Annotated Checklist of Mammals of the Yucatán Peninsula, México. II. Rodentia

The Yucatán Peninsula, as encompassed in this series of papers, includes the Mexican states of Campeche and Yucatán, and the Federal Territory of Quintana Roo. This region is a low-lying plain that rises gently in elevation from north to south. It is surrounded on three sides by water and bounded on the south by British Honduras (i.e. Belize), Guatemala, and the Mexican state of Tabasco. The vegetation of the peninsula increases in height from north to south and from the coast inland. Generally, forest to the north is xerophilic, but that of the southern part of the peninsula is tall, quasi rainforest. Although the mammalian fauna of the Yucatán Peninsula is unique in many ways, there has been no comprehensive account of mammals of the region since Gaumer\u27s (1917) Monografía de los mamíferos de Yucatán. In an earlier paper of this series (Jones, et al., 1973), the chiropteran fauna of the peninsular region was treated. The present report deals exclusively with rodents, 20 native species of which (and two that have been introduced) presently are known from the Yucatán Peninsula. These 22 species represent 16 genera of seven families as follows: Sciuridae, two; Geomyidae, one; Heteromyidae, two; Cricetidae, 12; Muridae, two (introduced); Dasyproctidae, two; and Erethizontidae, one. One genus (Otonyctomys) is endemic to the peninsula, as are four species (Sciurus yucatanicus, Heteromys gaumeri, Peromyscus yucatanicus, and Reithrodontomys spectabilisi and a number of subspecies. This report is based principally upon material housed in the Museum of Natural History at the University of Kansas. In the summer of 1962, two field parties from Kansas visited the region, one consisting of W.E. Duellman and six students enrolled in a field course in vertebrate zoology, and the other including the senior author and four students working on a survey of terrestrial vertebrates and their ectoparasites under the aegis of a contract (DA-49-193MD- 2215) from the U.S. Army Research and Development Command. Also, Percy L. Clifton, field representative of the Museum of Natural History, collected mammals on the peninsula from mid-December 1962 until June 1963. Collections from which specimens were examined are: Museum of Natural History at The University of Kansas, the American Museum of Natural History, the British Museum (Natural History), the University of Michigan Museum of Zoology, the Museum, Texas Tech University, and the National Museum of Natural History. Most localities mentioned in text are plotted in a map. Ectoparasites obtained from our material from the Yucatán Peninsula have been reported by Emerson (1971), Genoways (1973), Lawlor (1965, 1969), Loomis (1969), and Price and Emerson (1971)

Use of soil moisture information in yield models

There are no author-identified significant results in this report

Variation in the SLC23A1 gene does not influence cardiometabolic outcomes to the extent expected given its association with L-ascorbic acid

Background: Observational studies showed that circulating l-ascorbic acid (vitamin C) is inversely associated with cardiometabolic traits. However, these studies were susceptible to confounding and reverse causation. Objectives:We assessed the relation between l-ascorbic acid and 10 cardiometabolic traits by using a single nucleotide polymorphism in the solute carrier family 23 member 1 (SLC23A1) gene (rs33972313) associated with circulating l-ascorbic acid concentrations. The observed association between rs33972313 and cardiometabolic outcomes was compared with that expected given the rs33972313-l-ascorbic acid and l-ascorbic acid–outcome associations. Design: A meta-analysis was performed in the following 5 independent studies: the British Women's Heart and Health Study (n = 1833), the MIDSPAN study (n = 1138), the Ten Towns study (n = 1324), the British Regional Heart Study (n = 2521), and the European Prospective Investigation into Cancer (n = 3737). Results: With the use of a meta-analysis of observational estimates, inverse associations were shown between l-ascorbic acid and systolic blood pressure, triglycerides, and the waist-hip ratio [the strongest of which was the waist-hip ratio (−0.13-SD change; 95% CI: −0.20-, −0.07-SD change; P = 0.0001) per SD increase in l-ascorbic acid], and a positive association was shown with high-density lipoprotein (HDL) cholesterol. The variation at rs33972313 was associated with a 0.18-SD (95% CI: 0.10-, 0.25-SD; P = 3.34 × 10−6) increase in l-ascorbic acid per effect allele. There was no evidence of a relation between the variation at rs33972313 and any cardiometabolic outcome. Although observed estimates were not statistically different from expected associations between rs33972313 and cardiometabolic outcomes, estimates for low-density lipoprotein cholesterol, HDL cholesterol, triglycerides, glucose, and body mass index were in the opposite direction to those expected. Conclusions: The nature of the genetic association exploited in this study led to limited statistical application, but despite this, when all cardiometabolic traits were assessed, there was no evidence of any trend supporting a protective role of l-ascorbic acid. In the context of existing work, these results add to the suggestion that observational relations between l-ascorbic acid and cardiometabolic health may be attributable to confounding and reverse causation

Nonstomatal limitations are responsible for drought-induced photosynthetic inhibition in four C4 grasses

Here, the contribution of stomatal and nonstomatal factors to photosynthetic inhibition under water stress in four tropical C(4) grasses was investigated (Panicum coloratum, Bothriochloa bladhii, Cenchrus ciliaris and Astrebla lappacea ). Plants were grown in well watered soil, and then the effects of soil drying were measured on leaf gas exchange, chlorophyll a fluorescence and water relations. During the drying cycle, leaf water potential (Psi(leaf)) and relative water content (RWC) decreased from c. -0.4 to -2.8 MPa and 100-40%, respectively. The CO(2) assimilation rates (A) and quantum yield of PSII (Phi(PSII)) of all four grasses decreased rapidly with declining RWC. High CO(2) concentration (2500 mul l(-1)) had no effect on A or Phi(PSII) at any stage of the drying cycle. Electron transport capacity and dark respiration rates were unaltered by drought. The CO(2) compensation concentrations of P. coloratum and C. ciliaris rose sharply when leaf RWC fell below 70%. In P. coloratum, 5% CO(2) did not prevent the decline of O(2) evolution rates under water stress. We conclude that inhibition of photosynthesis in the four C(4) grasses under water stress is dependent mainly on biochemical limitations

Socioeconomic position and hysterectomy: a cross-cohort comparison of women in Australia and Great Britain

Objectives: To examine the associations between indicators of socioeconomic position (SEP) and hysterectomy in two Australian and two British cohorts

Coming Full Circle: Reflections and Inspirations from a Cystic Fibrosis Patient Scientist Panel

Care for many progressive chronic diseases continues to improve, allowing patients to survive and thrive for longer periods of time1. People living with such conditions may now find themselves able to achieve long-term goals in education and career development2. Many people now occupy the dual roles of scientist and patient3. This commentary article synthesizes experiences of scientists and advocates with the progressive genetic disease cystic fibrosis (CF) who collaborated on a career development session for the Cystic Fibrosis Foundation’s inaugural ResearchCon event in 2019. It explores how such collaborations affirm and transform individual perspectives on patient science and its importance in broader scientific research agenda setting. We first share our own individual insights about the experience and impact of the ResearchCon panel session before progressing to discussion and future directions centering the shared insights from one another’s reflections

Muscle-directed gene therapy corrects Pompe disease and uncovers species-specific GAA immunogenicity

Pompe disease is a severe disorder caused by loss of acid α-glucosidase (GAA), leading to glycogen accumulation in tissues and neuromuscular and cardiac dysfunction. Enzyme replacement therapy is the only available treatment. AT845 is an adeno-associated viral vector designed to express human GAA specifically in skeletal muscle and heart. Systemic administration of AT845 in Gaa−/− mice led to a dose-dependent increase in GAA activity, glycogen clearance in muscles and heart, and functional improvement. AT845 was tolerated in cynomolgus macaques at low doses, while high doses caused anti-GAA immune response, inflammation, and cardiac abnormalities resulting in unscheduled euthanasia of two animals. Conversely, a vector expressing the macaque GAA caused no detectable pathology, indicating that the toxicity observed with AT845 was an anti-GAA xenogeneic immune response. Western blot analysis showed abnormal processing of human GAA in cynomolgus muscle, adding to the species-specific effects of enzyme expression. Overall, these studies show that AAV-mediated GAA delivery to muscle is efficacious in Gaa−/− mice and highlight limitations in predicting the toxicity of AAV vectors encoding human proteins in non-human species

Clarification of the Bootstrap Percolation Paradox

We study the onset of the bootstrap percolation transition as a model of generalized dynamical arrest. We develop a new importance-sampling procedure in simulation, based on rare events around "holes", that enables us to access bootstrap lengths beyond those previously studied. By framing a new theory in terms of paths or processes that lead to emptying of the lattice we are able to develop systematic corrections to the existing theory, and compare them to simulations. Thereby, for the first time in the literature, it is possible to obtain credible comparisons between theory and simulation in the accessible density range.Comment: 4 pages with 3 figure