7,665 research outputs found
TACC3-ch-TOG track the growing tips of microtubules independently of clathrin and Aurora-A phosphorylation
No full textThe interaction between TACC3 (transforming acidic coiled coil protein 3) and the microtubule polymerase ch-TOG (colonic, hepatic tumor overexpressed gene) is evolutionarily conserved. Loading of TACC3–ch-TOG onto spindle microtubules requires the phosphorylation of TACC3 by Aurora-A kinase and the subsequent interaction of TACC3 with clathrin to form a microtubule binding surface. Whether there is a pool of TACC3–ch-TOG that is independent of clathrin in human cells, and what is the function of this pool, are open questions. Here, we report that TACC3 is recruited to the plus-ends of microtubules by its association with ch-TOG and that this pool is independent of phosphorylation and binding to clathrin. The plus-end binding of TACC3–ch-TOG persists in interphase and we propose that one cellular function of TACC3–ch-TOG is to modulate cell migration. We also describe the distinct subcellular pools of TACC3, ch-TOG and clathrin. TACC3 is often described as a centrosomal protein, but we show that there is no significant population of TACC3 at centrosomes. The delineation of distinct protein pools reveals a simplified view of how these proteins are organized and controlled by post-translational modification
A One Transistor RAM for MPC Projects
No full textMany MPC projects, such as video frame buffers, need a large memory subsystem. A one transistor per bit dynamic memory using Mead-Conway design rules is being designed with this purpose in mind. The memory cell size is 16.5 λ by 8λ (about the same size as a 1975 4K RAM cell with λ = 2.5 microns).
While a complete high density memory subsystem has not been designed, two chips have been designed to test its major components. One chip is a 1K memory array that tests the sense amplifier, column decoder/driver, and read/write logic. This chip lacks a timing generator and clock drivers. The second chip tests some low power bootstrapped clock drivers. These test chips are currently being fabricated
COUPLING OF THE C-H STRETCH TO LARGE-AMPLITUDE TORSION AND INVERSION MOTIONS: COMPARISON OF CHCH, CHOH AND CHNH
No full textAuthor Institution: Department of Polymer Science and Department of Chemistry, The University of Akron; Department of Chemistry, The University of Akron, OH 44325In each of the title molecules, torsional and inversion tunneling occurs between six equivalent minima. Coupling of these degrees of freedom to the CH stretch occurs via variation of the C-H stretching force constants as a function of the torsional () and inversion () angles. Maps of the couplings have been computed at the MP2/6-311++G(3df,2p) level. Both the single bond CH stretch force constants and the bilinear couplings between CH bonds are presented as a function of and . Although the torsional barriers differ by more than a factor of 20, the torsion-inversion-vibration coupling patterns are very similar for CHNH and CHCH. On the other hand, the torsion-inversion-vibration coupling in the charged species CHOH is much weaker
Achieving large acoustic and phonon band gaps in multilayered structures
No full textBand gaps in the vibrational spectrum of periodic multi layer structures offer excellent opportunities to control acoustic waves and phonons. Engineering the characteristics of the band gaps requires a careful selection of layer materials and thicknesses. This paper aims to develop general guidelines for material and geometry selection to maximize band gaps in the elastic wave spectrum of binary multilayer structures. We calculate band gaps for a wide range of layer thickness fractions and material properties using an analytical solution for plane wave propagation normal to the layers. The behavior of the maximum band gap and the midgap frequency is captured into empirical relations which allow optimal layer materials and thicknesses to be selected. Their use is demonstrated with specific promising material systems for oxide-based thermoelectric applications, which show the possibility of band gaps on the order of the midgap frequency. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimDFG [SPP-1386, SFB 1073
NATURE OF TORSION-INVERSION COUPLING IN CHNH, CHOH AND CHCH
No full textAuthor Institution: Department of Chemistry, The University of Akron, OH; 44325-3601Two-dimensional torsion-inversion surfaces for methylamine, protonated methanol and ethyl radical were calculated and fit to a function containing a polynomial in the inversion angle() and trigonometric functions of the torsional angle(). Calculations were done at the B3LYP, MP2, and CCSD(T) levels with the 6-311++G(d,p) and 6-311++G(3df, 2p) basis sets and partial optimization. CHNH, CHOH and CHCH have G symmetry with 6-equivalent minima which are located by the various calculations at inversion angles 6.5 to 11; 42 to 45.5 and 52.5 to 55 degrees respectively on either side of planar. The three molecules have very different barriers to inversion ranging from no barrier for CHCH to 838 cm for CHOH to 1837 cm for CHNH. The dominant torsion-inversion coupling term in all cases has the form
The development, optimisation and testing of an unmanned parafoil launch system
No full textIncludes summary.Includes bibliographical references (leaves 70-73).Parafoils have been used in various aerospace, military and sport applications to return both personnel and payloads safely to the ground. Deflection of the trailing edge flaps by means of control lines allows for turn rates of up to 60° per second, which provides superior controllability when compared to conventional round parachutes. This steering ability has led to the development of autonomous control systems that are able to navigate a payload to land in close proximity to a designated landing site. In order to develop an autonomous navigation system a suitable dynamic model of the parafoil with suspended payload is required to determine the parameters and characteristics of the system in free flight. Flexible ram-air inflated parafoils display high sensitivity to atmospheric disturbances which complicates the comparison of measured flight-dynamic data to theoretical models in an open air free flight test. In order to improve the quality of results in studying the flight dynamics of an unmanned parafoil system in free flight, controlled conditions and a repeatable flight path are required to perform data analysis for various trim configurations. This leads to the requirement of a launching system that ensures consistent inflation of the canopy and repeatable launch velocities for various canopy and payload configurations
The Aurora RAM Compiler
No full textAbstract- This paper describes a RAM compiler for generating and characterizing highly manufacturable optimized SRAMs using GaAs E/D MESFET technology. The compiler uses a constraint-driven design flow to achieve process tolerant RAMs. This compiler was built using a flexible design framework that can be easily adapted to optimize and characterize memories in different MESFET processes. I
Negotiating work: Indigenous labour market report and development plan
No full textVeronic Arbon, Allan Arnott, Margaret Ayre, Ray Blohm, Mike Grenfell, Ailsa Purdon, Ram Vemuri and Greg WearneCh. 1. Introduction to the research -- Ch. 2. The economic context of the ILM -- Ch. 3. The social and cultural context of the ILM -- Ch. 4. The institutional context of the ILM -- Ch. 5. Labour market interventions -- Ch. 6. Education and training -- Ch. 7. The way ahead
Les diminutifs basques avec ch
No full textSe presentan formaciones similares a los diminutivos vascos con "ch" en España y América latina. Se dan ejemplosThe author introduces similar formations to the Basque diminutive "ch" in Spain and Latin America. Examples are provide
Cryopreservation and evalution akkaraman ram semen with cholesterol and 7-dehydrocholesterol
No full textBu araştırmada, ülkemize özgü bir ırk olan Akkaraman koç spermasının dondurulması ve çözdürülmesinde, kolesterol (ch) ve kolesterolün oluşumunda ara ürün olan 7- dehidrokolesterolün (7-dhc) tris sulandırıcısına eklenerek hazırlanmış solüsyonlarla elde edilecek in vitro sonuçların değerlendirilmesi amaçlandı. Araştırmada üç baş koç kullanıldı. Koçlardan haftada iki defa suni vajen yardımıyla sezon içinde sperma alındı. Her bir koçtan alınan nativ ejakülatlar birleştirildi. Birleştirilen ejekülatlar 7 eşit gruba bölündü (split ejekulat); biri kontrol grubu olarak ayrıldı; üçü ch'nin; diğer üçü de 7-dhc'nin farklı konsantrasyonları (1,5, 2,5, 3,5 mg/120x106) ile hazırlanarak tris sulandırıcısı oluşturuldu. Deneydeki sulandırıcı grupları ile dozlanan spermalar + 4 derecede 2 saat alışıma bırakıldı. Alışım süresi sonunda payetler sıvı azot buharında – 120oC 'de 15 dakikada dondurulduktan sonra sıvı azot içinde saklandı. Dondurulduktan 2 ay sonra her deneydeki gruplar için payetler 37oC'deki su banyosunda 35 saniyede çözdürüldü. Çözdürme sonrası spermatozoa motilitesi, anormal spermatazoa oranı sperma analiz cihazında (CASA) değerlendirildi. Plazma membran bütünlüğünün değerlendirilmesi için HOS test, DNA fragmentasyonu için COMET, spermatazoa canlılığı SYBR-14/PI, akrozom bütünlüğü FITC-PNA/PI, mitokondriyel aktivitasyon JC-1/PI; apoptozisin tespiti için Annexin V/PI yöntemi uygulandı. Ayrıca, antioksidan etkisinin değerlendirilmesi için lipit peroksidasyona (LPO) bakıldı.Çözüm sonrası motilite, ölü/canlı, akrozom hasarı, ve HOS test yönünden 7dhc grupları ile ch grupları arasında istatistiksel olarak aralarında bir fark bulunmazken; kontrol gruplarına göre istatistiksel olarak fark bulunmuştur (p0,05). Ayrıca, apoptosis yönünden veriler incelendiğinde canlı ve erken apoptosis hücrelerinde istatistiksel farklılıklar görülürken (p0,05). Sonuç olarak; Ch ve 7-dhc'nin koç spermasını dondurma (soğuk şoku) ve çözdürme prosedürlerine karşı koruduğu, 7-dhc'nin ch yerine koç spermasının sulandırılması ve dondurulmasında kullanılabileceği; ayrıca, ch ve 7-dhc ile elde edilen in vitro sonuçların dölverimlerinin de alınarak sağlamasının yapılması gerektiği sonucuna varıldı.In this research the evaluation of in vitro results of cholesterol (ch) and 7-dehydrocholesterol (7-dhc) which intermediates formation of cholesterol added to tris extenders in freezing-thawing of Akkaraman ram semen, a particular breed in our country, was aimed. In this reseasrch 3 rams were used. Semen was collected from the bucks by artificial vagina, twice a week, during the breeding season. The native ejaculates from each ram were mixed. The mixed ejaculates were divided into seven groups (split ejaculates). One of these was seperated as control, three were diluted with tris which have different concentrations of ch,and the other three were diluted with tris which have different 7-dhc concentrations (1,5, 2,5, 3,5). Extender groups in the experiment were equilibrated in +4°C Straws were frozen in liquid nitrogen vapour (-120 °C) and kept in liquid nitrogen at the end of equilibration period. 2 months after the straws were frozen, they were thawed in 37°C water bath for 35 seconds. Post-thaw spermatological parameters (motility, abnormal spermatozoa) were evaluated with the sperm analyser (CASA). HOS test for evaluating plasma membrane integrity, COMET for detecting DNA fragmentation, SYBR-14PI for detecting live/dead spermatozoa ratio, FITC-PNA/PI for evaluating acrosomal integrity, JC-1 with fluorescent stains for determining mitochondrial activity and Annexin V/PI method with flow cytometry for detecting apoptosis were performed. Besides, antioxidant effect was examined by lipid peroxidation. After thawing, there was no significant difference between 7-dhc and ch groups in terms of motility, live/dead spermatozoa ratio, acrosome defect, mitochondrial activation, and HOS tests; however statistically significant difference was detected when these were compared with control groups (p0,05). As a result, it was concluded that ch and 7-dhc protect ram semen from freezing (cold shock) and thawing procedures; 7-dhc can be used instead of ch for extending and freezing ram semen. In vitro results obtained with ch and 7-dhc should be double-checked with fertility results
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