272 research outputs found
How old is the Tasmanian cultural landscape? a test of landscape openness using quantitative land-cover reconstructions
Aim: To test competing hypotheses about the timing and extent of Holocene landscape opening using pollen-based quantitative land-cover estimates. Location: Dove Lake, Tasmanian Wilderness World Heritage Area, Australia. Methods: Fossil pollen data were incorporated into pollen dispersal models and corrected for differences in pollen productivity among key plant taxa. Mechanistic models (REVEALS-Regional Estimates of VEgetation Abundance from Large Sites) employing different models for pollen dispersal (Gaussian plume and Lagrangian stochastic models) were evaluated and applied in the Southern Hemisphere for the first time. Results: Validation of the REVEALS model with vegetation cover data suggests an overall better performance of the Lagrangian stochastic model. Regional land-cover estimates for forest and non-forest plant taxa show persistent landscape openness throughout the Holocene (average landscape openness similar to 50%). Gymnoschoenus sphaerocephalus, an indicator of moorland vegetation, shows higher values during the early Holocene (11.7-9 ka) and declines slightly through the mid-Holocene (9-4.5 ka) during a phase of partial landscape afforestation. Rain forest cover reduced (from similar to 40% to similar to 20%) during the period between 4.2-3.5 ka. Main conclusions: Pollen percentages severely under-represent landscape openness in western Tasmania and this bias has fostered an over-estimation of Holocene forest cover from pollen data. Treeless vegetation dominated Holocene landscapes of the Dove Lake area, allowing us to reject models of landscape evolution that invoke late-Holocene replacement of a rain forest-dominated landscape by moorland. Instead, we confirm a model of Late Pleistocene inheritance of open vegetation. Rapid forest decline occurred after c.4 ka, likely in response to regional moisture decline.Australian Research Council; AINSE AWARD [ALNGRA16024]; AINSE PGRA scholarship [12039]info:eu-repo/semantics/publishedVersio
Morphometric comparisons between extant and extinct Italian populations of the adder, Vipera berus (Linnaeus, 1758)
Simultaneous determination of natural and synthetic steroid estrogens and their conjugates in aqueous matrices by liquid chromatography / mass spectrometry
An analytical method for the simultaneous determination of nine free and conjugated steroid estrogens was developed with application to environmental aqueous matrices. Solid phase extraction (SPE) was employed for isolation and concentration, with detection by liquid chromatography/mass spectrometry (LC/MS) using electrospray ionisation (ESI) in the negative mode. Method recoveries for various aqueous matrices (wastewater, lake and drinking water) were determined, recoveries proving to be sample dependent. When spiked at 50 ng/l concentrations in sewage influent, recoveries ranged from 62-89 % with relative standard deviations (RSD) < 8.1 %. In comparison, drinking water spiked at the same concentrations had recoveries between 82-100 % with an RSD < 5%. Ion suppression is a known phenomenon when using ESI; hence its impact on method recovery was elucidated for raw sewage. Both ion suppression from matrix interferences and the extraction procedure has bearing on the overall method recovery. Analysis of municipal raw sewage identified several of the analytes of interest at ng/l concentrations, estriol (E3) being the most abundant. Only one conjugate, estrone 3-sulphate (E1-3S) was observe
Fate of conjugated natural and synthetic steroid estrogens in crude sewage and activated sludge batch studies
This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Environmental Science & Technology, copyright © American Chemical Society after peer review. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/es801952h.Steroids are excreted from the human body in the conjugated form but are present in sewage influent and effluent as the free steroid, the major source of estrogenic activity observed in water courses. The fate of sulfate and glucuronide conjugated steroid estrogens was investigated in batch studies using activated sludge grown on synthetic sewage in a laboratory-scale Husmann simulation and crude sewage from the field. A clear distinction between the fate of sulfate and glucuronide conjugates was observed in both matrices, with sulfated conjugates proving more recalcitrant and glucuronide deconjugation preferential in crude sewage. For each conjugate, the free steroid was observed in the biotic samples. The degree of free steroid formation was dependent on the conjugate moiety, favoring the glucuronide. Subsequent degradation of the free steroid (and sorption to the activated sludge solid phase) was evaluated. Deconjugation followed the first order reaction rate with rate constants for 17α-ethinylestradiol 3-glucuronide, estriol 16α-glucuronide, and estrone 3-glucuronide determined as 0.32, 0.24, and 0.35 h respectively. The activated sludge solid retention time over the range of 3−9 days had 74 to 94% of sulfate conjugates remaining after 8 h. In contrast, a correlation between increasing temperature and decreasing 17α-ethinylestradiol 3-glucuronide concentrations in the activated sludge observed no conjugate present in the AS following 8 h at 22 °C Based on these batch studies and literature excretion profiles, a hypothesis is presented on which steroids and what form (glucuronide, sulfate, or free) will likely enter the sewage treatment plant.EPSR
DIREÇÃO E PLANEJAMENTO DE INTELIGÊNCIA POLICIAL NO ENFRENTAMENTO ÀS ORGANIZAÇÕES CRIMINOSAS: Um estudo de caso sobre o Rio Grande do Norte
This article aims to investigate how the orientation phase of the intelligence cycle is conducted by the Military Police Area Battalions of the State of Rio Grande do Norte. Interviews were conducted with battalion commanders and heads of intelligence agencies in order to have an overview of how the direction and planning of intelligence aimed at confronting prison factions is carried out. The Public Security Intelligence activity is endowed with its own doctrine in which is indicated that the knowledge production process must follow a cycle composed of three phases. The first of these phases is the orientation, in which the directives and planning of the activity are defined. It was concluded that the guidance phase is carried out essentially by verbal demands without ties to government policies, as well as that intelligence plans are not used to delimit the process of producing knowledge about criminal organizations based on prisons operating in the areas of interviewed commanders and chiefs.El objetivo de este estudio es investigar cómo es conducida la fase de orientación del ciclo de inteligencia por los Batallones de Área de la Policía Militar en el estado de Rio Grande do Norte. Se realizaron entrevistas con comandantes de batallones y jefes de agencias de inteligencia para obtener una visión general de cómo se lleva a cabo la dirección y planificación de la inteligencia con vistas a enfrentar a las facciones carcelarias. La Inteligencia de Seguridad Pública (ISP) tiene su propia doctrina, que establece que el proceso de producción de conocimiento debe seguir un ciclo compuesto por tres fases. La primera de estas fases es la de orientación, en la que se definen las directrices y la planificación de la actividad. Se puede concluir que la fase de orientación se basa esencialmente en demandas verbales específicas sin vínculos con políticas gubernamentales o institucionales, y que los planes de inteligencia no se utilizan para delimitar el proceso de producción de conocimiento sobre las organizaciones criminales carcelarias que operan en las áreas de los comandantes y jefes entrevistados.Este trabalho tem o objetivo de investigar como a fase de orientação do ciclo de inteligência é conduzida pelos Batalhões de Área da Polícia Militar do Estado do Rio Grande do Norte. Foram feitas entrevistas com comandantes de Batalhão e chefes das agências de inteligência, para se ter um panorama de como é feita a direção e o planejamento de inteligência voltados ao enfrentamento das facções prisionais. A atividade de Inteligência de Segurança Pública (ISP) é dotada de doutrina própria, na qual se indica que o processo de produção de conhecimento deve seguir um ciclo composto de três fases. A primeira dessas fases é a orientação, na qual se definem as diretrizes e o planejamento da atividade. Conclui-se que a fase de orientação é pautada, essencialmente, por demandas verbais pontuais sem vínculos com políticas de governo ou institucionais, bem como que não são utilizados planos de inteligência para delimitar o processo de produção de conhecimento sobre as organizações criminosas de base prisional atuantes nas áreas dos comandantes e chefes entrevistados
Learning curve for laparoscopic cholecystectomy has not been defined: A systematic review
Background: Laparoscopic cholecystectomy is one of the most performed surgeries worldwide but its learning curve is still unclear. Methods: A systematic review was conducted according to the 2009 Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Two independent reviewers searched the literature in a systematic manner through online databases, including Medline, Scopus, Embase, and Google Scholar. Human studies investigating the learning curve of laparoscopic cholecystectomy were included. The Newcastle–Ottawa scale for cohort studies and the GRADE scale were used for the quality assessment of the selected articles. Results: Nine cohort studies published between 1991 and 2020 were included. All studies showed a great heterogeneity among the considered variables. Seven articles (77.7%) assessed intraoperative variables only, without considering patient's characteristics, operator's experience, and grade of gallbladder inflammation. Only five articles (55%) provided a precise cut-off value to see proficiency in the learning curve, ranging from 13 to 200 laparoscopic cholecystectomies. Conclusions: The lack of clear guidelines when evaluating the learning curve in surgery, probably contributed to the divergent data and heterogeneous results among the studies. The development of guidelines for the investigation and reporting of a surgical learning curve would be helpful to obtain more objective and reliable data especially for common operation such as laparoscopic cholecystectomy
Exploring the use of pegylated liposomal doxorubicin (Caelyx®) as pressurized intraperitoneal aerosol chemotherapy
Background: Peritoneal carcinomatosis is a common metastatic pattern in ovarian, gastric, colorectal, and appendiceal cancer; systemic chemotherapy is the current standard of care for peritoneal metastatic disease; however, in a subset of patients its beneficial effect remains questionable. More effective perioperative chemotherapy is needed. Materials and methods: Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a new treatment that applies chemotherapeutic drugs into the peritoneal cavity as an aerosol under pressure. It's a safe and feasible approach that improves local bioavailability of chemotherapeutic drugs as compared with conventional intraperitoneal chemotherapy. Till now the drugs used in PIPAC for the treatment of the peritoneal carcinomatosis (PC) are cisplatin, doxorubicin, and oxaliplatin; as of yet, there are no in vivo data comparing different drug formulations and dosage schedules of PIPAC. Pegylated liposomal doxorubicin 1.5 mg/sm was aerosolized in PIPAC procedures. Results: Pharmacokinetics analysis of 10 procedures performed with conventional doxorubicin solution at the dose of 1.5 mg/m2 were compared to 15 procedures with the same dose of pegylated liposomal doxorubicin (PLD). Significant differences between experimental groups were detected by one-way ANOVA followed by Bonferroni correction; a p value < 0.05 was considered statistically significant. A statistically different doxorubicin tissue concentration was observed for the doxorubicin solution compared to pegylated liposomal doxorubicin in the right parietal peritoneum and right diaphragm. In the Caelyx\uae series a mean tissue concentration of 1.27 \ub1 1.33 mg/g was reported, while in the second one we registered a mean concentration of 3.1 \ub1 3.7 mg/g. Conclusions: The delivery of nano-particles in PIPAC was feasible, but pegylated liposomal concentrations are lower than standard doxorubicin formulation. Probably mechanical and physical properties of pressurized aerosol chemotherapy might alter their stability and cause structural disintegration
Standard (8 weeks) vs long (12 weeks) timing to minimally-invasive surgery after NeoAdjuvant Chemoradiotherapy for rectal cancer: A multicenter randomized controlled parallel group trial (TiMiSNAR)
Background: The optimal timing of surgery in relation to chemoradiation is still controversial. Retrospective analysis has demonstrated in the recent decades that the regression of adenocarcinoma can be slow and not complete until after several months. More recently, increasing pathologic Complete Response rates have been demonstrated to be correlated with longer time interval. The purpose of the trial is to demonstrate if delayed timing of surgery after neoadjuvant chemoradiotherapy actually affects pathologic Complete Response and reflects on disease-free survival and overall survival rather than standard timing. Methods: The trial is a multicenter, prospective, randomized controlled, unblinded, parallel-group trial comparing standard and delayed surgery after neoadjuvant chemoradiotherapy for the curative treatment of rectal cancer. Three-hundred and forty patients will be randomized on an equal basis to either robotic-assisted/standard laparoscopic rectal cancer surgery after 8 weeks or robotic-assisted/standard laparoscopic rectal cancer surgery after 12 weeks. Discussion: To date, it is well-know that pathologic Complete Response is associated with excellent prognosis and an overall survival of 90%. In the Lyon trial the rate of pCR or near pathologic Complete Response increased from 10.3 to 26% and in retrospective studies the increase rate was about 23-30%. These results may be explained on the relationship between radiation therapy and tumor regression: DNA damage occurs during irradiation, but cellular lysis occurs within the next weeks. Study results, whether confirmed that performing surgery after 12 weeks from neoadjuvant treatment is advantageous from a technical and oncological point of view, may change the current pathway of the treatment in those patient suffering from rectal cancer. Trial registration: ClinicalTrials.gov NCT3465982
Standard (8 weeks) vs long (12 weeks) timing to minimally-invasive surgery after NeoAdjuvant Chemoradiotherapy for rectal cancer: a multicenter randomized controlled parallel group trial (TiMiSNAR)
BACKGROUND:
The optimal timing of surgery in relation to chemoradiation is still controversial. Retrospective analysis has demonstrated in the recent decades that the regression of adenocarcinoma can be slow and not complete until after several months. More recently, increasing pathologic Complete Response rates have been demonstrated to be correlated with longer time interval. The purpose of the trial is to demonstrate if delayed timing of surgery after neoadjuvant chemoradiotherapy actually affects pathologic Complete Response and reflects on disease-free survival and overall survival rather than standard timing.
METHODS:
The trial is a multicenter, prospective, randomized controlled, unblinded, parallel-group trial comparing standard and delayed surgery after neoadjuvant chemoradiotherapy for the curative treatment of rectal cancer. Three-hundred and forty patients will be randomized on an equal basis to either robotic-assisted/standard laparoscopic rectal cancer surgery after 8\u2009weeks or robotic-assisted/standard laparoscopic rectal cancer surgery after 12\u2009weeks.
DISCUSSION:
To date, it is well-know that pathologic Complete Response is associated with excellent prognosis and an overall survival of 90%. In the Lyon trial the rate of pCR or near pathologic Complete Response increased from 10.3 to 26% and in retrospective studies the increase rate was about 23-30%. These results may be explained on the relationship between radiation therapy and tumor regression: DNA damage occurs during irradiation, but cellular lysis occurs within the next weeks. Study results, whether confirmed that performing surgery after 12\u2009weeks from neoadjuvant treatment is advantageous from a technical and oncological point of view, may change the current pathway of the treatment in those patient suffering from rectal cancer
The indirect response of an aquatic ecosystem to long-term climate-driven terrestrial vegetation in a subalpine temperate lake
Aim: To assess whether climate directly influences aquatic ecosystem dynamics in
the temperate landscape of Tasmania or whether the effects of long-term climatic
change are mediated through the terrestrial environment (indirect climate influence).
Location: Paddy’s Lake is located at 1065 m a.s.l. in temperate north-west Tasmania,
a continental island south-east of mainland Australia (41°15–43°250 S; 145°00–
148°150 E).
Methods: We developed a new 13,400 year (13.4 kyr) palaeoecological dataset of
lake sediment subfossil cladocerans (aquatic grazers), bulk organic sediment carbon
(C%) and nitrogen (N%) and d13C and d15N stable isotopes. Comparison of this new
data was made with a recently published pollen, geochemistry and charcoal records
from Paddy’s Lake.
Results: Low cladoceran diversity at Paddy’s Lake is consistent with other temperate
Southern Hemisphere lakes. The bulk sediment d15N values demonstrate a significant
lagged negative response to pollen accumulation rate (pollen AR).
Compositional shifts of dominant cladoceran taxa (Bosmina meridionalis and Alona
guttata) occur following changes in both pollen AR and pollen (vegetation) composition
throughout the 13.4 kyr record at Paddy’s Lake. The d15N values demonstrate
a significant positive lagged relationship to the oligotrophic:eutrophic cladoceran
ratio.
Main conclusions: Long-term changes in cladoceran composition lag changes in
both pollen AR and terrestrial vegetation composition. We interpret pollen AR as
reflecting climate-driven changes in terrestrial vegetation productivity and conclude
that climate-driven shifts in vegetation are the principal driver of the cladoceran
community during the last ca. 13.4 kyr. The significant negative lagged relationship
between pollen AR and d15N reflects the primary control of vegetation productivity
over within-lake nutrient status. Thus, we conclude that the effects of long-term climate
change on aquatic ecosystem dynamics at our site are indirect and mediated
by the terrestrial environment. Vegetation productivity controls organic soil development
and has a direct influence over lake trophic status via changes in the delivery
of terrestrial organic matter into the lake
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