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Radionuclide imaging plays a critical role in the diagnosis and management of kidney obstruction. However, most practicing radiologists in US hospitals have insufficient time and resources to acquire training and experience needed to interpret radionuclide images, leading to increased diagnostic errors. To tackle this problem, Emory University embarked on a study that aims to develop a computer-assisted diagnostic (CAD) tool for kidney obstruction by mining and analyzing patient data comprised of renogram curves, ordinal expert ratings on the obstruction status, pharmacokinetic variables, and demographic information. The major challenges here are the heterogeneity in data modes and the lack of gold standard for determining kidney obstruction. In this article, we develop a statistically principled CAD tool based on an integrative latent class model that leverages heterogeneous data modalities available for each patient to provide accurate prediction of kidney obstruction. Our integrative model consists of three sub-models (multilevel functional latent factor regression model, probit scalar-on-function regression model, and Gaussian mixture model), each of which is tailored to the specific data mode and depends on the unknown obstruction status (latent class). An efficient MCMC algorithm is developed to train the model and predict kidney obstruction with associated uncertainty. Extensive simulations are conducted to evaluate the performance of the proposed method. An application to an Emory renal study demonstrates the usefulness of our model as a CAD tool for kidney obstruction. [ABSTRACT FROM AUTHOR]

As taxonomic studies revise our understanding of biodiversity, both fisheries managers and the angling public must adapt to best conserve fisheries. Unfortunately, communication gaps between scientists and anglers may result in lags and inaccuracies in the taxonomic information available to anglers. We updated the International Game Fish Association (IGFA)'s black bass Micropterus spp. world records to current taxonomic consensus. Seven new species were acknowledged for all‐tackle world record availability, and four of seven existing species records were revised. Florida Bass M. salmoides (formerly M. floridanus), Neosho Bass M. velox, and four members of the Redeye Bass species complex (M. cahabae, M. chattahoochae, M. tallapoosae, and M. warriorensis) are now recognized. Additionally, Alabama Bass M. henshalli—an emerging invasive species—is now distinguished from the smaller, broadly distributed Spotted Bass M. punctulatus. A misidentified specimen resulted in vacant all‐tackle records for Shoal Bass M. cataractae and Redeye Bass M. coosae. Genetic verification is warranted in the future, but implementation may create accessibility barriers to record submissions. We hope these efforts will encourage anglers to learn more about black bass diversity, to pursue their own world record catches, and to gain awareness of the conservation challenges threatening this iconic group. [ABSTRACT FROM AUTHOR]

Objective: The Yaqui Catfish Ictalurus pricei, a species that is endemic to the southwestern United States and west‐central Chihuahua and Sonora, Mexico, is extinct in the United States and extremely endangered in Mexico due to habitat loss and hybridization with nonnative Channel Catfish I. punctatus. To re‐establish populations in the United States, a binational program consisting of broodstock collection, fish propagation, stocking, and poststocking monitoring is necessary. This programmatic approach is encapsulated within a Conservation Propagation and Stocking Program (CPSP), which documents important recovery actions, such as genetic management, fish culture, stocking, and poststocking assessments. The focus of our work is to identify the optimal stocking strategy for Yaqui Catfish, thereby informing the framework of a CPSP for the species' recovery. Methods: Our strategy involved simulating population growth using an age‐structured simulation model with varying stocking contribution rates, stocking densities, and stocking frequencies and incorporating these biological data with economic information within a utility function to quantify stocking costs. Result: The optimal strategy requires releasing Yaqui Catfish at a density of 200 fish/ha every 5 years. This strategy excludes natural recruitment because historically, stocked Yaqui Catfish inhabited waters that were either too small or devoid of habitat to induce natural spawning. However, if larger waters or waters having appropriate habitats (e.g., interstitial spaces) are also stocked, it should increase natural recruitment, thereby (1) enabling populations to become self‐sustaining and (2) drastically reducing the reliance on hatcheries for stocking and salvage of declining populations. Conclusion: Our results provide important stocking recommendations within a CPSP, emphasizing the need to build a broodstock before genetically pure Yaqui Catfish disappear. The successful implementation of the optimal stocking strategy requires multiple locations for stocking fish and is contingent on strengthening binational partnerships. This approach fills an important void in Yaqui Catfish reestablishment, helping to prime the successful recovery of this species. Impact statementThe Yaqui Catfish, once native to regions of the United States and Mexico, faces near extinction due to habitat degradation and nonnative hybridization. A binational Conservation Propagation and Stocking Program offers a promising solution, suggesting for the release of 200 fish per hectare every 5 years in the United States. The initiatives success, however, hinges on using multiple stocking locations in Mexico and bolstering binational collaboration. [ABSTRACT FROM AUTHOR]

The Neosho Bass (Micropterus velox), a former subspecies of the keystone top‐predator and globally popular Smallmouth Bass (M. dolomieu), is endemic and narrowly restricted to small, clear streams of the Arkansas River Basin in the Central Interior Highlands (CIH) ecoregion, USA. Previous studies have detected some morphological, genetic, and genomic differentiation between the Neosho and Smallmouth Basses; however, the extent of neutral and adaptive divergence and patterns of intraspecific diversity are poorly understood. Furthermore, lineage diversification has likely been impacted by gene flow in some Neosho populations, which may be due to a combination of natural biogeographic processes and anthropogenic introductions. We assessed: (1) lineage divergence, (2) local directional selection (adaptive divergence), and (3) demographic history among Smallmouth Bass populations in the CIH using population genomic analyses of 50,828 single‐nucleotide polymorphisms (SNPs) obtained through ddRAD‐seq. Neosho and Smallmouth Bass formed monophyletic clades with 100% bootstrap support. We identified two major lineages within each species. We discovered six Neosho Bass populations (two nonadmixed and four admixed) and three nonadmixed Smallmouth Bass populations. We detected 29 SNPs putatively under directional selection in the Neosho range, suggesting populations may be locally adapted. Two populations were admixed via recent asymmetric secondary contact, perhaps after anthropogenic introduction. Two other populations were likely admixed via combinations of ancient and recent processes. These species comprise independently evolving lineages, some having experienced historical and natural admixture. These results may be critical for management of Neosho Bass as a distinct species and may aid in the conservation of other species with complex biogeographic histories. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of Re complexes, which are used for interpreting the nature of tracer [super 99m]Tc radiopharmaceuticals, are described. The chemistry of Re analogues with [LAN.sup.2-]are used for designing new small agents and tagging large agents because two uncoordinated carboxyl groups are available for conjugation with biological molecules such as proteins.

A study was conducted on the coordination capabilities of ligands (ENDACH2 and ENACH) with aliphatic amines as the only nitrogen donors toward the fac-{M(CO)3} core. Tridentate ligation was observed when two sp(super 3) nitrogen donors and at least one sp(super 3) carboxyl oxygen donor were available.

Research has been conducted on the radiopharmaceuticals. The factors leading to one isomeric species in one ionization state at physiological pH are analyzed.

Angler tag‐return studies are a cornerstone of fisheries research, providing insights into individual movements and estimates of exploitation, among many other applications. However, the data generated from these studies is dependent upon effective communication between anglers and scientists. As technological advances are adopted by anglers, little research has been directed at the potential benefits of incorporating modern tag reporting methods. We tagged stream‐dwelling black bass Micropterus spp. and provided anglers a choice of reporting methods (telephone, email, iNaturalist app, or a "mixed‐mode" combination thereof). Our objectives were to examine the fate of reported fish, quantify trends in data quality across reporting methods, and explore how geographic location and angler avidity may influence use of reporting methods. Ninety‐four percent of tag reports involved the release of the fish with the tag still intact, creating opportunities for longer‐term data collection. Telephone was the most commonly used reporting method; however, this method had significantly lower completeness scores (e.g., lack of photographs or specifying fate of fish) and less precise location information than other methods. In contrast, iNaturalist had the highest completeness and most precise location information but was seldom used and had increased lag times in reporting. We found no significant differences in the proportion of reporting methods used across stream locations in our study, and avid anglers appeared to be individualistic in their choice of method. Overall, our study suggests that the adoption of modern reporting methods, like email and smartphone apps, could benefit data collection efforts of angler tag‐return studies. Fisheries scientists may wish to consider which reporting methods align with their specific study objectives and with the angling public of a given study area. [ABSTRACT FROM AUTHOR]

The Yaqui Catfish Ictalurus pricei is an understudied species, with limited information available on its ecology, distribution, and local habitat use. Native to the southwestern United States and northwestern Mexico, Yaqui Catfish populations are declining, which has prompted listing of the species as threatened in the United States and as a species of concern in Mexico. Water overallocation, habitat degradation, invasive species introductions, and hybridization with nonnative Channel Catfish I. punctatus have caused the populations in Mexico to decline. The United States population collapsed after years of low recruitment. To better focus conservation efforts as well as define habitat associated with Yaqui Catfish occurrences, we assessed the distribution in the Yaqui River basin of Mexico by using historical data at a landscape scale. Yaqui Catfish were historically found across the watershed among a diversity of environments but were most frequently associated with small, intermittent streams. Basin land cover was dominated by forest, shrubland, and grassland, and Yaqui Catfish generally occurred in stream segments at similar proportions. However, a small number of Yaqui Catfish occurrences were associated with urban and cropland land cover types in proportions greater than the availability of those categories on the landscape. With the species facing declines in the region, this work will help to inform future conservation efforts aimed at securing the Yaqui Catfish, protecting suitable habitat, and better defining its current status in Mexico. [ABSTRACT FROM AUTHOR]

Water temperature is an important abiotic factor that impacts physiological processes in fish. Attempts to quantify thermal tolerance of fishes exposed to various temperatures have been performed since the 1800s. A common approach to test the thermal tolerance of fishes is the critical thermal method. Traditionally this method has required access to large and expensive lab equipment. However, many individuals may not have direct access to such equipment, making critical thermal studies difficult‐to‐impossible to conduct. We present a simple and cost‐friendly alternative device to use for critical thermal minima trials. This device uses a cooler with a copper line and copper coil to chill water within an aquarium. A pump and valves control the water flow as it passes from the aquarium through the copper. This allows the user to lower the water temperature in the aquarium from 28oC to 0oC at a steady rate of 0.23oC min−1. The device allows those with limited funding or without access to traditional lab equipment the ability to perform critical thermal minima trials, expanding our collective understanding of life histories of fish and their potential vulnerabilities to increasingly altered thermal environments. [ABSTRACT FROM AUTHOR]

Summary: Water temperature controls a plethora of morphological and metabolic functions in fishes and studies examining thermal tolerance of fishes and the responses of fishes to changing water temperatures have been conducted for over a century. Although there has been a renewed interest in the management and conservation of alligator gar, currently there are no data regarding the thermal minima of the species. In this study, we obtained alligator gar juveniles from a hatchery setting, acclimated these fish to three separate water temperatures (21, 24.5, and 28°C) and then subjected them to critical thermal minima trials to quantify lower thermal tolerance. Critical thermal minima results were found to be related with acclimation temperature and total length. Less developed gar experienced equilibrium loss at higher temperatures than larger, more developed gar. Also, alligator gar in the coldest acclimation trials (21°C) were able to tolerate the lowest temperatures. The mean CTmin temperature values obtained for each acclimation trial were 11.57°C, SD = 1.39 (21°C), 12.83°C, SD = 1.47 (24.5°C), and 14.16°C, SD = 1.60 (28°C). This study helps to fill an important data gap in alligator gar life history, and our results could be beneficial for management of alligator gar and determining potential future range distributions. [ABSTRACT FROM AUTHOR]

Fishing in streams and rivers is a popular outdoor recreation activity in eastern Oklahoma, where most anglers target black bass (Micropterus) species. Since the early 1990s, when the last assessment of black bass fishing in the region was conducted, broadscale factors such as harvesting behavior, state fishery regulations, and bass population dynamics have changed. In 2018, we conducted creel and fish tagging surveys in three tributaries of Lake Tenkiller (Caney Creek, Baron Fork, and Illinois River) that differed in size and accessibility to provide current estimates of catch, harvest, and effort directed toward black bass. We then related these estimates to angler socioeconomic characteristics. The amount of angler effort was concomitant with stream size and accessibility, being greatest in the largest stream with the most access (Illinois River). However, catch rates were highest in the medium‐sized stream (Baron Fork). Harvest rates and exploitation were near zero in all systems. Anglers fishing Caney Creek, the smallest and least accessible stream, were nearly all local, coming from zip codes ~42 km away, with low median household incomes compared to anglers at the other streams who came from a broader array of more distant zip codes and had higher median household incomes. Anglers fishing the smallest stream were also more interested in harvesting fish and having higher creel limits than anglers at the other two systems. In the Oklahoma Ozark Highlands, stream size and accessibility appear to be a significant factor in angler demographics, potentially necessitating different management strategies. [ABSTRACT FROM AUTHOR]

The first reported invasion of Asian swamp eels (Monopterus albus, ASE) in the continental United States was in the state of Georgia in 1994. This population was first discovered within several ponds on a private nature centre, but the ponds drained via an outflow pipe into marsh habitats along the Chattahoochee River. Our objective was to delineate the current invasion extent of ASE in the Chattahoochee River, Georgia, by sampling juvenile ASE within an occupancy modelling framework. We sampled 111 and 100 sites in 2015 and 2016 respectively, on 10 occasions, each within a 2-km radius of the purported invasion point to estimate the spatial extent of their invasion in this system. Leaf-litter traps (LLTs) were effective at documenting an increase in the invasion extent of ASE, from within 100 m of the Chattahoochee Nature Center pond outflow to 1.6 km away. Documenting the extent of invasion of this population has proven elusive in the past, but the use of LLTs to target juvenile eels has documented a larger invasion extent than previously known in the study system. The results of this research can be used to develop effective control and management strategies, such as locating potential breeding areas for targeted removal sampling. [ABSTRACT FROM AUTHOR]

Purpose: 99mTc-tricarbonyl-nitrilotriacetic acid, [99mTc]Tc(CO)3(NTA), is a new 99mTc-renal radiopharmaceutical with a clearance equal to that of 131I-ortho-iodohippuran, [131I]I-OIH. Our purpose was to compare the performance of [99mTc]Tc(CO)3(NTA) and [99mTc]Tc-MAG3 in patients with suspected obstruction. Methods: [99mTc]Tc(CO)3(NTA) was prepared with commercially available NTA ligand and CRS Isolink kit, and isolated by HPLC. Eighteen adult patients referred for diuretic renography received an intravenous injection of approximately 40 mg of furosemide 15 min prior to either [99mTc]Tc(CO)3(NTA) or [99mTc]Tc-MAG3 (mean activity of 47 ± 4.4 MBq). Data were acquired for 24 min followed by an anterior image of the liver and gall bladder and a measure of voided volume. Patients received a second furosemide injection equal to one third of the original dose followed fifteen minutes later by administration of the alternate tracer, mean activity of 320 ± 34 MBq. Clearances were measured using a camera-based technique. Results: The clearance of NTA was greater than that of MAG3, 331 ± 146 versus 271 ± 105 mL/min/1.73 m2, respectively, p < 0.0001. The kidney to background ratio for NTA was greater than that of MAG3 for both left and right kidneys, p < 0.001; the 20 min/maximum count ratio was significantly less, p < 0.0001. There was no significant difference in the voiding volumes following NTA and MAG3 administration, 598 ± 237 mL versus 498 ± 170 mL, respectively, p = 0.07. Gall bladder activity was not observed with NTA but was present in 6/17 MAG3 studies. Images and renogram curves were comparable except for two patients where the NTA study excluded obstruction but the MAG3 study suggested an indeterminate or obstructed kidney. Conclusions: Unlike MAG3, NTA is not eliminated via the hepatobiliary track. Moreover, NTA has a higher kidney to background ratio and more rapid clearance than MAG3. These advantages should allow more robust camera-based clearance measurements and may lead to better discrimination between obstructed and non-obstructed kidneys. [ABSTRACT FROM AUTHOR]

Kidney obstruction, if untreated in a timely manner, can lead to irreversible loss of renal function. A widely used technology for evaluations of kidneys with suspected obstruction is diuresis renography. However, it is generally very challenging for radiologists who typically interpret renography data in practice to build high level of competency due to the low volume of renography studies and insufficient training. Another challenge is that there is currently no gold standard for detection of kidney obstruction. Seeking to develop a computer-aided diagnostic (CAD) tool that can assist practicing radiologists to reduce errors in the interpretation of kidney obstruction, a recent study collected data from diuresis renography, interpretations on the renography data from highly experienced nuclear medicine experts as well as clinical data. To achieve the objective, we develop a statistical model that can be used as a CAD tool for assisting radiologists in kidney interpretation. We use a Bayesian latent class modeling approach for predicting kidney obstruction through the integrative analysis of time-series renogram data, expert ratings, and clinical variables. A nonparametric Bayesian latent factor regression approach is adopted for modeling renogram curves in which the coefficients of the basis functions are parameterized via the factor loadings dependent on the latent disease status and the extended latent factors that can also adjust for clinical variables. A hierarchical probit model is used for expert ratings, allowing for training with rating data from multiple experts while predicting with at most one expert, which makes the proposed model operable in practice. An efficient MCMC algorithm is developed to train the model and predict kidney obstruction with associated uncertainty. We demonstrate the superiority of the proposed method over several existing methods through extensive simulations. Analysis of the renal study also lends support to the usefulness of our model as a CAD tool to assist less experienced radiologists in the field. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]

The Alligator Gar Atractosteus spatula (AG) is a long‐lived fish of growing management and conservation interest. Situated on the border of Texas and Oklahoma, Lake Texoma supports one of the last robust AG populations in Oklahoma; however, a genetic evaluation of this population is lacking. We genotyped AG individuals with 17 microsatellite loci, 7 of which also cross‐amplified in three sympatric Lepisosteus species: the Longnose Gar L. osseus (LN), Shortnose Gar L. platostomus (SN), and Spotted Gar L. oculatus (SP). Bayesian assignment analyses conducted in STRUCTURE and NewHybrids confirmed that a field‐identified hybrid was an F1 AG × LN and identified five other individuals that were suspected backcrosses (three LN × SN; two SN × SP). Alligator Gar had the lowest observed heterozygosity (0.179) and the lowest allelic richness (1.682) among the nonhybrid individuals of the four gar species examined. We also examined the potential for population structure and differences in pairwise relatedness (r) between two areas where AG are commonly encountered within Lake Texoma: the Red River and Washita River arms. No population structure was detected using noninformative or location priors in STRUCTURE, and estimates of r produced by the TrioML estimator in COANCESTRY were not significantly different between arms (overall mean r = 0.199). Point estimates of effective population size ranging from 16.3 to 29.2 suggested that the AG population may be vulnerable to the effects of inbreeding depression and random genetic drift. Results provide a genetic status assessment of AG in Lake Texoma and a baseline for future management and conservation decisions within Lake Texoma and surrounding regions. [ABSTRACT FROM AUTHOR]

Re(CO)3 complexes with tridentately coordinated alpha-amino acids bearing a thioether group is synthesized by using a new strategy for preparing solution of the fac-[Re(CO)3(H2O)3]+ precursor analogues to the solutions for preparing (super 99m)Tc radiopharmaceuticals. The latter generates an asymmetric center, and NMR and X-ray methods provided evidence for the formation of both possible diastereoisomers, which interchange rapidly in solution except when the thioether has an appended acetate group.

Leveraging existing presence records and geospatial datasets, species distribution modeling has been widely applied to informing species conservation and restoration efforts. Maxent is one of the most popular modeling algorithms, yet recent research has demonstrated Maxent models are vulnerable to prediction errors related to spatial sampling bias and model complexity. Despite elevated rates of biodiversity imperilment in stream ecosystems, the application of Maxent models to stream networks has lagged, as has the availability of tools to address potential sources of error and calculate model evaluation metrics when modeling in nonraster environments (such as stream networks). Herein, we use Maxent and customized R code to estimate the potential distribution of paddlefish (Polyodon spathula) at a stream‐segment level within the Arkansas River basin, USA, while accounting for potential spatial sampling bias and model complexity. Filtering the presence data appeared to adequately remove an eastward, large‐river sampling bias that was evident within the unfiltered presence dataset. In particular, our novel riverscape filter provided a repeatable means of obtaining a relatively even coverage of presence data among watersheds and streams of varying sizes. The greatest differences in estimated distributions were observed among models constructed with default versus AICC‐selected parameterization. Although all models had similarly high performance and evaluation metrics, the AICC‐selected models were more inclusive of westward‐situated and smaller, headwater streams. Overall, our results solidified the importance of accounting for model complexity and spatial sampling bias in SDMs constructed within stream networks and provided a roadmap for future paddlefish restoration efforts in the study area. [ABSTRACT FROM AUTHOR]

A study was conducted to identify mononuclear cationic[M(v)=O](super 3+) (M=Tc,Re) complexes for radiopharmaceutical applications. The open-chain ligand, 1,4,8,11-tetraazaundecane-5,7-dione(dioxo-tetH(sub 6)) with two amine and two amide donors were investigated.

The factors dictating the structures and the solution chemistry of Re(V)=O(N(sub 2)S(sub 2)) complexes with ligands derived from cysteine (cys)(super 1-8) was investiaged. The study stated that ligand exchange of the isomeric mixture of TMECH(sub 6) with ReIO(sub 2)(PPh(sub 3))(sub 2) resulted in the formation of a mixture of ReO(TIME(H(sub 3)) isomers.