Hydrostatic Pressure Testing of a Square-Cross Section Stainless Steel Propellant Tank Manufactured Using Selective Laser Sintering

The purpose of this study was to determine if parts manufactured using metal selective laser sintering (SLS) exhibit the same isotropic material properties as conventionally made metal parts. This was accomplished by performing a hydrostatic pressure test (HPT) of a metal SLS manufactured propellant tank, constructed for a nano-satellite of the cubesat class. Strain measurements from twelve strain gage locations on the propellant tank were recorded. A finite element analysis (FEA) model, which assumes isotropic material properties, was generated and a FEA analysis was ran at several pressure loads. The tanks strain data at the corresponding pressure loads from the HPT was then compared to the FEA data at the same pressure loads ranging from 500 to 3000psi. The two data sets were used for comparing material properties of the metal SLS and of theisotropic FEA model of the tank

Automating and Calibrating a Scanning Tunneling Microscope for Use in an Advanced Laboratory Course

University of Redlands student Jonathan Paez and I worked on automating and calibrating a student constructed scanning tunneling microscope (STM) with the intention of using it for pedagogical purposes in an advanced laboratory course. We automated the STM by incorporating a linear actuator and LabVIEW. We were successful in creating three dimensional plots of graphite and gold surfaces and deriving calibrations to convert our data from voltages to distances. We discovered that our STM has nanometer-scale resolution

Trophoblast biology: Forum introduction

In mammals, a carefully orchestrated dialogue between the mother and conceptus (embryo/fetus and associate extraembryonic membranes) is initiated during the peri-implantation period of pregnancy as the trophoblast develops, functions to signal pregnancy recognition, and initiates implantation. The purpose of this Forum is to highlight comparative aspects of trophoblast morphogenesis and function in mammals

Conceptus signals for establishment and maintenance of pregnancy

Establishment and maintenance of pregnancy results from signaling by the conceptus (embryo/fetus and associated extraembryonic membranes) and requires progesterone produced by the corpus luteum (CL). In most mammals, hormones produced by the trophoblast maintain progesterone production by acting directly or indirectly to maintain the CL. In domestic animals (ruminants and pigs), hormones from the trophoblast are antiluteolytic in that they act on the endometrium to prevent uterine release of luteolytic prostaglandin F2 alpha (PGF). In cyclic and pregnant sheep, progesterone negatively autoregulates expression of the progesterone receptor (PR) gene in the endometrial luminal (LE) and superficial glandular epithelium (GE). Available evidence in cyclic sheep indicates that loss of the PR is closely followed by increases in epithelial estrogen receptors (ER) and then oxytocin receptors (OTR), allowing oxytocin to induce uterine release of luteolytic PGF pulses. In pregnant sheep, the conceptus trophoblast produces interferon tau (IFN tau) that acts on the endometrium to inhibit transcription of the ER alpha gene directly and the OTR gene indirectly to abrogate development of the endometrial luteolytic mechanism. Subsequently, sequential, overlapping actions of progesterone, IFN tau, placental lactogen (PL) and growth hormone (GH) comprise a hormonal servomechanism that regulates endometrial gland morphogenesis and terminal differentiated function to maintain pregnancy in sheep. In pigs, the conceptus trophoblast produces estrogen that alters the direction of PGF secretion from an endocrine to exocrine direction, thereby sequestering luteolytic PGF within the uterine lumen. Conceptus estrogen also increases expression of fibroblast growth factor 7 (FGF-7) in the endometrial LE that, in turn, stimulates proliferation and differentiated functions of the trophectoderm, which expresses the FGF-7 receptor. Strategic manipulation of these physiological mechanisms can offer therapeutic schemes to improve uterine capacity, conceptus survival and reproductive health

Refuge or Reservoir? The Potential Impacts of the Biofuel Crop Miscanthus x giganteus on a Major Pest of Maize

BACKGROUND: Interest in the cultivation of biomass crops like the C4 grass Miscanthus x giganteus (Miscanthus) is increasing as global demand for biofuel grows. In the US, Miscanthus is promoted as a crop well-suited to the Corn Belt where it could be cultivated on marginal land interposed with maize and soybean. Interactions (direct and indirect) of Miscanthus, maize, and the major Corn Belt pest of maize, the western corn rootworm, (Diabrotica virgifera virgifera LeConte, WCR) are unknown. Adding a perennial grass/biomass crop to this system is concerning since WCR is adapted to the continuous availability of its grass host, maize (Zea mays). METHODOLOGY/PRINCIPAL FINDINGS: In a greenhouse and field study, we investigated WCR development and oviposition on Miscanthus. The suitability of Miscanthus for WCR development varied across different WCR populations. Data trends indicate that WCR populations that express behavioural resistance to crop rotation performed as well on Miscanthus as on maize. Over the entire study, total adult WCR emergence from Miscanthus (212 WCR) was 29.6% of that from maize (717 WCR). Adult dry weight was 75-80% that of WCR from maize; female emergence patterns on Miscanthus were similar to females developing on maize. There was no difference in the mean no. of WCR eggs laid at the base of Miscanthus and maize in the field. CONCLUSIONS/SIGNIFICANCE: Field oviposition and significant WCR emergence from Miscanthus raises many questions about the nature of likely interactions between Miscanthus, maize and WCR and the potential for Miscanthus to act as a refuge or reservoir for Corn Belt WCR. Responsible consideration of the benefits and risks associated with Corn Belt Miscanthus are critical to protecting an agroecosystem that we depend on for food, feed, and increasingly, fuel. Implications for European agroecosystems in which Miscanthus is being proposed are also discussed in light of the WCR's recent invasion into Europe

Amino acids in the uterine luminal fluid reflects the temporal changes in transporter expression in the endometrium and conceptus during early pregnancy in cattle

In cattle, conceptus-maternal interactions are critical for the establishment and maintenance of pregnancy. A major component of this early interaction involves the transport of nutrients and secretion of key molecules by uterine epithelial cells to help support conceptus development during the peri-implantation period of pregnancy. Objectives were to: 1) analyze temporal changes in the amino acid (AA) content of uterine luminal fluid (ULF) during the bovine estrous cycle; 2) understand conceptus-induced alterations in AA content; 3) determine expression of AA transporters in the endometrium and conceptus; and 4) determine how these transporters are modulated by (Progesterone) P4. Concentrations of aspartic acid, arginine, glutamine, histidine, lysine, isoleucine, leucine, phenylalanine and tyrosine decreased on Day 16 of the estrous cycle but increased on Day 19 in pregnant heifers (P < 0.05). Glutamic acid only increased in pregnant heifers on Day 19 (P,0.001). Asparagine concentrations were greater in ULF of cyclic compared to pregnant heifers on Day 7 (P < 0.05) while valine concentrations were higher in pregnant heifers on Day 16 (P < 0.05). Temporal changes in expression of the cationic AA transporters SLC7A1 SLC7A4 and SLC7A6 occurred in the endometrium during the estrous cycle/early pregnancy coordinate with changes in conceptus expression of SLC7A4, SLC7A2 and SLC7A1 (P < 0.05). Only one acidic AA transporter (SLC1A5) increased in the endometrium while conceptus expression of SLC1A4 increased (P < 0.05). The neutral AA transporters SLC38A2 and SLC7A5 increased in the endometrium in a temporal manner while conceptus expression of SLC38A7, SLC43A2, SLC38A11 and SLC7A8 also increased (P < 0.05). P4 modified the expression of SLC1A1, -1A4, -1A5, -38A2 , -38A4, -38A7, -43A2, -6A14, -7A1, -7A5 and -7A7 in the endometrium. Results demonstrate that temporal changes in AA in the ULF reflect changes in transporter expression in the endometrium and conceptus during early pregnancy in cattle, some of which are modified by P4. © 2014 Forde et al

Effects of the estrous cycle, pregnancy and interferon tau on expression of cyclooxygenase two (COX-2) in ovine endometrium

In sheep, the uterus produces luteolytic pulses of prostaglandin F(2α )(PGF) on Days 15 to 16 of estrous cycle to regress the corpus luteum (CL). These PGF pulses are produced by the endometrial lumenal epithelium (LE) and superficial ductal glandular epithelium (sGE) in response to binding of pituitary and/or luteal oxytocin to oxytocin receptors (OTR) and liberation of arachidonic acid, the precursor of PGF. Cyclooxygenase-one (COX-1) and COX-2 are rate-limiting enzymes in PGF synthesis, and COX-2 is the major form expressed in ovine endometrium. During pregnancy recognition, interferon tau (IFNτ), produced by the conceptus trophectoderm, acts in a paracrine manner to suppress development of the endometrial epithelial luteolytic mechanism by inhibiting transcription of estrogen receptor α (ERα) (directly) and OTR (indirectly) genes. Conflicting studies indicate that IFNτ increases, decreases or has no effect on COX-2 expression in bovine and ovine endometrial cells. In Study One, COX-2 mRNA and protein were detected solely in endometrial LE and sGE of both cyclic and pregnant ewes. During the estrous cycle, COX-2 expression increased from Days 10 to 12 and then decreased to Day 16. During early pregnancy, COX-2 expression increased from Days 10 to 12 and remained higher than in cyclic ewes. In Study Two, intrauterine infusion of recombinant ovine IFNτ in cyclic ewes from Days 11 to 16 post-estrus did not affect COX-2 expression in the endometrial epithelium. These results clearly indicate that IFNτ has no effect on expression of the COX-2 gene in the ovine endometrium. Therefore, antiluteolytic effects of IFNτ are to inhibit ERα and OTR gene transcription, thereby preventing endometrial production of luteolytic pulses of PGF. Indeed, expression of COX-2 in the endometrial epithelia as well as conceptus is likely to have a beneficial regulatory role in implantation and development of the conceptus

The influence of the Boer War (1899-1902) on the tactical development of the regular British Army 1902-1914

This thesis examines the influence of the Boer War 1899 – 1902 upon tactics and training in the regular British Army 1902 – 1914. The work argues that several key lessons drawn from South Africa became the tactical cornerstones for infantry, artillery and cavalry throughout the pre-First World War period and shaped the performance of the B.E.F. during the early battles of 1914. The experience of combat against well armed opposition in the Boer War prompted the British Army to develop improved tactics in each of the three major service arms. For example, infantry placed new emphasis on dispersion and marksmanship; cavalry improved their dismounted work and reconnaissance skills; and artillery adopted methods of concealment and strove to improve accuracy and co-ordination. Across the army as a whole, the experience of combat lead to an overall downgrading of the importance of drill and obedience, replacing it instead with tactical skill and individual initiative. In addition, the thesis also examines the impact of the Boer War upon overall British Army doctrine and ethos. The process of reform prior to the First World War was marked by wide ranging debates upon the value of the South African experience, and not all lessons drawn from the conflict endured, with tactical restructuring being further complicated by changes of government and financial restrictions. Nevertheless, key lessons such as dispersion, marksmanship, concealment and firepower were ultimately retained and proved to be of great value during initial clashes against the Germans in 1914. Additionally, the Boer War caused the British to place new emphasis upon overall training of the individual, allowing advanced tactical skills to be inculcated more easily than had been possible in earlier years. However, the short duration of the conventional period of the Boer War meant that there was less opportunity to derive operational lessons for future employment. Furthermore, the colonial policing role of the British Army and the likelihood of small scale deployments meant that developing an operational doctrine was of less immediate value than ensuring flexibility and tactical skill. This meant that the British Army took a somewhat skewed developmental path in the 1902 – 1914. The process of reform ultimately produced a highly adaptable force that was tactically skilled, but which was ill-prepared for the operational complications posed by large scale deployment. While the Boer War was the principal factor in driving reform during the 1902 – 1914 period, there were additional influences at work, including examples from the Russo-Japanese War 1904 – 1905 and various ideas drawn from the armies of the continent. However, this thesis argues that while these outside influences contributed to ongoing debate, they did not offer any particular fresh ideas and were therefore of less importance than the Boer War in shaping British Army development.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Diagnosis of Secondary Source of Right-to-Left Shunt With Balloon Occlusion of Patent Foramen Ovale and Power M-Mode Transcranial Doppler

ObjectivesWe sought to assess the prevalence of secondary right-to-left circulatory shunt (RLS) in patients undergoing transcatheter closure of patent foramen ovale (PFO) as detected by power M-mode transcranial Doppler (TCD) and intracardiac echocardiography.BackgroundPrevalence of residual RLS in late follow-up after PFO closure may be as high as 34%. Other cardiac and noncardiac sources of RLS may coexist and obscure PFO closure evaluation.MethodsEighty-eight patients who underwent transcatheter PFO closure to prevent recurrent paradoxical cerebral embolism between June 2005 and December 2006 were evaluated for a secondary source of RLS. Before device deployment, a sizing balloon was inflated in the PFO tunnel and agitated saline contrast was injected into the inferior vena cava. Clinically significant secondary RLS was defined as >10 embolic tracks on TCD at rest or immediately after calibrated (40 mm Hg), sustained (10 s) respiratory strain, with corresponding negative color-flow Doppler. Late residual RLS was evaluated in all patients with TCD and transthoracic echocardiography (mean: 192 days; 95% confidence interval [CI]: 161 to 223 days).ResultsThe sample (n = 84) was 59% female, age 49 ± 14 years. Seventeen patients (20%; 95% CI: 11.7 to 28.8) had secondary RLS during balloon occlusion. At late follow-up (n = 66), 13 of 14 (93%) patients with secondary RLS and 23 of 52 (44%) patients without secondary RLS had residual RLS (p = 0.002).ConclusionsThis is the first report to systematically assess the prevalence of secondary RLS in patients undergoing PFO closure. Residual RLS detected by TCD may be due to secondary RLS, which may have implications for clinical outcomes

CAMAU Project: Progression Frameworks and Progression Steps

This paper contains information which provides a context for the work of the CAMAU research team based in the Universities of Glasgow and of Wales Trinity Saint David. This information includes an outline of the context of curriculum and assessment arrangements within which the research is situated and provides information on the processes of working with the Pioneer Schools network, a key aspect of the Welsh Government’s commitment to subsidiarity in educational decision making. This paper also includes key findings from the project’s Interim Report (October 2017) ‘Learning about Progression’