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Assessing species status and genetic diversity in the Tombigbee Darter (Etheostoma lachneri)
No full textThe Tombigbee Darter (Etheostoma lachneri) is the sole member of the snubnose subgenus Ulocentra endemic to the Tombigbee River Watershed of Mississippi and Alabama. Etheostoma lachneri is a species of greatest conservation need, due to suspected population decline since 1994 (Suttkus et al., 1994). To assess the persistence and genetic variability of E. lachneri, a population survey at 40 historical sites in Mississippi was performed. Results showed that 12 out of the 40 sites did not have E. lachneri present. Genomic analyses were conducted for populations across the species range using ddRADseq, revealing the possible complex of three species. To assess environmental DNA (eDNA) detection, E. lachneri mitogenome was sequenced. Results showed that E. lachneri eDNA was present at 10 of 39 survey sites but was less accurate than traditional sampling. Results presented here will contribute to the prioritization of E. lachneri in the Mississippi and Alabama statewide action plans
In good times & bad: measuring ambivalence in custodial grandparents
No full textLike other forms of caregivers, custodial grandparents experience both the joys and trials of raising their grandchildren. This culmination of positive and negative feelings is called “caregiver ambivalence. It has only recently been studied in relation to caregiver burden and wellness in the form of caregiver ambivalence theory (CAT). By collecting data from approximately 395 custodial grandparents via an online survey, the current study aimed to test if custodial grandparents’ feelings of burden influence their perceived well-being and if feelings of ambivalence mediate this relation. Implications of this research include identifying areas of strength and growth within custodial grandparents and facilitating the development of supports for custodial grandparents and their families
Missing data in agriculture and survival studies
No full textThis dissertation explored two missing data problems in statistical analysis arising from imbalance in agricultural research and censoring in survival studies. The first research was inspired by the U.S. National Cotton Variety Test trial, where the trial data are imbalanced because only a subset of varieties is selected for the following year. We simulated selection processes that differ from the existing literature and offer four main contributions. First, we adopted a joint modeling framework that utilizes a logistic regression to generate data that follow missing completely at random, missing at random, or missing not at random (MNAR). Second, our selection depends on multiple traits, whereas all existing studies used a single trait for selection. Third, besides variance components (VC), we studied 30-year long-term genetic and non-genetic trends. Last, we evaluated prediction accuracy for variety’s overall and location-specific performance. Results show that the VC and long-term trends estimations are the worst under MNAR using the single trait for selection. Compared to VC, the long-term trends estimation is more influenced by missing mechanism and rate. Prediction accuracy for variety’s performance is mainly driven by the missing rate and is less sensitive to the selection process. Ignoring the genetic and non-genetic long-term trends deteriorates both estimation and prediction, whereas adding more testing years improves them despite higher missingness. The second research addresses censored clustered survival data by developing two multiple imputation (MI) strategies within a copula framework. A marginal MI method imputes censored times based solely on covariates, whereas conditional MI approaches also utilize dependency between paired event times through a risk score framework. Both strategies apply Nearest Neighbor (NN) and Kernel Smoothing (KS) algorithms for imputing risk sets, and subsequent analysis performs Two-Stage Pseudo Maximum Likelihood Estimation (PMLE). Simulations across censoring levels, cluster sizes, and dependence strengths reveal that MI enhances the accuracy of marginal regression coefficient estimates but not copula parameter estimation. NN-based imputation outperforms KS, and frailty-adjusted MI with NN demonstrates robustness to copula-frailty misspecification. Marginal MI with NN is recommended for marginal targets; direct copula modeling via Two-Stage PMLE is preferred for dependence structures focused analyses
Train Engine No. 638in Water Valley, Mississippi, October 31, 1893
No full textCasey Jones is pictures in the cabin of train engine number 630 of the Illinois Central Railroad Company, a consolidation 280 engine that Jones ran from the World\u27s Columbian Exposition in Chicago, Illinois to Water Valley, Mississippi in October 1893. Another man is pictured standing on the steps of the engine and trees are seen behind the engine. A typed note on the back of the photograph tells the story of Jones\u27 trip and the impressive feat of running the engine over five operating divisions. A red ink stamp advertising Jay\u27s Caboose in Greensboro, Alabama is beneath the note.https://scholarsjunction.msstate.edu/mss-lampton-images-ms-delta/1348/thumbnail.jp
The Church of the Redeemer, Biloxi, Mississippi
No full textThis postcard features a color illustration of the Church of the Redeemer in Biloxi, Mississippi, a one story building with a short bell tower with a cross at the peak and a gabled roof. Trees draped with Spanish moss are on the lawn in front of the church. A bench is depicted between two of the threes to the left of the church. The title of the card is printed along the bottom edge of the card.https://scholarsjunction.msstate.edu/mss-lampton-images-ms-coast/1746/thumbnail.jp
Great Southern Hotel, The Aristocrat of Southern Taverns, Gulfport, Mississippi
No full textA color illustration of the Great Southern Hotel in Gulfport, Mississippi is featured on this postcard. The hotel is a large, four story, L-shaped structure with balconies along the second floor of the shorter portion of the building, dormer windows long the roof, and is depicted as having green siding with a red roof. Lust bushes and trees dot the hotel grounds, a long sidewalk is depicted in front of the hotel. The title along the bottom of the card claims the hotel to be the Aristocrat of Southern Taverns.https://scholarsjunction.msstate.edu/mss-lampton-images-ms-coast/1759/thumbnail.jp
Hotel Avelez, Biloxi, Mississippi
No full textA sepia toned image of the Hotel Avelez in Biloxi, Mississippi, a five story hotel with Spanish architectural influence is featured on this postcard along with the image of two small sailboats on the water. The title of the card is printed along the bottom edge of the card and an advertisement for the hotel is printed in the upper left of the back of the card.https://scholarsjunction.msstate.edu/mss-lampton-images-ms-coast/1767/thumbnail.jp
Belhaven College, Jackson, Mississippi
Get PDFA large, two story building with a cupola and a two covered porches and a smaller two story building with a chimney and a covered porch on the Belhaven College campus is featured in this color postcard. Trees and an expanse of green lawn is seen around and in front of the buildings. The title of the card is printed in red in the upper right edge of the card.https://scholarsjunction.msstate.edu/mss-lampton-images-ms-capitol/1509/thumbnail.jp
Mississippi State Bank, Canton, Mississippi
Get PDFA color illustration of the Mississippi State Bank in Canton, Mississippi, a two story, red brick corner building with arched windows on the bottom floor is featured on this postcard. A person is depicted walking into the building. Foral details boarder the image on each end. The title of the card is printed in red along the upper left.https://scholarsjunction.msstate.edu/mss-lampton-images-ms-capitol/1519/thumbnail.jp
Mansion and Ballard Building, Tougaloo University, Tougaloo, Mississippi
Get PDFA color image of The Mansion (Robert O. Wilder Building) and the Ballard Building at Tougaloo University in Tougaloo, Mississippi is featured on this postcard. The mansion on the left is a three level building with dentil molding along the rooflines and arched windows on the top level and a lush, leafy tree obscuring the left corner of the building. The Ballard Building to the right is a two story building with trees growing in front of and beside it. the title of the card is printed in red along the top of the image.https://scholarsjunction.msstate.edu/mss-lampton-images-ms-capitol/1526/thumbnail.jp