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91.
92.
AimTo analyse the efficacy and toxicity of postprostatectomy SRT in patients with a BCR evaluated with mpMRI.BackgroundMultiparametric magnetic resonance imaging (mpMRI) has the ability to detect the site of pelvic recurrence in patients with biochemical recurrence (BCR) after radical prostatectomy (RP). However, we do not know the oncological outcomes of mpMRI-guided savage radiotherapy (SRT).ResultsLocal, lymph node, and pelvic bone recurrence was observed in 13, 4 and 2 patients, respectively. PSA levels were significantly lower in patients with negative mpMRI (0.4 ng/mL [0.4]) vs. positive mpMRI (2.2 ng/mL [4.1], p = 0.003). Median planning target volume doses in patients with visible vs. non-visible recurrences were 76 Gy vs. 70 Gy. Overall, mean follow-up was 41 months (6–81). Biochemical relapse-free survival (bRFS) at 3 years was 82.3% and 82.5%, respectively, for the negative and positive mpMRI groups (p = 0.800). Three-year rates of late grade ≥2 urinary and rectal toxicity were 14.8% and 1.9%, respectively; all but one patient recovered without sequelae.ConclusionSRT to the macroscopic recurrence identified by mpMRI is a feasible and well-tolerated option. In this study, there were no differences in bRFS between MRI-positive and MRI-negative patients, indicating effective targeting of MRI-positive lesions.  相似文献   
93.
94.
Toxic aromatic pollutants, concentrated in industrial wastes and contaminated sites, can potentially be eliminated by low cost bioremediation systems. Most commonly, the goal of these treatment systems is directed at providing optimum environmental conditions for the mineralization of the pollutants by naturally occurring microflora. Electrophilic aromatic pollutants with multiple chloro, nitro and azo groups have proven to be persistent to biodegradation by aerobic bacteria. These compounds are readily reduced by anaerobic consortia to lower chlorinated aromatics or aromatic amines but are not mineralized further. The reduction increases the susceptibility of the aromatic molecule for oxygenolytic attack. Sequencing anaerobic and aerobic biotreatment steps provide enhanced mineralization of many electrophilic aromatic pollutants. The combined activity of anaerobic and aerobic bacteria can also be obtained in a single treatment step if the bacteria are immobilized in particulate matrices (e.g. biofilm, soil aggregate, etc.). Due to the rapid uptake of oxygen by aerobes and facultative bacteria compared to the slow diffusion of oxygen, oxygen penetration into active biofilms seldom exceeds several hundred micrometers. The anaerobic microniches established inside the biofilms can be applied to the reduction of electron withdrawing functional groups in order to prepare recalcitrant aromatic compounds for further mineralization in the aerobic outer layer of the biofilm.Aside from mineralization, polyhydroxylated and chlorinated phenols as well as nitroaromatics and aromatic amines are susceptible to polymerization in aerobic environments. Consequently, an alternative approach for bioremediation systems can be directed towards incorporating these aromatic pollutants into detoxified humic-like substances. The activation of aromatic pollutants for polymerization can potentially be encouraged by an anaerobic pretreatment step prior to oxidation. Anaerobic bacteria can modify aromatic pollutants by demethylating methoxy groups and reducing nitro groups. The resulting phenols and aromatic amines are readily polymerized in a subsequent aerobic step.  相似文献   
95.
In 2006–2007, an unusually high number of harbor porpoises (Phocoena phocoena) stranded along the Washington and Oregon coastlines. Spatiotemporal analyses were used to examine their ability to detect clusters of porpoise strandings during an unusual mortality event (UME) in the Pacific Northwest using stranding location data. Strandings were evaluated as two separate populations, outer coast and inland waters. The presence of global clustering was evaluated using the Knox spatiotemporal test, and the presence of local clusters was investigated using a spatiotemporal scan statistic (space–time permutation). There was evidence of global clustering, but no local clustering, supporting the hypothesis that strandings were due to more varied etiologies instead of localized causes. Further analyses at subregional levels, and concurrently assessing environmental factors, might reveal additional geographic distribution patterns. This article describes the spatial analytical tools applied in this study and how they can help elucidate the spatiotemporal epidemiology of other UMEs and assist in determining their causes. More than one spatial analytical technique should be used if the study objective is to detect and describe clustering in time and space and to generate hypotheses regarding causation of marine mammal disease and stranding events.  相似文献   
96.
  1. A central theme for conservation is understanding how animals differentially use, and are affected by change in, the landscapes they inhabit. However, it has been challenging to develop conservation schemes for habitat‐specific behaviors.
  2. Here we use behavioral change point analysis to identify behavioral states of golden eagles (Aquila chrysaetos) in the Sonoran and Mojave Deserts of the southwestern United States, and we identify, for each behavioral state, conservation‐relevant habitat associations.
  3. We modeled behavior using 186,859 GPS points from 48 eagles and identified 2,851 distinct segments comprising four behavioral states. Altitude above ground level (AGL) best differentiated behavioral states, with two clusters of short‐distance movement behaviors characterized by low AGL (state 1 AGL = 14 m (median); state 2 AGL = 11 m) and two associated with longer‐distance movement behaviors and characterized by higher AGL (state 3 AGL = 108 m; state 4 AGL = 450 m).
  4. Behaviors such as perching and low‐altitude hunting were associated with short‐distance movements in updraft‐poor environments, at higher elevations, and over steeper and more north‐facing terrain. In contrast, medium‐distance movements such as hunting and transiting were over gentle and south‐facing slopes. Long‐distance transiting occurred over the desert habitats that generate the best updraft.
  5. This information can guide management of this species, and our approach provides a template for behavior‐specific habitat associations for other species of management concern.
  相似文献   
97.
98.
While there has been strong support for Amborella and Nymphaeales (water lilies) as branching from basal-most nodes in the angiosperm phylogeny, this hypothesis has recently been challenged by phylogenetic analyses of 61 protein-coding genes extracted from the chloroplast genome sequences of Amborella, Nymphaea, and 12 other available land plant chloroplast genomes. These character-rich analyses placed the monocots, represented by three grasses (Poaceae), as sister to all other extant angiosperm lineages. We have extracted protein-coding regions from draft sequences for six additional chloroplast genomes to test whether this surprising result could be an artifact of long-branch attraction due to limited taxon sampling. The added taxa include three monocots (Acorus, Yucca, and Typha), a water lily (Nuphar), a ranunculid (Ranunculus), and a gymnosperm (Ginkgo). Phylogenetic analyses of the expanded DNA and protein data sets together with microstructural characters (indels) provided unambiguous support for Amborella and the Nymphaeales as branching from the basal-most nodes in the angiosperm phylogeny. However, their relative positions proved to be dependent on the method of analysis, with parsimony favoring Amborella as sister to all other angiosperms and maximum likelihood (ML) and neighbor-joining methods favoring an Amborella + Nymphaeales clade as sister. The ML phylogeny supported the later hypothesis, but the likelihood for the former hypothesis was not significantly different. Parametric bootstrap analysis, single-gene phylogenies, estimated divergence dates, and conflicting indel characters all help to illuminate the nature of the conflict in resolution of the most basal nodes in the angiosperm phylogeny. Molecular dating analyses provided median age estimates of 161 MYA for the most recent common ancestor (MRCA) of all extant angiosperms and 145 MYA for the MRCA of monocots, magnoliids, and eudicots. Whereas long sequences reduce variance in branch lengths and molecular dating estimates, the impact of improved taxon sampling on the rooting of the angiosperm phylogeny together with the results of parametric bootstrap analyses demonstrate how long-branch attraction might mislead genome-scale phylogenetic analyses.  相似文献   
99.
The little-known prepleistocene Lake Indawgyi (Myanmar) is shown to harbour an endemic pelagicEodiaptomus species, described herein. The area around the lake is inhabited by another species in the same genus. Related species occur throughout South-East Asia, and a presumed close relative is endemic to a chain of pre-pleistocene lakes in Celebes.  相似文献   
100.
A major limitation of optimization models of the spine has been the inability to accurately predict trunk muscle co-activity. Antagonist muscle activity is thought to be necessary to maintain adequate levels of spine stability but, in turn, creates increased loading on the spine. It is thus hypothesized that the CNS attempts to optimize the relationship between spine loading and spine stability in determining muscular activation patterns. This study presents an optimization model of the spine in which stability was constrained to target levels predicted from regression equations of independent loading variables. Objective functions were set to either minimize the sum of the cubed muscle forces or minimize the sum of the squared intervertebral forces at the L4-L5 disc level. Results demonstrate that the inclusion of stability constraints in optimization simulations produced realistic predictions of antagonist muscle activity and predictions of spine compression levels that agree more closely with EMG-based estimates, compared to simulations in which stability was unconstrained. It was concluded that spinal stability is a vital consideration for the CNS when dictating trunk muscle recruitment patterns.  相似文献   
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