The morphology of cellular precipitation in aluminum rich aluminum-silver alloys

The morphology of cellular precipitation in Al-29.8wt%Ag alloy has been investigated in bulk specimens by transmission electron microscopy and in solution treated specimens by means of hot stage microscopy. Both cellular and general precipitation were observed to occur simultaneously in quench-aged and isothermally aged alloys. By studying the early stages of precipitation in the hot stage, the mechanism for the growth of cells in Al-Ag alloys was developed. According to this mechanism, the grain boundary allotriomorphs begin to form, the boundary then interacts with the allotriomorphs by bowing, and then either trailing precipitation forms on the allotriomorphs or new lamellae form at the advancing interface --Abstract, page iii

The Box and the Dark Night of the Soul: An Autoethnography from the Force of Losing a Child in the Delivery Room

From the perspective of parents who have lost children in labor and delivery rooms due to miscarriages, stillbirths, or who were born too early, the author argues that health care personnel including administrators, nurses, and doctors must be held accountable to the ethical responsibilities of caring for the parents of the children who have died. Based on the fact that administrators market their services to pregnant couples and promise to provide care, health care workers are ethically responsible to provide continued compassion

Revisiting summer infertility in the boar: impact of heat stress on the quality and DNA integrity of spermatozoa, and its mitigation by antioxidant therapy

Summer infertility in the pig continues to affect both productivity and profitability among pig producers in tropical and subtropical regions, with losses due to heat stress amounting to at least $300 million per year in the US swine industry alone. Given the wide scale production of pork globally, with at least five tropical countries among the top producers in the world, there is a need to revisit the problem of summer infertility in the pig and identify putative boar factors likely to contribute to poor reproductive performance during periods of heat stress. An important endpoint with this approach is to improve boar management practices and develop strategies to mitigate summer infertility in the pig. While the scrotum, pampiniform plexus, and cremaster and dartos muscles in mammals are specific adaptations to ensure sperm production in a regulated environment 4-6 °C below body temperature, the boar's inefficient capacity to sweat, non-pendulous scrotum, and low antioxidant activity in the semen, can make the it particularly vulnerable to the effects of heat stress. In Chapter 2, we demonstrated for the first time the link between summer heat stress and sperm DNA damage in Large White boars. Boars raised in the dry tropics of Townsville, Queensland, Australia during summer (peak wet) showed 16-fold more sperm DNA damage than early dry (cool and dry), and nearly 9-fold more than the late dry (warm and humid) season, respectively. Sperm concentration also decreased significantly in the peak wet. Sperm DNA damage has been previously demonstrated to contribute to early embryonic death in the mouse, and this magnitude of fragmentation is known to cause a reduction in litter size in sows. These findings provide impetus for the evaluation of sperm DNA integrity in commercial boar herds housed in the tropics as a putative contributing factor to seasonal infertility in the sow. While cryopreservation of boar spermatozoa is not widely practiced in commercial pig production, mostly due to reduced viability and fertilising capacity of post-thawed spermatozoa, it has a greater potential in advancing studies related to seasonal effects of heat stress on boar sperm fertility using in vitro fertilisation. Since the freeze-thaw process can led to increased sperm DNA damage and subsequently contribute to early embryo loss, in Chapter 3 we tried to address the limited information about the protective effects of the more common cryoprotectant glycerol on sperm DNA integrity during boar sperm cryopreservation. We aimed to determine the optimal concentration of glycerol to protect sperm DNA integrity, without the deleterious effect of high concentrations negatively affecting sperm motility. We deemed this work particularly important to permit us to freeze boar sperm collected during summer, for downstream use to fertilise eggs in vitro during winter when oocyte quality is high. Our study revealed that 3%, 6% or 8% glycerol could be safely used to cryopreserve boar spermatozoa without inducing additional DNA damage compared to fresh spermatozoa. We deemed a concentration of 6% glycerol provided the best DNA protection, while maintaining sufficient levels of sperm motility. In chapter 4, we aimed to develop reliable heat stress models that could be used at any time of the year, to advance the study of seasonal infertility in the pig by overcoming the variation and limitations associated with seasonal studies. We have successfully induced biologically meaningful levels of DNA damage in boar spermatozoa using either a whole animal in vivo model (hot room) or by direct exposure of semen to heat in vitro (heat shock model). However, we were only able to induce levels of damage observed during natural tropical summer (Chapter 2) using extreme in vitro temperatures that rendered boar spermatozoa completely immotile or dead. Here, our results suggest that boar sperm is vulnerable to heat-induced DNA damage, but individual factors may also contribute to a boar's overall susceptibility to heat stress. Given the limited endogenous levels of antioxidants in boar semen and the insufficient DNA repair mechanisms these cells have, Chapter 5 aimed to formulate and evaluate antioxidant therapy as a strategy to mitigate the effect of heat stress on boar sperm DNA integrity. We proposed that an exogenous multi-compound antioxidant supplementation could effectively combat heat stress induced oxidative damage and prevent the build-up of DNA fragmentation in boar spermatozoa. Supplementing boar diets with 100 g/day custom-mixed antioxidant during summer effectively reduced sperm DNA damage by as much as 55% after 42 and 84 days treatment, respectively. This implies that antioxidant supplementation during tropical summer could provide a measurable solution to the problem of boar-mediated summer infertility in the pig. Overall, boar sperm DNA integrity can be compromised during tropical summer and this can be induced experimentally using our in vivo or in vitro heat stress models; with response particularly affected by individual boar variability. Exogenous antioxidant supplementation in feed could provide an effective means to mitigate the problem of summer infertility. Apparently, neither seasonal heat stress or heat stress models negatively affected sperm motility, suggesting that traditional evaluation of sperm motility in boars may not detect inherently compromised DNA damage spermatozoa. Antioxidant supplementation only appears to mitigate DNA damage since it did not improve sperm motility or concentration after 42 or 84 days treatment. Future studies are needed to measure the beneficial impact of antioxidant supplementation under tropical farm conditions, in terms of improved sperm DNA integrity and increased litter size following artificial insemination

Biosecurity and readiness of smallholder pig farmers against potential African Swine Fever outbreak and other pig diseases in Baybay City, Leyte, Philippines

Preventing African Swine Fever (ASF) outbreaks require an active involvement of pig growers as they are in the frontline of detection, notification, and the application of strict biosecurity measures. The Eastern Visayas (Region VIII) in Central Philippines is still free of ASF but the risk can be remarkable given the high volume of pigs that enter in this region as a market hub to large pig producers both coming from Luzon (north) and Mindanao (south). This study was conducted to better understand the readiness and biosecurity practices of smallholder pig farmers who comprise most of the pig growers in the City of Baybay, Leyte. Using multiple correspondence analysis (MCA) and agglomerative hierarchical clustering (AHC) technique of data from 350 pig farmer-respondents, our study found several areas in pig raising activities that need to be highlighted. While pig farmers were generally aware of the threat posed by ASF and have relatively good biosecurity practices, only 32.90% were convinced that the City of Baybay is prepared in the case of an ASF outbreak. Moreover, the importance of vaccination, footbath, and controlling swill feeding need to be emphasized (Cluster 2, 58.29%).  More efforts should be directed towards preparing and training pig farmers on disease monitoring and surveillance and improving further its biosecurity practices with special focus on bioexclusion. Similar studies should be conducted to nearby local government units particularly those located near entry and exit borders of the Eastern Visayas region

Positive Psychological Transformation: A Mixed Methods Investigation Into Catalysts and Processes of Meaningful Change

This mixed methods study investigated the experience of positive psychological transformation, including its catalysts, dynamics, supportive factors, and outcomes. The first phase of the study was a 13-item survey (N=130) that revealed trends and associations in participants’ experiences of transformation. The most significant correlation was between “expressing myself” and change stabilization (p \u3c .01). Forty-four percent of participants reported trauma or emotional distress as the main catalyst of their transformation. Each of the other three main catalysts (dissonance, adaptation, and inspiration) drew approximately 18% of responses. Connecting with nature (71%), introspection (65%), solitude (63%) and empathy (61%) were commonly reported supportive factors. Common changes related to participants’ way of interacting with others (77%), perception (75%), and emotional patterns (70%). The process of transformation differed substantially depending on multiple factors including the catalyst and demographic categories. Additionally, the survey revealed a trend of moving away from organized religion toward a sense of being spiritual but not religious. The second phase of the study consisted of interviews with a portion of the participants who reported trauma as the main catalyst of their transformation (n = 26) and was focused on the experience of posttraumatic growth. Thematic analysis revealed that transformation is typically initiated by a series of traumatic events and that the process of transformation can involve impaired well-being/functioning before elevated well-being/functioning. The results of thematic analysis were consistent with existing data on posttraumatic growth

Positive Psychological Transformation: A Mixed Methods Investigation Into Catalysts and Processes of Meaningful Change

This mixed methods study investigated the experience of positive psychological transformation, including its catalysts, dynamics, supportive factors, and outcomes. The first phase of the study was a 13-item survey (N=130) that revealed trends and associations in participants’ experiences of transformation. The most significant correlation was between “expressing myself” and change stabilization (p \u3c .01). Forty-four percent of participants reported trauma or emotional distress as the main catalyst of their transformation. Each of the other three main catalysts (dissonance, adaptation, and inspiration) drew approximately 18% of responses. Connecting with nature (71%), introspection (65%), solitude (63%) and empathy (61%) were commonly reported supportive factors. Common changes related to participants’ way of interacting with others (77%), perception (75%), and emotional patterns (70%). The process of transformation differed substantially depending on multiple factors including the catalyst and demographic categories. Additionally, the survey revealed a trend of moving away from organized religion toward a sense of being spiritual but not religious. The second phase of the study consisted of interviews with a portion of the participants who reported trauma as the main catalyst of their transformation (n = 26) and was focused on the experience of posttraumatic growth. Thematic analysis revealed that transformation is typically initiated by a series of traumatic events and that the process of transformation can involve impaired well-being/functioning before elevated well-being/functioning. The results of thematic analysis were consistent with existing data on posttraumatic growth

The protoMIRAX Hard X-ray Imaging Balloon Experiment

The protoMIRAX hard X-ray imaging telescope is a balloon-borne experiment developed as a pathfinder for the MIRAX satellite mission. The experiment consists essentially in a coded-aperture hard X-ray (30-200 keV) imager with a square array (13$\times$13) of 2mm-thick planar CZT detectors with a total area of 169 cm$^2$. The total, fully-coded field-of-view is $21^{\circ}\times 21^{\circ}$ and the angular resolution is 1$^{\circ}$43'. In this paper we describe the protoMIRAX instrument and all the subsystems of its balloon gondola, and we show simulated results of the instrument performance. The main objective of protoMIRAX is to carry out imaging spectroscopy of selected bright sources to demonstrate the performance of a prototype of the MIRAX hard X-ray imager. Detailed background and imaging simulations have been performed for protoMIRAX balloon flights. The 3$\sigma$ sensitivity for the 30-200 keV range is ~1.9 $\times$ 10$^{-5}$ photons cm$^{-2}$ s$^{-1}$ for an integration time of 8 hs at an atmospheric depth of 2.7 g cm$^{-2}$ and an average zenith angle of 30$^{\circ}$. We have developed an attitude control system for the balloon gondola and new data handling and ground systems that also include prototypes for the MIRAX satellite. We present the results of Monte Carlo simulations of the camera response at balloon altitudes, showing the expected background level and the detailed sensitivity of protoMIRAX. We also present the results of imaging simulations of the Crab region. The results show that protoMIRAX is capable of making spectral and imaging observations of bright hard X-ray source fields. Furthermore, the balloon observations will carry out very important tests and demonstrations of MIRAX hardware and software in a near space environment.Comment: 9 pages, 13 figures, accepted for publication in Astronomy & Astrophysic

High dispersal ability inhibits speciation in a continental radiation of passerine birds

Dispersal can stimulate speciation byfacilitating geographical expansion across barriers or inhibit speciation by maintaining gene flow among populations. Therefore, the relationship between dispersal ability and speciation rates can be positive or negative. Furthermore, an \u27intermediate dispersal\u27 model that combines positive and negative effects predicts a unimodal relationship between dispersal and diversification. Because both dispersal ability and speciation rates are difficult to quantify, empirical evidence for the relationship between dispersal and diversification remains scarce. Using a surrogate for flight performance and a species-level DNA-based phylogeny of a large South American bird radiation (the Furnariidae), we found that lineages with higher dispersal ability experienced lower speciation rates. We propose that the degree of fragmentation or permeability of the geographical setting together with the intermediate dispersal model are crucial in reconciling previous, often contradictory findings regarding the relationship between dispersal and diversification. © 2011 The Royal Society

Population genomics of rapidly invading lionfish in the Caribbean reveals signals of range expansion in the absence of spatial population structure.

© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Bors, E. K., Herrera, S., Morris, J. A., Jr., & Shank, T. M. Population genomics of rapidly invading lionfish in the Caribbean reveals signals of range expansion in the absence of spatial population structure. Ecology and Evolution, 9(6), (2019):3306-3320, doi:10.1002/ece3.4952.Range expansions driven by global change and species invasions may have significant genomic, evolutionary, and ecological implications. During range expansions, strong genetic drift characterized by repeated founder events can result in decreased genetic diversity with increased distance from the center of the historic range, or the point of invasion. The invasion of the Indo‐Pacific lionfish, Pterois volitans, into waters off the US East Coast, Gulf of Mexico, and Caribbean Sea provides a natural system to study rapid range expansion in an invasive marine fish with high dispersal capabilities. We report results from 12,759 single nucleotide polymorphism loci sequenced by restriction enzyme‐associated DNA sequencing for nine P. volitans sampling areas in the invaded range, including Florida and other sites throughout the Caribbean, as well as mitochondrial control region D‐loop data. Analyses revealed low to no spatially explicit metapopulation genetic structure, which is partly consistent with previous finding of little structure within ocean basins, but partly divergent from initial reports of between‐basin structure. Genetic diversity, however, was not homogeneous across all sampled sites. Patterns of genetic diversity correlate with invasion pathway. Observed heterozygosity, averaged across all loci within a population, decreases with distance from Florida while expected heterozygosity is mostly constant in sampled populations, indicating population genetic disequilibrium correlated with distance from the point of invasion. Using an FST outlier analysis and a Bayesian environmental correlation analysis, we identified 256 and 616 loci, respectively, that could be experiencing selection or genetic drift. Of these, 24 loci were shared between the two methods.We thank the many participants of the Gulf and Caribbean Fisheries Institute for providing lionfish samples from around the Caribbean region, as well as Dr. Bernard Castillo at the University of the Virgin Islands and Kristian Rogers at the Biscayne Bay National Park. We would like to acknowledge Alex Bogdanoff at NOAA, Beaufort NC, for assistance with sample acquisition; Camrin Braun at WHOI, for assistance with the calculation of oceanic distances between sites; Dr. Tom Schultz at Duke Marine Lab and Dr. Margaret Hunter at USGS for discussions concerning ongoing population genetic projects; and Jack Cook at the WHOI Graphics department for his assistance in generating maps of the study area. We would like to extend a special thank you to Dr. John Wakeley of Harvard University for assistance in the interpretation of data. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. 1122374. Sequencing funding was provided in part by the PADI Foundation Grant No. 14904. Additional research support was provided by the Woods Hole Oceanographic Institution (WHOI) Ocean Ventures Fund, the Coastal Ocean Institute at WHOI, the National Science Foundation (OCE‐1131620 to TMS), and the James Education Fund for Ocean Exploration within the Ocean Exploration Institute at WHOI. Publication of this paper was supported, in part, by the Henry Mastin Graduate Student Fund administered by the Oregon State University Department of Fisheries and Wildlife. Finally, we sincerely thank the reviewers and editors who helped to strengthen this manuscript

Changing times and agrarian unrest in Nueva Ecija: The breakdown of share tenancy in a Philippine province during the early twentieth century

The early twentieth century was a time of tremendous change for the Philippines when American rule,liberal democracy and capitalism, introduced a generation of Filipinos to a new world.As they navigated their way through the era they faced new sets of challenges. While some practices were reconciled with the modern ways, others had to yield to changing times.Among those affected was the relationship of landlords and their share tenants.In Nueva Ecija, a province in Central Luzon, while internal defects of share tenancy already caused landlord-tenant relations to deteriorate, external factors added pressure to the already volatile situation.These factors were: economic instability, consumerism, pricecontrol, open government support to peasants, class consciousness and labor leaders.The paper shall evaluate the confluence of the defects of share tenancy and the external factors that led to agrarian unrest in the province during the prewar era.It will also assess the impact of changing times on landlordism in the Philippines