Melioidosis is caused by Burkholderia pseudomallei, a Gram-negative bacillus, primarily found in soils in Southeast Asia and northern Australia. A recent case of melioidosis in non-endemic Arizona was determined to be the result of locally acquired infection, as the patient had no travel history to endemic regions and no previous history of disease. Diagnosis of the case was confirmed through multiple microbiologic and molecular techniques. To enhance the epidemiological analysis, we conducted several molecular genotyping procedures, including multi-locus sequence typing, SNP-profiling, and whole genome sequence typing. Each technique has different molecular epidemiologic advantages, all of which provided evidence that the infecting strain was most similar to those found in Southeast Asia, possibly originating in, or around, Malaysia. Advancements in new typing technologies provide genotyping resolution not previously available to public health investigators, allowing for more accurate source identification.
This study draws the link between COVID-19 and air pollution (ground ozone O3) from February 29, 2020 to July 10, 2020 in the top 10 affected States of the US. Utilizing quantile-on-quantile (QQ) estimation technique, we examine in what manner the quantiles of COVID-19 affect the quantiles of air pollution and vice versa. The primary findings confirm overall dependence between COVID-19 and air pollution. Empirical results exhibit a strong negative effect of COVID-19 on air pollution in New York, Texas, Illinois, Massachusetts, and Pennsylvania; especially at medium to higher quantiles, while New Jersey, Illinois, Arizona, and Georgia show strong negative effect mainly at lower quantiles. Contrarily, COVID-19 positively affects air pollution in Pennsylvania at extreme lower quantiles. On the other side, air pollution predominantly caused to increase in the intensity of COVID-19 cases across all states except lower quantiles of Massachusetts, and extreme higher quantiles of Arizona and New Jersey, where this effect becomes less pronounced or negative. Concludingly, a rare positive fallout of COVID-19 is reducing environmental pressure, while higher environmental pollution causes to increase the vulnerability of COVID-19 cases. These findings imply that air pollution is at the heart of chronic diseases, therefore the state government should consider these asymmetric channels and introduce appropriate policy measures to reset and control atmospheric emissions.
Growth and development rates may result from genetic programming of intrinsic processes that yield correlated rates between life stages. These intrinsic rates are thought to affect adult mortality probability and longevity. However, if proximate extrinsic factors (e.g., temperature, food) influence development rates differently between stages and yield low covariance between stages, then development rates may not explain adult mortality probability. We examined these issues based on study of 90 songbird species on four continents to capture the diverse life-history strategies observed across geographic space. The length of the embryonic period explained little variation (ca. 13%) in nestling periods and growth rates among species. This low covariance suggests that the relative importance of intrinsic and extrinsic influences on growth and development rates differs between stages. Consequently, nestling period durations and nestling growth rates were not related to annual adult mortality probability among diverse songbird species within or among sites. The absence of a clear effect of faster growth on adult mortality when examined in an evolutionary framework across species may indicate that species that evolve faster growth also evolve physiological mechanisms for ameliorating costs on adult mortality. Instead, adult mortality rates of species in the wild may be determined more strongly by extrinsic environmental causes.
A new cavernicolous, arachnophilous thread-legged bug (Phasmatocoris labyrinthicus sp. nov.; Reduviidae: Emesini) is described from Kartchner Caverns, a limestone cavern in Kartchner Caverns State Park near Benson, Arizona, USA. Cavernicolous emesines are recorded from caves in many parts of the world and are distributed across several genera, but are generally uncommon. P. labyrinthicus shows no obvious troglomorphy but ecological evidence suggests it is, at minimum, a cave-limited troglophile. The species seems to be low-humidity intolerant, due to its occurrence in a cave within a desert region, effectively confines the population to the cave, and the species may thus actually be troglobitic by default. Arachnophily in emesines is more common, including in Phasmatocoris Breddin, but has been previously documented in only a single cavernicolous species, Bagauda cavernicola Paiva, reported from India, Malaysia and Sri Lanka. However, unlike P. labyrinthicus, B. cavernicola is apparently not morphologically adapted for its arachnophilous association. P. labyrinthicus is the only known troglophilic emesine that is also a morphologically adapted and behaviorally functional arachnophile. The only other known cavernicolous Phasmatocoris (P. xavieri Gil-Santana, Alves, Barrett and Costa) is recorded from a sandstone cave in Brazil. P. xavieri exhibits morphological features indicative of a potentially arachnophilous habit, but its ecology has not been studied. Adults of P. labyrinthicus share characteristics with the species Phasmatocoris praecellens Bergroth, P. minor McAtee and Malloch, P. xavieri, P. spectrum Breddin, and P. rapax McAtee and Malloch. Phasmatocoris is primarily a Neotropical genus and the discovery of P. labyrinthicus represents a significant range extension for the genus, being the first Nearctic species identified, with its geographically nearest relative an undescribed species from Mazatlan, Mexico, over 1,000 km to the south.
Life history theory attempts to explain why species differ in offspring number and quality, growth rate, and parental effort. I show that unappreciated interactions of these traits in response to age-related mortality risk challenge traditional perspectives and explain life history evolution in songbirds. Counter to a long-standing paradigm, tropical songbirds grow at similar overall rates to temperate species but grow wings relatively faster. These growth tactics are favored by predation risk, both in and after leaving the nest, and are facilitated by greater provisioning of individual offspring by parents. Increased provisioning of individual offspring depends on partitioning effort among fewer young because of constraints on effort from adult and nest mortality. These growth and provisioning responses to mortality risk finally explain the conundrum of small clutch sizes of tropical birds.
Intrinsic processes are assumed to underlie life history expression and trade-offs, but extrinsic inputs are theorised to shift trait expression and mask trade-offs within species. Here, we explore application of this theory across species. We do this based on parentally induced embryo temperature as an extrinsic input, and mass-specific embryo metabolism as an intrinsic process, underlying embryonic development rate. We found that embryonic metabolism followed intrinsic allometry rules among 49 songbird species from temperate and tropical sites. Extrinsic inputs via parentally induced temperatures explained the majority of variation in development rates and masked a relationship with metabolism; metabolism explained a minor proportion of the variation in development rates among species, and only after accounting for temperature effects. We discuss evidence that temperature further obscures the expected interspecific trade-off between development rate and offspring quality. These results demonstrate the importance of considering extrinsic inputs to trait expression and trade-offs across species.
Madagascar periwinkle, Catharanthus roseus (L.) G. Don, is a member of the Apocynaceae plant family that is native to Madagascar and produces dimeric terpenoid indole alkaloids that are used in the treatment of hypertension and cancer. Periwinkle as an indicator plant is highly susceptible to phytoplasmas and spiroplasma infection from different crops, and has been found to be naturally infected with spiroplasmas in Arizona, California, and the Mediterranean countries. In this study, surveys of suspected diseased periwinkles were conducted in various regions of Selangor State, Malaysia. Periwinkles showing rapid decline in the number and size of the flowers, premature abscission of buds and flowers, reduction in leaf size, chlorosis of the leaf tips and margins, general chlorosis, and stunting and dying plants were collected. These symptoms were widespread on periwinkle in this state. Diagnosis of the disease was based on symptomatology, grafting, serology (ELISA), PCR techniques, and cultivation. Tests for transmission by grafting were conducted using symptomatic periwinkle plants. Symptoms were induced on all eight graft-inoculated healthy periwinkles approximately 2 weeks after side grafting. Preliminary examination was performed by ELISA with Spiroplasma citri Saglio polyclonal antibody that was prepared against an Iranian S. citri isolate (H. Rahimian, unpublished data). Leaf extracts of all 24 symptomatic periwinkles gave positive ELISA reactions at OD405 readings ranging from 0.310 to 0.654 to the antibody against S. citri by the indirect ELISA method. Six healthy periwinkle leaves gave OD405 readings around 0.128. Total nucleic acids were extracted from 10 symptomatic and 5 asymptomatic plants (4). PCR using the ScR16F1/ScR16R1 primer pair designed to detect S. citri in carrot and P1/P7 and secA for1/rev3 primer pairs designed for identification of phytoplasmas were used to detect the causal agent (1-3). Amplification failed when the P1/P7 universal phytoplasma primer pair was used for diseased samples. However, the PCR assays resulted in products of 1,833 and 800 bp with ScR16F1/ScR16R1 and secA for1/rev3, respectively. Five of each ScR16F1/ScR16R1 and SecAfor1/SecArev3 products were cloned with the Topo TA cloning kit (Invitrogen, Carlsbad, CA), sequenced, and deposited as GenBank Accession Nos. HM015669 and FJ011099, respectively. Sequences for both genes indicated that S. citri was associated with the disease on periwinkle. ScR16F1/ScR16R1 products cloned from symptomatic periwinkles had 98% sequence identity with S. citri (GenBank Accession No. AM285316), while nucleotide sequences of SecAfor1/SecArev3 products had 88% sequence identity with S. citri GII3-3X (GenBank Accession No. AM285304). S. citri was cultivated from 10 S. citri-infected periwinkles using filtration and SP-4 media. Twenty culture tubes started to change culture medium color from red to yellow 1 month after cultivation. Helical and motile S. citri was observed in the dark-field microscope. To our knowledge, this is the first report on the presence and occurrence of S. citri in Southeast Asia and its association with lethal yellows on periwinkle in Malaysia. References: (1) J. Hodgetts et al. Int. J. Syst. Evol. Microbiol. 58:1826, 2008. (2) I.-M. Lee et al. Phytopathology 85:728, 1995. (3) I.-M. Lee et al. Plant Dis. 90:989, 2006. (4) Y.-P. Zhang et al. J. Virol. Methods. 71:45, 1998.