleiomorphic. Visualized in cryo-electron tomograms of isolated virions, the tegument was seen to form an asymmetric cap: On one side, the capsid closely approached the envelope; on the other side, they were separated by approximately 35 nanometers of tegument. The tegument substructure was particulate, with some short actin-like filaments. The envelope contained 600 to 750 glycoprotein spikes that varied in length, spacing, and in the angles at which they emerge from the membrane. Their distribution was nonrandom, suggesting functional clustering.  相似文献   

Circadian clocks in daily and seasonal control of development     

Schultz TF  Kay SA 《Science (New York, N.Y.)》2003,301(5631):326-328

The rotation of the earth results in regular changes in the light environment, and organisms have evolved a molecular oscillator that allows them to anticipate these changes. This daily molecular oscillator, known as the circadian clock, regulates a diverse array of physiologies across a wide variety of organisms. This review highlights a few of the insights we have into circadian clock regulation of development, in both plants and animals. A common thread linking plants and animals is the use of the circadian clock to sense changes in day length and to mediate a diverse number of photoperiodic responses.  相似文献   

Comment on "Grasping primate origins"     

Kirk EC  Cartmill M  Kay RF  Lemelin P 《Science (New York, N.Y.)》2003,300(5620):741; author reply 741

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