The Early Evolutionary History and Adaptive Radiation of the Pterosauria

Phylogenetic analyses of early pterosaur species are relatively new and contradictory. However, they imply a similar evolutionary history for early pterosaurs： a large divergence of all major early groups of pterosaurs before the first named pterosaur species appeared in the fossil record. This large, unsampled divergence may be a record of the initial adaptive radiation of the pterosaurs, but a recent comprehensive phylogenetic analysis reconstructs named Triassic pterosaur species grouped together in a monophyletic clade with all other major groups diverging later. Ten patterns that characterize adaptive radiations put forward by Gavrilets and Losos （2009） are assessed for congruence with the comprehensive phylogeny and two previous phylogenies to determine which are consistent with our notions of an adaptive radiation. Of the eight patterns that can be applied to pterosaurs, only six vary between pterosaur phylogenies. Of these six patterns, all apply to the three phylogenies with varying amounts of support. For many patterns, however, the comprehensive phylogeny has a greater magnitude, shorter time span, or is the only topology within which they can be assessed. Pterosaurs are characterized by an adaptive radiation no matter which phylogeny is considered, but congruence with the fossil record increases the support and information content of a phylogeny by reducing the time and area within which to reconstruct evolutionary history.

Adaptive radiation therapy of breast cancer by repeated imaging during irradiation

Breast cancer is the most frequent cancer among females and also a leading cause of cancer related mortality worldwide.A multimodality treatment approach may be utilized for optimal management of patients with combinations of surgery,radiation therapy(RT)and systemic treatment.RT composes an integral part of breast conserving treatment,and is typically used after breast conserving surgery to improve local control.Recent years have witnessed significant improvements in the discipline of radiation oncology which allow for more focused and precise treatment delivery.Adaptive radiation therapy(ART)is among the most important RT techniques which may be utilized for redesigning of treatment plans to account for dynamic changes in tumor size and anatomy during the course of irradiation.In the context of breast cancer,ART may serve as an excellent tool for patients receiving breast irradiation followed by a sequential boost to the tumor bed.Primary benefits of ART include more precise boost localization and potential for improved normal tissue sparing with adapted boost target volumes particularly in the setting of seroma reduction during the course of irradiation.Herein,we provide a concise review of ART for breast cancer in light of the literature.

Effect of Cycloheximide on the Adaptive Response Induced by Low Dose Radiation

Human lymphocytes pre-exposed to 10 mGy or 50 mGy of X-rays become less sensitive to subsequent large dose irradiation, exhibited lower rate of chromosome aberration than expected. This adaptive response could be inhibited by cycloheximide, a protein synthesis inhibitor for successive 2 h period ranging from 0.5h before to 4h after the low dose exposure, indicating that the adaptive response was directly related with the protein synthesis.

An active reflector antenna using a laser angle metrology system

An active reflector is one of the key technologies for constructing large telescopes, especially for millimeter/sub-millimeter radio telescopes. This article in- troduces a new efficient laser angle metrology system for an active reflector antenna on large radio telescopes. Our experiments concentrate on developing an active reflec- tor for improving the detection precisions and the maintenance of the surface shape in real time on the 65-meter prototype radio telescope constructed by Nanjing Institute of Astronomical Optics and Technology （NIAOT; http：//65rn.shao.cas.cn/）. The test results indicate that the accuracy of the surface shape segmentation and maintenance has the dimensions of microns, and the time-response can be on the order of minutes. Our efforts proved to be workable for sub-millimeter radio telescopes.

Dipeptide Formation from Amino Acid Monomer Induced by keV Ion Irradiation: An Implication for Physicochemical Repair by Radiation Itself

An identification of Phe dipeptide from L-phenylalanine monomers after keV nitro- gen and argon ion implantation, by using the HPLC （high performance liquid chromatography） and LC-MS（liquid chromatography mass spectrometer） methods is reported. The results showed a similar yield behavior for both ion species, namely： 1） the yield of dipeptides under alkalescent conditions was distinctly higher than that under acidic or neutral conditions; 2） for different ion species, the dose-yield curves tracked a similar trend which was called a counter-saddle curve. The dipeptide formation may implicate a recombination repair mechanism of damaged biomolecules that energetic ions have left in their wake. Accordingly a physicochemical self-repair mechanism by radiation itself for the ion-beam radiobiological effects is proposed.

Modeling the rail surface unevenness of a high-precision radio telescope

This study proposed a coarse-fine mixed model for describing the rail surface unevenness of an ultra-large fully steerable radio telescope （Qi Tai Telescope） with a diameter of 110 meters. The rail surface unevenness includes information on error arising from two different scales, i.e., the long-period- short-change and the short-period-long-change. Consequently, in this study an idea of a mixed model was proposed, in which trigonometric and fractal functions were, respectively, used to describe infor- mation on error from two scales. Key parameters were determined by using the least squares method and the wavelet transform method, and finally, a specific mathematical expression of the model was obtained by optimization. To validate the effectiveness of the new modeling method, the mixed model was then used to describe the rails of the Green Bank Telescope, the Large Millimeter Telescope, and a radio telescope in Miyun, Beijing. A comparative study revealed that the maximum error was less than 15 %, thus the result was superior to those of existing modeling methods.

Alzheimer's disease and low-dose radiation therapy:A new hope

The concept of low-dose radiation(LDR)-induced hormetic responses was initially observed approximately 70 years ago and systematically reviewed along with the discovery of LDR-induced adaptive responses in a cytogenetic in vitro study in 1980s.By the end of the 1990s,discussions regarding the potential applications of LDRinduced hormesis and adaptive responses for preventing or treating chronic diseases,such as Alzheimer’s disease(AD)had taken place.Until 2016,reports on radiotherapy for the subjects with AD and for genetic AD model mice were published.Subsequently,several preclinical studies with animal models of AD and clinical studies in AD subjects were conducted.A significant milestone was achieved with the online availability of a new Systematic Review based on qualified publications from these preclinical and clinical studies.This mini-review provides a concise historical introduction to LDR-induced hormesis and adaptive responses with discussion of AD radiotherapy with either LDR or relatively high dose radiation.Highlights of this Systematic Review cover promising outcomes,challenges,and new questions,followed by discussion of potential mechanisms.

Monsoon boosted radiation of the endemic East Asian carps

Major historical events often trigger the rapid flourishing of a few lineages,which in turn shape established biodiversity patterns.How did this process occur and develop?This study provides a window into this issue.The endemic East Asian carps(EEAC)dominated the ichthyofauna of East Asia and exhibited a high degree of adaptation to monsoonal river-lake ecosystems.A series of evidence,including ecogeography,phylogenetics,and macroevolution,suggests that the EEAC is a lineage that arose with the East Asian monsoon and thrived intimately with subsequent monsoon activities.We further deduce the evolution of the EEAC and find that a range of historical events in the monsoon setting(e.g.,marine transgression and regression and glacial-interglacial cycle)have further reshaped the distribution patterns of EEAC’s members.Comparative genomics analyses reveal that introgressions during the initial period of EEAC radiation and innovations in the regulation of the brain and nervous system may have aided their adaptation to river-lake ecosystems in a monsoon setting,which boosted radiation.Overall,this study strengthens knowledge of the evolutionary patterns of freshwater fishes in East Asia and provides a model case for understanding the impact of major historical events on the evolution of biota.

Divergent foraging behavior in a hybrid zone： Darwin＇s tree finches （Camarhynchus spp.） on Floreana Island

Hybrid speciation is increasingly recognized as a mechanism for novel evolutionary trajectories. However, we know very little about the ecology of a contact zone that has arisen in sympatry. This study examines the foraging behavior and fitness of two species of Darwin＇s tree finches （Camarhynchus parvulus, C pauper） and hybrid offspring on Floreana Island. Previous study showed that the percentage of hybrids in the tree finch population increased from 19% in 2005 to 41% in 2010, and their body and beak size increased by -5% （parental phenotype did not change）. In 2005-2006, all three tree finch groups （two paren- tal species and hybrid birds） used the same foraging substrate, technique, and height. By 2010-2013, the small tree finch C. par- vulus had changed its foraging technique and the medium tree finch C. pauper had changed its foraging height. Both parental species had higher body condition when foraging at （divergent） mean foraging heights per species but hybrid birds did not. We discuss the implications of conserving forest to facilitate vertical niche expansion and the role of hybridization for genetic persis- tence [Current Zoology 61 （1）： 181-190, 2015].

Stereotactic ablative radiotherapy for hepatocellular carcinoma

Patients with hepatocellular carcinoma(HCC)often present with underlying liver disease and significant comorbidities,limiting treatment tolerance.With the development of improved toxicity models and highly conformal radiation delivery systems,external beam radiotherapy has become a valuable treatment option for liver cancer.Using cutting edge technology,stereotactic ablative radiotherapy(SABR)allows for the delivery of ablative doses in few fractions while sparing uninvolved liver tissue.This approach permits dose escalation and precise tumor targeting with minimal risk of radiation induced liver disease.This review clarifies SABR's role alongside liver-directed treatments such as radiofrequency ablation,transarterial radioembolization,and transarterial chemoembolization in the management of HCC.It also examines the promising potential of SABR combined with immunotherapy to treat advanced HCC.

Comparison of Volumetric and Dosimetric Variations in Nasopharyngeal Carcinoma during Intensity-modulated Radiation Therapy with and without Neoadjuvant Chemotherapy

Objective Patients with nasopharyngeal carcinoma(NPC)undergoing intensity-modulated radiation therapy(IMRT)may experience significant volumetric and dosimetric variations throughout the treatment course.However,neoadjuvant chemotherapy may reduce the extent of these variations.This study was carried out to evaluate volumetric and dosimetric changes in target volumes and organs at risk(OARs)during IMRT in patients with locally advanced NPC who received concurrent chemoradiotherapy(CCRT)alone or in combination with neoadjuvant chemotherapy(NACT).Methods 35 NPC patients were recruited for this study and divided into the NACT(n=15)and CCRT(n=20)groups.Computed tomography(CT)scans were performed before neoadjuvant chemotherapy,before IMRT,before the 24 th fraction of IMRT,and after treatment.The original plan(plan 0)was based on CT images collected before IMRT.Hybrid plan 1(plan 1)and hybrid plan 2(plan 2)were generated by applying the beam configurations of plan0 to the CT scans collected before the 24 th fraction of IMRT and after treatment.Volumetric and dosimetric variations were assessed by comparing the results of plan 0 with those of plan 1 and plan 2.Results In the NACT group,compared with that in plan 0,the primary gross tumor volume(GTVnx)decreased by 33.2%±18.4%and 50.5%±12.6%in plan1 and plan 2,respectively.In the CCRT group,the corresponding reduction rates in plan 1 and plan 2 were 49.4%±8.0%and 77.8%±28.1%,respectively.The volume decrease rates in the NACT group were less than those in the CCRT group(P<0.001).In the NACT group,compared with that of plan0,the dose to 95%of the volume(D95)for the planning target volume of the primary tumor(PTVnx)decreased by 1.0%±0.7%and 0.6%±0.6%in plan 1 and plan 2,respectively.In the CCRT group,the corresponding decrease rates in plan 1 and plan 2 were 4.2%±3.8%and 6.1%±6.3%,respectively.The decrease rate of D95 for PTVnx in the NACT group was less than that in the CCRT group(P<0.001).Similar results among the plans were found in terms of D99,Dmean,V93 for PTVnxand PTVnd,and Dmeanfor the parotid glands.Conclusion Neoadjuvant chemotherapy reduces the extent of volumetric and dosimetric variations in target volumes and OARs during IMRT and,thus,helps achieve better target volume coverage,protects adjacent important structures,and minimizes unnecessary replanning during radiotherapy.

Universal soldier： Pseudomonas aeruginosa -- an opportunistic generalist

The opportunistic pathogen Pseudomonas aeruginosa commonly causes chronic and ultimately deadly lung infections in individuals with the genetic disease cystic fibrosis （CF）. P. aeruginosa is metabolically diverse; it displays a remarkable ability to adapt to and successfully occupy almost any niche, including the ecologically complex CF lung. These P. aeruginosa lung infections are a fascinating example of microbial evolution within a ＂natural＂ ecosystem. Initially, P. aeruginosa shares the lung niche with a plethora of other microorganisms and is vulnerable to antibiotic challenges. Over time, adaptive evolution leads to certain commonly-observed phenotypic changes within the P. aeruginosa population, some of which render it resistant to antibiotics and apparently help it to out-compete the other species that co-habit the airways. Improving genomics techniques continue to elucidate the evolutionary mechanisms of P. aeruginosa within the CF lung and will hopefully identify new vulnerabilities in this robust and versatile pathogen.

Phenotypic plasticity Gasterosteus aculeatus ence in captivity of the threespine stickleback telencephalon in response to experi-

Threespine stickleback were used to examine phenotypic plasticity of telencephala in relation to inferred ecology. Fish from derived, allopatric, freshwater populations were sampled from three shallow, structurally complex lakes with ben- thic-foraging stickleback （benthics） and from three deep, structurally simple lakes with planktivores （limnetics）. The telencepha- Ion of specimens preserved immediately after capture （field-preserved）, field-caught fish held in aquaria for 90 days （lab-held）, and lab-bred fish from crosses and raised in aquaria were compared. Field-preserved sea-run （ancestral） stickleback were col- lected from two separate sites, and parents of lab-bred sea-run stickleback were collected from one of these sites. In field-preserved and lab-held fish, the telencephala of limnetics exhibited triangular dorsal shape, while those of benthics and sea-run fish had rounder shapes. No such pattern was detected in lab-bred fish. Within each treatment type, benthics had larger relative telencephalon sizes, using overall brain size as the covariate, than limnetics. Among field-preserved samples, sea-run fish had smaller telencephalon sizes than lake fish. Intra-population analyses of lake samples showed that field-preserved fish consis- tently had larger relative telencephalon sizes than lab-bred fish. The opposite was true of the sea-run population. In a separate study using one benthic population and one limnetic population, samples were preserved in the field immediately or held in the lab for 30, 60, and 90 days before they were sacrificed. In both populations, the telencephalon shapes of lab-held fish were similar to those of field-preserved fish but became progressively more like lab-bred ones over 90 days. In contrast, relative telencephalon size decreased dramatically by 30 days after which there was littie change. In freshwater threespine stickleback, the telencephalon exhibits considerable phenotypic plasticity, which was probably present in the ancestor [Current Zoology 58 （1）： 189-210, 2012].

Inducible competitors and adaptive diversification

Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and the formation of new spe- cies-stems from divergent natural selection, often arising from competitive interactions. Although increasing evidence suggests that phenotypic plasticity can facilitate this process, it is not generally appreciated that competitively mediated selection often also provides ideal conditions for phenotypic plasticity to evolve in the first place. Here, we discuss how competition plays at least two key roles in adaptive diversification depending on its pattern. First, heterogenous competition initially generates heterogeneity in resource use that favors adaptive plasticity in the form of ＂inducible competitors＂. Second, once such competitively induced plas- ticity evolves, its capacity to rapidly generate phenotypic variation and expose phenotypes to alternate selective regimes allows populations to respond readily to selection favoring diversification, as may occur when competition generates steady diversifying selection that permanently drives the evolutionary divergence of populations that use different resources. Thus, competition plays two important roles in adaptive diversification---one well-known and the other only now emerging--mediated through its effect on the evolution ofphenotypic plasticity

Adaptive Dose-Compensation Technique for Image-Guided Radiotherapy of Prostate Cancer

Background: For image-guided radiotherapy(IGRT) of prostate cancer, the current standard is online image guidance which can effectively correct setup errors and inter-fraction rigid organ motion. However, planning margins are still necessary for deformation and intra-fraction motion. Objective: This paper aims to investigate an adaptive planning technique incorporating offline dose feedback to manage interfraction motion and residuals from online corrections. Methods:Repeated CT scans from 28 patients were studied. Online IG was simulated by matching center-of-mass of prostate. A seven-beam IMRT plan with zero margins was designed for each patient. Dose distribution at each fraction was evaluated based on actual target and OARs from that fraction. Cumulative dose was calculated using deformable registration and compared to initial plan. If deviation exceeded pre-defined 2% threshold in prostate D99 an adaptive planning technique called dose compensation was invoked, in which cumulative dose was fed back to the planning system and dose deficit was made up through boost radiation in future fractions through IMRT. Results: If 2% under-dose was allowed at the end of course, then 11 patients failed. If the same criteria was assessed at the end of each week(every 5 fractions), then 14 patients failed. The average dose deficit for these 14 patients was4.4%. They improved to 2% after weekly compensation. 10(out of 14) patients passed criterion after weekly dose compensation; 3 failed marginally; 1 failed significantly(10% deficit). A more aggressive compensation frequency(every 3 fractions) could reduce the dose deficit to the acceptable level for this patient. The doses to OARs were not significantly different from online IG only without dose compensation.Conclusion: We demonstrated an offline dose compensation technique in prostate IGRT which can effectively account for residual uncertainties uncorrectable in online IG. Dose compensation allows further margin reduction and critical organs sparing.