Development of a method for fabricating metallic matrix composite shapes by a continuous mechanical process

Attempts made to develop processes capable of producing metal composites in structural shapes and sizes suitable for space applications are described. The processes must be continuous and promise to lower fabrication costs. Special attention was given to the aluminum boride (Al/b) composite system. Results show that despite adequate temperature control, the consolidation characteristics did not improve as expected. Inadequate binder removal was identified as the cause responsible. An Al/c (aluminum-graphite) composite was also examined

Dal and rice

I have always been a nostalgic person. I have boxes of old photographs, letters, birthday cards and objects from significant days in my life. I have confetti from different concerts, friendship bracelets and old diaries. While typically not represented by keepsakes, memories of food are some of my strongest. They encompass all five senses, which is perhaps why they are so powerful. Every time I smell a spice or taste something familiar, I am instantly transported to a certain place and time. As a textile artist, I use materials, textures, imagery, and senses to evoke place and time. This year in particular, I tried to bring a feeling of comfort back to the isolated existence I experienced in Providence in the midst of a global pandemic. Working with spices common in my family’s cooking and incorporating them into a textile allowed me to capture the comfort of scent; just the smell of a spice can trigger fond, powerful memories. Working with the concrete that is so prevalent in the marketplace and feeling its gritty texture at once took me back to the streets of Bangalore. Weaving with Sisal and Manila rope was reminiscent of the coconut trees I could see from my kitchen window. Through my current work, I want to not only comfort myself, but invite others to experience the warmth of my bustling kitchen and all the memories associated with it. These textiles are the materialization of nostalgia through food. In this thesis book, I write about four thesis works in a variety of styles— narrative, text, instructions and recipe—each exploring different facets of my studio practice, from personal history to process

Optional analyses of crossover trials having two treatments and a placebo

The assumption of carryover effects is unavoidable due to the very nature of crossover designs. Even in case of crossover design with washout period, the hypothesis of no carryover effect should be tested and established. On the other hand, this assumption makes the analysis difficult and potentially biased or inefficient in case of two treatment two period crossover design. For a reasonable estimation, experimenters are advocated to employ a two period three treatment crossover designs, or a three period two treatment crossover design. In this article, we present optional analyses of a uniform three period three treatment crossover design, consisting of a placebo and two active treatments. We develop a test for detecting presence of carryover effects which directs experimenter for a proper analysis of his crossover trial. We present ANOVA for each of the three possible carryover models, that both, single, or none of the active treatments has carryover effect, and illustrate through an example

Role of Surface Proteins in Magnetotaxis-based Applications

Magnetospirillum magneticum (AMB-1) are a species of magnetotactic bacteria that are capable of orienting along the earth’s magnetic field lines through their organelles called magnetosomes. Many studies have shown that certain engineered-bacteria can infect the tumor cells resulting in a controlled death of a tumor. This work deals with a technique utilizing AMB-1 along a predefined path through magnetotaxis, which can pave a way for selective doping as well as isolation of the tumor cells from a group of healthy cells through a magnetic invasive assay (MIA). For such a control, tiny mesh of vertical electrical coils each having a diameter of ~ 5 mm is fabricated, which establishes the path for the bacteria to move along the magnetic field lines. The molecular dynamics simulations at the interface of the bacterial cell surface proteins (MSP-1 & flagellin) and Chinese Hamster Ovary (CHO) cell surface containing cytoplasmic and extracellular proteins (BSG, B2M, SDC1, AIMP1, and FOS) will establish an association between the invading AMB-1 and the host CHO cells. The experimental demonstration will involve the CHO invasion by the AMB-1 and isolation of selected CHO cells. Statistical analysis along with the relevant electron and force microscopy data will confirm the number of AMB-1 and CHO cells involved before and after invasion and the role of directional control

Early Periprosthetic Metastasis Following Total Hip Replacement in a Patient With Breast Carcinoma: A Case Report and Review of Literature

Early periprosthetic osteolysis following total hip replacement (THR) as a result of septic etiology has been well understood. Periprosthetic bone loss as a result of metastatic infiltration is an uncommon and infrequent cause of early, progressive loosening of joint replacement prosthesis. Proximal femur has been the most common site of involvement compared to acetabular prosthesis. The rarity of this clinical entity can lead to delay in definitive diagnosis and management, thus affecting the final outcome. Breast is the commonest site of carcinoma in female patients despite which not many cases of periprosthetic metastasis have been reported in the literature. We present the first case of extensive, isolated periacetabular bone destruction following a THR in a 59 years old female patient with a history of breast carcinoma. Patients with known primary malignancy should be screened thoroughly before operation and should be followed regularly after joint replacement surgery to detect any metastatic foci around the prosthesis

Towards the Optimization of the Accelerated Crucible Rotation Technique Applied to the Gradient Freeze Growth of Cadmium Zinc Telluride via the Finite Element Method

University of Minnesota Ph.D. dissertation. 2017. Major: Chemical Engineering. Advisor: Jeffrey Derby. 1 computer file (PDF); 179 pages.Cadmium zinc telluride (CZT) is a semiconductor used for gamma ray detection in applications ranging from nuclear weapons monitoring to medical imaging. The production of CZT via the vertical gradient freeze (VGF) method is plagued by tellurium rich inclusions in the crystal that significantly decrease the detector performance. The accelerated crucible rotation technique (ACRT) is a promising approach for improving the production of detector-grade CZT crystals. ACRT, which repeatedly spins the crucible at varying rotation rates, was designed by Scheel and Schulz Du-Bois in the early 1970s as a means of controlling nucleation of new grains and reducing the size and density of inclusions. Despite the many improvements made in crystalline quality with the application of ACRT, little is understood with regard to how ACRT works to reduce inclusions, and few guidelines exist to help aid the selection of rotation schedules. Toward these ends, we have developed a realistic, comprehensive model based on the experimental set up at Washington State University (WSU). Finite-element methods are employed to solve the coupled phenomena of fluid mechanics, heat transfer, and solute transport in the VGF-ACRT system. We track the transport of tellurium and incorporate its thermodynamic effects on solidification phenomena. We show for the first time that the segregation of tellurium during growth drives constitutional supercooling. This supercooling is an indicator that a morphological instability has the potential to form and yield inclusions. Through a series of transient calculations, we aim to reduce the amount of supercooling via assessment of the transport phenomena and solidification dynamics. We present a thermodynamically based metric, which employs the classic instability criterion developed by Mullins and Sekerka, that represents the effect of ACRT on the stability along the solid-liquid interface. This metric is utilized for the comparison and optimization of rotation schedules. We find that, in contrast to conventional wisdom, slower rotation schedules that promote disruption of the solute field without disruption of the local interface velocities are found to be most favorable for the WSU system. Preliminary experimental evidence is presented that supports these findings

Using statistical metrology to understand pattern-dependent ILD thickness variation in oxide CMP processes

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (leaves 46-47).by Rajesh Ramji Divecha.M.Eng

Continuity in prestressed concrete beams

Call number: LD2668 .R4 1963 D61

Nuclei contain two differentially regulated pools of diacylglycerol

AbstractA number of recent studies have highlighted the presence of a nuclear pool of inositol lipids [1,2] that is regulated during progression through the cell cycle [1,3], differentiation [1,2] and after DNA damage [2], suggesting that a number of different regulatory pathways impinge upon this pool of lipids. It has been suggested that the downstream consequence of the activation of one of these nuclear phosphoinositide (PI) regulatory pathways is the generation of nuclear diacylglycerol (DAG) [1,3,4], which is important in the activation of nuclear protein kinase C (PKC) [5–7]. Activation of PKC in turn appears to regulate the progression of cells through G1 and into S phase [4] and through G2 to mitosis [3,8–11]. Although the evidence is enticing, there is as yet no direct demonstration that nuclear PIs can be hydrolysed to generate nuclear DAG. Previous data in murine erythroleukemia (MEL) cells have suggested that nuclear phosphoinositidase Cβ1 (PIC-β1) activity is important in the generation of nuclear DAG. Here, we demonstrate that the molecular species of nuclear DAG bears little resemblance to the PI pool and is unlikely to be generated directly by hydrolysis of these inositol lipids. Further, we show that there are in fact two distinct subnuclear pools of DAG; one that is highly disaturated and mono-unsaturated (representing more than 90% of the total nuclear DAG) and one that is highly polyunsaturated and is likely to be derived from the hydrolysis of PI. Analysis of these pools, either after differentiation or during cell-cycle progression, suggests that the pools are independently regulated, possibly by the regulation of two different nuclear phospholipase Cs (PLCs)