Pollination-induced flower senescence is expected in species of dry habitats with large long-lived water-demanding flowers as means for reducing floral maintenance costs. We investigated this ...hypothesis in
Alstroemeria umbellata
, an alpine species of the semiarid central Chilean Andes. Pollinator-excluded flowers were submitted to hand cross-pollination and manual pollen removal and monitored twice daily to assess the time spans of four floral stages and two expressions of flower longevity. Wilting and floral stage duration responses in open-pollinated flowers were studied. Ramet-level floral and leaf water content were quantified. Pollen removal had no effect on any floral trait analyzed. Hand cross-pollination reduced the functional flower lifespan from 7.5 to 6.7 days and the female stage from 3.4 to 1.6 days, but did not have a clear effect on the total flower lifespan (9.3 days). Counterintuitively, the length of the dehydration stage increased following pollination. No effect of pollination was detected in naturally pollinated flowers. Inflorescences contained > 3.5 g of water, > 3 times more than the ramet leaves, with > 50% of floral water housed in the turgid tepals. Although inflorescences contain much more water than the leaves, based on the open-pollination results, the amount of tepal water saved through pollination-associated floral senescence under natural circumstances is likely to be far less than the ~ 11% predicted by the manipulative experiment. Knowledge of tepal and leaf transpiration rates and the water content of underground plant parts is desirable to arrive at a more precise assessment of the impact of pollination-associated floral senescence on the water balance in
A. umbellata
.
The genus Leucheria Lag. (Asteraceae Bercht. and J. Presl, tribe Nassauvieae Cass.) comprises 45 species and three infraspecific taxa distributed in the Andean region from southern Chile and ...Argentina to Peru. Six species are annual herbs. The genus has had a long taxonomic history involving the transference of species described originally under many different genera. The main objectives of this paper were to determine the phylogenetic relationships of species of Leucheria, examine the hypothesis that the ancestor of Leucheria would have originated in a forested habitat and examine the validity of nine morphologically defined evolutionary lines recognized in earlier work on the genus. Additionally we investigated whether the annual species of Leucheria are derived. We extracted DNA from leaf material for 45 taxa (94%) of Leucheria. We used Bayesian inference and plastid and nuclear genes to construct a phylogenetic hypothesis. Results show that Leucheria is monophyletic and is comprised of two main clades. One clade comprises perennial acaulescent/subacaulescent species, all with a solitary capitulum. We recognized three lineages in the second clade comprised of caulescent species that exhibit multiple capitula. Optimization of life-form over the phylogeny showed that five of the six annual species studied are derived in our tree. We conclude that the appearance of the annual habit is associated with the colonization of arid conditions in the winter rainfall coastal desert of northern Chile. Our result shows that species of Leucheria from forested habitats are derived. Discrepancies with previously recognized morphologically defined evolutionary lines were detected.
The terrestrial fauna of Antarctica consists of a limited number of species, notably insects, small crustaceans and other micro-invertebrates. Over long periods of evolutionary isolation, these ...organisms have developed varying degrees of tolerance to multifaceted environmental stresses. Recent molecular biogeographical research highlights the enduring persistence of much of Antarctica’s current terrestrial fauna, with estimates spanning from hundreds of thousands to millions of years. Parochlus steinenii , commonly known as the Antarctic winged midge, stands out as one of the only two insect species native to Antarctica. Distributed across three biogeographic regions, southern South America and the Falkland/Malvinas Islands, sub-Antarctic South Georgia and the Maritime Antarctic South Shetland Islands, this midge raises questions about the temporal isolation of its populations and their divergence. Employing mitochondrial and nuclear genetic markers, we conducted phylogeographic and demographic analyses on 151 individuals of P. steinenii obtained across the three main biogeographic regions including the Magellanic sub-Antarctic Ecoregion (MSE) of southern South America, the sub-Antarctic Island of South Georgia (SG) and the South Shetland Islands (SSI) within the Maritime Antarctic (MA). Our data support the diversification of P. steinenii during the mid-Pleistocene around 1.46 Mya. This period included a branching event between a clade containing only specimens from the MSE and a clade containing individuals from a broader range of locations including the SSI and SG. Based on intraspecific phylogeographic and demographic inferences, we detected strong evolutionary divergence between the three main biogeographic regions. We also detected a signal of population growth during the deglaciation process in SSI and SG, contrary to the pattern seen in the MSE. The different demographic and phylogeographic histories between the sampled biogeographic regions could result from the MA and SG experiencing a strong genetic bottleneck due to a reduction in population size during the Last Glacial Maximum, while the MSE maintained a significant effective population size. The high level of divergence detected between individuals from the MSE and the remaining biogeographic regions supports the hypothesis of a speciation process taking place in P. steinenii .
Previous studies have shown that acupuncture and electroacupuncture (EA) are effective in the treatment of patients with low back pain. However, there is little evidence to support the use of one ...intervention over the other. The aim of this study is to compare the effect of acupuncture and electroacupuncture in the treatment of pain and disability in patients with chronic nonspecific low back pain.
The study design is a randomized controlled trial. Patients with nonspecific chronic low back pain of more than three months duration are recruited at Rehabilitation Center of Taboao da Serra - SP (Brazil). After examination, sixty-six patients will be randomized into one of two groups: acupuncture group (AG) (n = 33) and electroacupuncture group (EG) (n = 33). Interventions will last one hour, and will happen twice a week for 6 weeks. The primary clinical outcomes will be pain intensity as measured and functional disability.
quality of pain, quality of life. perception of the overall effect, depressive state, flexibility and kinesiophobia. All the outcomes will be assessed will be assessed at baseline, at treatment end, and three months after treatment end. Significance level will be determined at the 5 % level. Results of this trial will help clarify the value of acupuncture and electroacupuncture as a treatment for chronic low back pain and if they are different.
Results of this trial will help clarify the value of acupuncture needling and electroacupuncture stimulation of specific points on the body as a treatment for chronic low back pain.
Clinicaltrials.gov: NCT02039037 . Register October 30, 2013.
The genus Triptilion is endemic to central Chile, the Mendoza Province and western Patagonia in Argentina. It is currently composed of seven species: T. achilleae, T. benaventii, T. berteroi, T. ...capillatum, T. cordifolium, T. gibbosum, and T. spinosum. The main objectives of this paper were to determine the phylogenetic relationships of species of Triptilion. We also traced the evolution of annual and perennial life‐forms. Historically a close relationship has been described between genera Triptilion and Nassauvia. Phylogenetic analysis of the genus Triptilion and more closely related genera was undertaken using two nuclear (ITS, ETS) and two chloroplast (trnL‐F, rpl32‐trnL) markers. The topology of the Bayesian inference tree shows that the genus Triptilion is paraphyletic, because Nassauvia lagascae, the only representative of Nassauvia section Caloptilium grouped with T. achilleae, Clade I. The other species of Triptilion form two clades: Clade II composed of T. cordifolium and T. gibbosum and Clade III that includes T. benaventii, T. berteroi, T. capillatum, and T. spinosum. The genus Triptilion originated and diverged during the Miocene. The results of the life history reconstructions indicate that the common ancestor of Triptilion and Nassauvia was perennial. The annual habit appears to be derived in Triptilion. The life‐form of the common ancestor of Triptilion was ambiguous; it may have been annual or perennial.
To identify risk factors associated with nosocomial bloodstream infections caused by multiple clones of the staphylococcal cassette chromosome mec (SCCmec) type IV strain of methicillin-resistant ...Staphylococcus aureus (MRSA).
An unmatched case-control study (at a ratio of 1:2) performed during the period from October 2002 through September 2003.
A 2,000-bed tertiary care teaching hospital affiliated with the University of São Paulo in São Paulo, Brazil.
Case patients (n=30) were defined either as patients who had a bloodstream infection due to SCCmec type IV MRSA diagnosed at least 48 hours after hospital admission or as neonates with the infection who were born in the hospital. Control patients (n=60) were defined as patients with SCCmec type III MRSA infection diagnosed at least 48 hours after hospital admission. Genes encoding virulence factors were studied in the isolates recovered from case patients, and molecular typing of the SCCmec type IV MRSA isolates was also done by pulsed-field gel electrophoresis and multilocus sequence typing.
In multivariate analysis, the following 3 variables were significantly associated with having a nosocomial bloodstream infection caused by SCCmec type IV strains of MRSA: an age of less than 1 year, less frequent use of a central venous catheter (odds ratio OR, 0.07 95% confidence interval {CI}, 0.02-0.28; p= .025), and female sex. A second analysis was performed that excluded the case and control patients from the neonatal unit, and, in multivariate analysis, the following variables were significantly associated with having a nosocomial bloodstream infection caused by SCCmec type IV strains of MRSA: less frequent use of a central venous catheter (OR, 0.12 95% CI, 0.03-0.55; p= .007), lower Acute Physiology and Chronic Health Evaluation II score on admission (OR, 0.14 95% CI, 0.03-0.61; p= .009), less frequent surgery (OR, 0.21 95% CI, 0.06-0.83; p= .025), and female sex (OR, 5.70 95% CI, 1.32-24.66; p= .020). Of the 29 SCCmec type IV MRSA isolates recovered from case patients, none contained the Panton-Valentine leukocidin, gamma-hemolysin, enterotoxin B or C, or toxic shock syndrome toxin-1. All of the isolates contained genes for the LukE-LukD leukocidin and alpha-hemolysin. Genes for enterotoxin A were present in 1 isolate, and genes for beta-hemolysin were present in 3 isolates.
"Classical" risk factors do not apply to patients infected with the SCCmec type IV strain of MRSA, which is an important cause of nosocomial bacteremia. This strain infects a patient population that is less ill and has had less frequent invasive procedures than a patient population infected with the multidrug-resistant strain of SCCmec type III MRSA. We found that virulence factors were rare and that Panton-Valentine leukocidin was absent. There were multiple clones of the SCCmec type IV strain in our hospital. Children under 1 year of age were at a higher risk. There was a predominant clone (sequence type 5) in this patient population.
Introducción y objetivos: Las prácticas de manejo de especies no-nativas e invasoras es tema prioritario en áreas protegidas, en especial en estadios tempranos de invasión, porque facilita la ...recuperación de sistemas nativos. Aquí presentamos una metodología para el control de una planta trepadora invasora, Hedera helix (Araliaceae).
M&M: Se realizó remoción manual y la disposición de los residuos se compostó en bolsas en el lugar. Luego se monitoreó la regeneración natural del bosque nativo. La propuesta incluye la convocatoria de voluntarios, enmarcados en un proyecto de investigación y extensión de la Universidad Nacional Comahue Bariloche con la colaboración de la Administración de Parques Nacionales.
Resultados: Desde 2019 participaron 47 voluntarios, se extrajeron 870 kg (peso húmedo) de material de cinco de los seis sitios identificados. Dos de los cinco sitios intervenidos se encuentran en la etapa de monitoreo de especies nativas.
Conclusión: La participación de voluntarios resultó efectiva en términos de las acciones de control manual, al estar los sitios controlados. De esta manera, se está logrando con éxito un mínimo impacto negativo sobre el entorno, al menos en las especies de plantas, evidenciado por una rápida recolonización pasiva de especies nativas y la eliminación la especie invasora en los sitios intervenidos. En particular, este modo de trabajo permite crear conciencia del problema de las invasiones biológicas en la comunidad y en futuros profesionales. También fortalece las relaciones entre instituciones vinculando la academia con la gestión en conservación, un aspecto a veces difícil de lograr.
Precipitation using sulfide is an alternative method for the recovery and reuse of metal ions present in industrial effluents. This work explored the selective precipitation of Cu(II), Zn(II) and ...Ni(II) using H2S(g) generated by the hydrolysis of thioacetamide. The studies were conducted on a laboratory scale in two stages. In the first stage, precipitation studies were performed for each individual ion (100 mg L–1) at varying pH levels (0.5–6.0) and contact times (30–150 min). In the second stage, tests were performed in multielement solutions. Individual precipitation studies showed that Cu(II) precipitates in the first 30 min, and at all tested pH values, 99.9% of the copper ions were removed. The precipitation of Zn(II) required 60 min of contact time with the gas and a pH above 4.0 to reach greater than 95% removal of the ions. Ni(II) began to precipitate at pH 6.0 after 120 min and reached greater than 90% removal. In the second stage, the fractional precipitation studies of Cu2+–Zn2+ and Cu2+–Ni2+ systems, it was possible to separate and precipitate both metal ions above 90%. For the Zn2+–Ni2+ system, rigid control of pH was required to separate the metal sulfides because of their very close pKps values, but a removal of 90% was achieved for both ions. The results of the fractional separation involving three metal ions, Cu(II), Zn(II) and Ni(II), were satisfactory and did not require the use of complexing agents.
HIV incidence estimation is critical for monitoring the HIV epidemic dynamics and the effectiveness of public health prevention interventions. We aimed to identify sexual and gender minorities (SGM) ...with recent HIV infections, factors associated with recent HIV infection, and to estimate annualised HIV incidence rates.
Cross-sectional multicentre study in HIV testing services in Brazil and Peru (15 cities). Inclusion criteria: 18+ years, SGM assigned male at birth, not using pre-/post-exposure prophylaxis. We identified recent HIV infection using the Maxim HIV-1 LAg-Avidity EIA assay as part of a recent infection testing algorithm (RITA). Annualized HIV incidence was calculated using the UNAIDS/WHO incidence estimator tool. Multivariable logistic regression models were used to estimate factors associated with recent HIV infection. Trial registration: NCT05674682.
From 31-Jan-2021 to 29-May-2022, 6899 individuals participated Brazil: 4586 (66.5%); Peru: 2313 (33.5%); 5946 (86.2%) cisgender men, 751 (10.9%) transgender women and 202 (2.9%) non-binary/gender diverse. Median age was 27 (IQR: 23-34) years. HIV prevalence was 11.4% (N = 784/6899); 137 (2.0%) SGM were identified with recent HIV infection. The overall annualized HIV incidence rate was 3.88% (95% CI: 2.86-4.87); Brazil: 2.62% (95% CI: 1.78-3.43); Peru: 6.69% (95% CI: 4.62-8.69). Participants aged 18-24 years had higher odds of recent HIV infection compared to those aged 30+ years in both countries.
Our results highlight the significant burden of HIV epidemic among SGM in large urban centres of Brazil and Peru. Public health policies and interventions to increase access to effective HIV prevention methods such as PrEP are urgently needed in Latin America.
Unitaid, WHO (Switzerland), Ministry of Health from Brazil and Peru.
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