508 research outputs found
Interstitial Metal Impurities as a Possible Cause of Enhanced Reactivities / T. Behner, G. Elbers, S. Remme, F. Prissok, P. Stegger, and G. Lehmann
No full textElectrically conductive adhesive contacts characterised by the 1,f noise behaviour = Elektrisch leitende Klebkontakte charakterisiert durch das 1,f-Rauschverhalten
No full textBehner, Stella (Birth, 1898-12-16)
No full textAddress: 317 W. McMicken6045/Pg. 162/1898/F W/Germany/Germany/Mrs. WinterOriginal record filed in drawer labeled 'BECKMANN-BIERLE'
1/f Noise in conductive adhesive bonds under mechanical stress as a sensitive and fast diagnostic tool for reliability assessment
No full textClassical lifetime predictions of conductive adhesive bonds require time consuming thermal cycling measurements. Therefore, faster lifetime test are needed with more detailed information about degradation mechanisms. This paper reports on the low frequency noise of such contacts. Our results show that the evolution of l/f noise in contacts is a fast and non-destructive diagnostic tool for reliability testing. The l/f noise of the contact resistance can be interpreted within an existing contact noise model in terms of a multispot contact behaviour. In comparison to classical reliability tests, l/f noise measurements reveal more detailed information about reduction in the real electrical contact area and are much faster and are non-destructive
Influence of specific mutations on the biological activity of an African henipavirus surface glycoprotein
No full textHendra- und Nipahviren stellen die beiden hochpathogenen Vertreter des Genus
Henipavirus dar. Ihr natürlicher Wirt sind Flughunde der Gattung Pteropus. Während die
Infektion in Flughunden asymptomatisch verläuft, verursachen Henipaviren in Menschen
und anderen Säugetieren, wie Schweinen oder Pferden, schwerwiegende Infektionen
und gehören deshalb zu den sogenannten BSL-4 Erregern. Bis vor einigen Jahren ging
man davon aus, dass das Vorkommen der Henipaviren auf Südostasien und Australien
beschränkt ist. Inzwischen gibt es jedoch immer mehr Hinweise darauf, dass das
Verbreitungsgebiet der Henipaviren deutlich größer ist. So wurden beispielsweise in
Westafrika (Ghana) Henipavirus-ähnliche RNA-Sequenzen aus Flughunden der Spezies
Eidolon helvum isoliert. Eines dieser afrikanischen Henipaviren, Kumasivirus (KV),
konnte vollständig sequenziert werden. Da jedoch bis heute kein vermehrungsfähiges
Virus aus Flughunden isoliert werden konnte, kann das zoonotische Potential neuer
Henipaviren nur durch die funktionelle Charakterisierung einzelner viraler Proteine im
Vergleich zu den homologen Proteinen bekannter humanpathogener Henipaviren
abgeschätzt werden.
Die beiden viralen Oberflächenproteine G und F sind für den Eintritt von Henipaviren in
Wirtszellen und ihre Ausbreitung auf Nachbarzellen von zentraler Bedeutung. Nur wenn
das G-Protein erfolgreich an seinen zellulären Rezeptor gebunden hat und seine
sogenannte Fusionshelferfunktion ausübt, kann das F-Protein die Virus-Zell- oder die
Zell-Zell-Fusion einleiten. Es konnte bereits gezeigt werden, dass die
Oberflächenexpression und die Fusionshelferaktivität des KV-G Proteins im Vergleich
zu anderen Henipavirus Glykoproteinen deutlich reduziert ist. Um die Ursache hierfür
aufzuklären, wurde in dieser Arbeit das KV-G Protein im Vergleich zum G-Protein des
pathogenen Nipahvirus (NiV-G) auf molekularer Ebene charakterisiert. Dafür wurden
verschiedene Mutationen in das Protein eingefügt, die das N-Glykosylierungsmuster, die
Oligomerisierung oder die Endozytose des Proteins beeinflussten. Western Blot
Analysen, metabolische Markierungen sowie funktionelle Fusionsassays ergaben, dass
das KV-G Protein, wie auch das NiV-G, sechs N-Glykane besitzt, die alle für den
Oberflächentransport und die biologische Aktivität essentiell sind. Die Oligomerisierung
des KV-G Proteins scheint sich jedoch von der des NiV-G Proteins zu unterscheiden.
KV-G wird nicht in einem ausgewogenen Dimer-Tetramer-Verhältnis exprimiert, sondern
bildet hauptsächlich hocholigomere Formen aus. Cystein-Mutationen in der Stieldomäne
des KV-G Proteins führten zwar zu einer Veränderung des Oligomerisierungsmusters,
allerdings konnte weder die Oberflächenexpression noch die Fusionshelferfunktion
verbessert werden. Interessanterweise führte jedoch die Mutation eines nicht
konservierten Cysteins in der Kopfdomäne zu einer signifikant gesteigerten
Fusionshelferfunktion des KV-G Proteins. Die Aktivität konnte weiter gesteigert werden,
wenn zusätzlich das Endozytose-Motiv in der zytoplasmatischen Domäne zerstört
wurde.
In dieser Arbeit konnte zum ersten Mal eine signifikant gesteigerte Aktivität (gain of
function) eines Glykoproteins eines afrikanischen Henipavirus nachgewiesen werden.
Auch wenn die biologische Aktivität des KV-G Proteins im Vergleich zu Glykoproteinen
hochpathogener Henipaviren immer noch stark eingeschränkt ist, muss davon
ausgegangen werden, dass durch wenige adaptive Punktmutationen afrikanische
Henipaviren mit gesteigerter Funktion und damit eventuell höherem zoonotischen
Potential entstehen können.Hendra virus and Nipah virus are the two highly pathogenic representatives of the genus
henipavirus. Fruit bats of the genus Pteropus serve as their natural reservoir. While bats
do not show any clinical symptoms upon infection, henipaviruses can cause severe
illness after natural spillover to humans, pigs or horses. Due to their zoonotic potential
and high pathogenicity, henipaviruses are classified as BSL-4 pathogens. Initially,
henipaviruses were believed to be restricted to Southeast Asia and Australia. But in
recent years, there is increasing evidence of a much broaden geographic distribution
because henipaviral RNA has been identified also in Africa. One of these African bat
henipaviruses, Kumasi virus (KV), isolated from an Eidolon helvum fruit bat in Ghana,
could be fully sequenced. Since isolation of infectious viruses was not successful so far,
evaluation of the zoonotic potential of new viruses is based on functional analyses of
individual viral surface proteins in comparison to their pathogenic homologues from
Nipah or Hendra viruses.
The receptor-binding G protein and the fusion protein F are central determinants for virus
entry and cell-to-cell spread. Efficient binding to cellular receptors and fusion-helper
function of henipavirus G proteins are essentially required to support F-mediated viruscell and cell-cell-fusion processes. It has been shown earlier that surface expression and
fusion-helper activity of KV-G is clearly reduced compared to the G protein of pathogenic
NiV (NiV-G). To gain insight into the molecular determinants affecting protein transport
and function, several KV-G mutants resulting in changes in N glycosylation,
oligomerization and endocytosis pattern were generated. Western Blot analysis,
metabolic labeling and functional fusion assays revealed that, similar to NiV-G, KV-G
contains six N glycans which are all required for surface transport and functionality.
However, KV-G differs in its oligomerization by almost exclusively forming stable
tetramers, while NiV-G is expressed in a well-balanced dimer-tetramer ratio. Although
cysteine mutations in the stalk domain of KV-G altered the oligomerization pattern,
neither surface transport nor fusion-helper activity was improved. However, when
mutating a non-conserved cysteine in the globular head domain of KV-G some gain of
function was observed. This was further increased when we additionally disrupted an
endocytosis motive in the cytoplasmic domain. This work shows for the first time an
African henipavirus glycoprotein with enhanced functionality. Although the bioactivity is
still far below that of highly pathogenic henipavirus G proteins, this indicates that African
henipaviruses with improved fusion-helper function and perhaps an increased zoonotic
potential might evolve by just a few adaptive mutations
1/f Noise as a diagnostic tool to investigate the quality of isotropic conductive adhesive bonds
No full textReliability assessment of conductive adhesive bonds by thermo-cycling up to 830 cycles is time consuming, and does not give much information about the details of the onset of degradation. There is a need for faster tests giving more details about degradation. In this paper, low frequency noise of such contacts is investigated. 1/f Noise stems from conductance fluctuations. The observed voltage noise is enhanced due to current crowding in the electrical contacts on a microscopic scale. In this research contact bonds were made and compared of isotropic conductive adhesives from three suppliers. The 1/f noise of the contact resistance can be interpreted in terms of a multispot contact behavior. We investigated the relative noise C versus contact resistance R in two ways: (1) after an increasing number of thermo-cycles; (2) after increasing mechanical stress. The results often show an increase in relative noise of three orders of magnitude for poor quality polymer bonds. A maximum increase of one order of magnitude is observed for the best quality conductive adhesive. The contact resistance increases by a factor 1.7 and not more than 1.14 for the poor and best quality bonds, respectively. From the analysis based on a noise model for multispot contact, the onset of delamination can be characterized as a reduction in electrical contact area Ae. The relative noise is proportional to Ae-5/2. The surprising result is that samples submitted to a mechanical stress show pictures similar to thermocycled samples. Thermo-cycling with less than 200 cycles leads to less noise, an increase in electrical contact area, and hence a contact improvement. This behavior is understood. Noise analysis under mechanical stress on nondegraded or slightly cycled bonds is a fast diagnostic tool for reliability characterization. The degree of delamination is expressed quantitatively by the D-factor D=Aemax /Aemin¿(Cmax/Cmin)2/5
Letter from Mary to Father- January 18, circa 1925
No full textMary wrote this letter to her father in January of an unspecified year; she mentions her freshman class, which could place it in 1925. The letter is typewritten on two small cream sheets of paper. The backs of the letters contain short notes in pencil. Mary begins the letter by talking about two friends\u27 financial needs for college, mentions a revival service being held in Wooster, and talks about her dorm room. She and her roommate have a victrola and Mary requests that her parents send her some records to listen to.
Transcription:
1
Jan. 18
Dear dad
Started a letter to you yesterday but it was so interupted that I am beginning over again. We got a cut in Greek this first period so that I will be able to finish this and get it off on the same mail.
Your last letter sounded good… I do hope there can be something done for this Agnes Fayes. You are sure that the money is not borrowed but given??? There is also another girl in our fresh-man class who is all alone in the world. She has neither parents nor money. She doesn’t see how she can stay thru the ne next semester. She can borrow money f from the college but she hated to do t that. She has worked her way thru H.S. but of course college is different. To give you an idea of her keen wit and m mind, I think she would make a wonder-ful lawyer. Tell Esther to tell you about Jene Butterworth. She is not going to be a missionary tho so I suppose there is no way to help her. She is a tiny girl, loved by every one and not strong enough for the life of a miss.. Her friends at home are helping her. However Agnes Fayes is going to be a missionary andneeds [sic] it worse than Jene does now. Agnes belongs to a Pres. church in Blufton and Rev. King is the pastor. There would be no troub le [sic] to get recommendations because I know the circumstances. She is well acquanted [sic] with Prexie.
We are having revival services here in Wooster held by Bob Jones. The auditorium holds about 1500. I had a date coming home. Met Paul on the way home too, it was so funny.
2
Rev. Gaines 1450 - R”
Gay J E. Gaines
Smith
Geo. B. Jones. -831-
3
Sat. afternoon we cleaned our room thoroughly and it looks just swell now. It seems as if every one has been u p to see it since then. We arranged it differently too. Our new matron was here our nurse, some upper classmen and the DEAN and just loads of girls. They all just love this room but no more than we do. It is so homey and comforta ble.Our new victrola is just wonderful but there is ane [sic] more thing we desire. Boots got a special from home yesterday (She gets a special from her mother every Sunday) saying that they would send some go good records this week. We have our”vic.” now and we want to have good music in our room. We are tired of jaz.[sic] Could you send us some of the records you are not using. I wish you would do that real soon. It would help the atmosphere of our room much besides being nice for us
Must close this minuite [sic] an d rush to class
LOVE TO ALL Bean.
4
sar E.Wal. B. Potn. B. Teahttps://openworks.wooster.edu/marybehner_papers/1017/thumbnail.jp
Letter from Mary to Family- October 17, 1925
No full textMary wrote this letter to her family during the fall of her second year at college. The letter is written on four sheets of personalized Tea House stationery. Mary used blue ink, pencil, and black ink throughout the letter. In this letter, Mary begins by talking about needing her fur coat back from the tailor, then describes a trip to Cleveland, which included a football game, eating Chinese food, and visiting Keith\u27s Vaudeville Palace.
Transcription:
1
Sun Oct 17, 1925
Dear family.
Am at Boots this afternoon. It’s a lovely day. Sort of cold and snappy. Feel pretty good, even tho tired as might be expected after a day like yesterday.
Friday night Boots and I made some sandwiches for 11 girls - at the Tea House as we all wanted to eat breakfast in the car in the morning which left at 6:30 and we had to walk down town to get the car. It was cold and so (as it was looking a little rainy) I wore my atheletic [sic] sweater underneath my slicker. Would have worn my fur coat had it have been here. I think you are mistaken about
2/ the coat. The one you mention being cleaned was my [unclear] one - that was in the parcel past package. The coat (fur) you remember was at the Tailors being relined and wasn’t finished before I left and you said you would send it after it came back - when you got home after the trip. I imagine it is still at the Tailor on that one-way street. Wish you would get it & send it. Dad & I took it there. The sleeves were to be relined so I think you did not send it. However I went to the P.O. There was no record of it and they said to trace it from the other end.
We did not stay in Cleveland over night. We surely had one grand time
3. Sold some - lots of sandwiches on the car and made some “pin” money. Our bunch rode in the smoker. Of course it was a special college car & no one smoked. 11 of us. The trip cost me 6.00 & We went shopping in the morning and each bought a 10¢ c to wear to the game just an imitation one as the others cost 75¢ - It is our college flower and they looked so cute. Prexy & the coach always wear them on big game days. We had a grand cafeteria lunch.
And the game was wonderful. We made a touchdown in the first
4/
5 minutes and they made a touchdown in the last 2 min. Such excitement - But they missed the kickover so we won with a score 7-6. Boy some game as you can imagine. It was our immigration day so we had 3 or 400 rooters there. We with Wooster people all over the city shopping etc. We went to a marvelous oriental place! Boots & I had 1 chop suey 1 Yaiowen 1 egg F. together. Cost us 1.75 together. The kids danced between courses - Wonderful time. In the evening we went to Keith’s palace - Vaudavelle - It was cank & disgusting most of it - I guess most of the Wooster delegation were there
5 The Vic is now on - Just finished “Let me call you sweetheart and now playing “Let me call you sweet heart”
As I was saying - the Keiths Vaudavelle - Its appauling when one thinks of the thousands who are being entertained as such all over the country and how they really are being pleased.
We came home on the 11:30 car and ran all the way to get it - [unclear] was too peppy to sleep - but almost went to sleep in church_
We sang a beautiful anthem in church. Our new robes are so nice. Had a good dinner this noon. Have been teasing Boots - Shes trying to write a letter. The leaves are turning so quickly
6/ Glad I made “Doc” happy. He told me that he writes long letters I haven’t heard from him yet. I’m anxious to hear what he will say and how he will explain
Papa is home by now, I suppose
Will close now
Oh no - will answer your questions in the last letter. When I go to see Boots I sleep with her. Sometimes her roommate is there & sometimes she goes up stairs with her gang.
My sneezing has subsided but not stopped altogether
7/
You never saw College Hall. It’s a missionary project in the Italian district - sort of a community house which the college supports.
Our car arrived home at 2:00 Clock Sun. morning
Did Dad see any of our people in St. Louis How about Evelyn Miller. Tell me all about it.
My dress & shirts all came thru beautifully My rain coat is trimmed.
C.E. topic tonight. “Is Campus life real life?” My love to all
Your Mary Elizabeth.
Boots heard from Esther.
Did you send E. Joanne\u27s package to 94 5 1/2 17th St. ?
Please
missed Dad’s S.S. lesson last week from paperhttps://openworks.wooster.edu/marybehner_papers/1043/thumbnail.jp
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