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The conflict theory is the only hypothesis to have attracted any critical attention for the evolution of genomic imprinting. Although the earliest data appeared supportive, recent systematic analyses have not confirmed the model's predictions. The status of theory remains undecided, however, as post-hoc explanations can be provided as to why these predictions are not borne out.
OBJECTIVES: Hypervirulent ceftazidime/avibactam (CAZ/AVI)-resistant Klebsiella pneumoniae (Kp) has emerged; however, its dynamic within-host evolution and competitive features are uncharacterized. This study aimed to clarify the systematic microevolution characteristics of the rapid transformation of blaKPC variants during long-term infection. METHODS: Thirty-nine Kp strains were isolated from a single patient with severe recurrent osteomyelitis during a 2-year period. Whole-genome sequencing and in vitro evolution assay was performed. Microbiological characteristics were examined through antimicrobial susceptibility testing, plasmid stability, growth curve, in vitro competition and Galleria mellonella larvae lethality assays. RESULTS: Among all the clinical Kp isolates, 37 were carbapenem-resistant Kp (CRKP), including 25 CAZ-/AVI-resistant Kp. All isolates belonged to the ST11-K47. During in vivo evolution, the blaKPC variant and its amplification emerged. Twenty-four isolates (24/39, 61.5%) harboured a novel blaKPC variant, blaKPC-144. All five Kp isolates carried blaKPC-2 in 2021. Surprisingly, 24 blaKPC-144-harbouring isolates (70.6%, 24/34) and 10 blaKPC-2-harboring isolates were identified in 2023, indicating rapid changing of blaKPC. Kp4 carried two copies of blaKPC-2, and Kp10-1 exhibited a 1.94-fold increase in the blaKPC-144 copy number. Similarly, in vitro, the blaKPC copy number increased upon exposure to low CAZ/AVI concentrations. However, at higher concentrations (4/1 mg/L), the blaKPC copy number increased significantly, and blaKPC mutations emerged simultaneously. The competition assay indicated that the blaKPC-144-harboring isolates exhibited a superior competitive capacity. CONCLUSIONS: The blaKPC amplification and mutation emerged simultaneously or sequentially during in vivo and in vitro evolution. Kp isolates harbouring blaKPC-144, conferring resistance to CAZ/AVI, exhibited a competitive advantage, promoting the rapid replacement of blaKPC-2.
Systematic relationship among the 12 species of the Drosophila virilis species group, and Drosophila robusta, were investigated by the use of two-dimensional electrophoresis (2-DE). A total of 389 protein characters (about 200 loci) were scored and analyzed both phylogenetically and phenetically. The resulting phylogeny was found to be largely concordant with the current views of evolution among these species based on other independent morphological, chromosomal, electrophoretic, and immunological data sets, although some notable differences were observed. The 2-DE data also appeared to be useful for constructing a molecular clock to date the absolute times of divergence among the species. It appears from this analysis that the evolution of the major clades within the species group occurred about 20 million years ago. Previous suggestions that the rate of molecular evolution was different between the virilis and montana phylads was not confirmed. The technique of 2-DE seems to be an excellent tool for reconstructing phylogenies and should be particularly valuable for examining relatively closely related species.
Darwin's evolutionary theory was the starting point for ethology, associated with an impact on scientific psychiatry. Psychiatry and ethology have common scientific and methodological prerequisites: inductive and deductive methods and "gestalt theory" as a basis for observing and describing behaviour patterns with subsequent causal analysis. There have been early endeavours to anchor ethological thinking in psychiatry but this tendency did not prevail for the following reasons: on the one hand, the methodology of ethology was immature or not applicable to man, whereas on the other hand the dominating experiential phenomenological school of Karl Jaspers and Kurt Schneider stressed the privileged position of human thinking, perception, and feeling. These fundamental categories of human existence did not appear amenable to any causal ethological analysis. Psychiatry and evolutionary biology were linked in an atrocious manner during the Nazi regime, both being abused for propaganda purposes and genocide. More recently, there is a "reconciliation" of both disciplines. In psychiatric nosology, operational, behaviour-oriented diagnostic systems have been introduced; ethology has opened up for theories of learning; new subsections like human ethology and sociobiology have evolved. The seeming incompatibility of (behavioural) biological psychiatry and experiential phenomenological psychopathology may be overcome on the basis of Konrad Lorenz' evolutionary epistemology. The functional analysis of human feeling and behaviour in psychotic disorders on the basis of Jackson's theory of the evolution and dissolution of the nervous system may serve as an example. The significance of an "ethological psychiatry" for diagnostic and therapeutical processes of psychiatric disorders derive from prognostic possibilities and the analysis of non-verbal communication in therapist-patient-interactions, but have not yet been systematically investigated.
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From a group of 9 patients suffering from progressive supranuclear palsy 11 polygraphic records and 6 tests with probenecid have been made. The changes in sleep can be correlated with the severity of the clinical picture and the stage of evolution of the disease. They support the hypothesis of a systematic progression of the lesions in the hypnogenic structures of the brain stem.
1. Bile salts of the sturgeons Acipenser guldenstaedti Brandt, Acipenser stellatus Pall and Huso huso L. and of the paddlefish Polyodon spathula Walbaum are shown to be closely similar, consisting mainly of taurocholate with minor amounts of tauroallocholate and the monosulphates of bile alcohols. The bile alcohols, comprising less than 10% of the bile salts, are mixtures with high proportions of substances resembling C(27) tetrols and of C(27) pentols, including 5beta-cyprinol and (probably) 5alpha-cyprinol. 2. 5beta-Cyprinol (3alpha,7alpha,12alpha,26,27-pentahydroxy-5beta-cholestane) was made from cholic acid via 3alpha,7alpha,12alpha-triacetoxy-5beta-cholan-24-ol in an overall yield of about 0.8%. 3. The chemical nature of chondrostean bile salts agrees with the systematic position of the fishes and suggests further correspondence between evolution at the morphological and molecular levels.
Training supervision is a longitudinal, nonclinically focused personal relationship between a faculty member and a resident for exploring the latter's professional development. In the authors' program the training supervisor meets with the supervisee monthly over the 3-year residency. The training supervisor's role is that of a nonevaluative senior colleague who orients and advises the resident and systematically reviews training progress and problems. The authors discuss the evolution of the training supervision concept, explore potential role conflicts for the training supervisor, who may serve other functions in the residency of the supervisee, and present positive and negative resident and faculty evaluations of their program.
Hamster fibroblasts transformed in vivo by the SV40 virus (TSV5Cl2) induce tumours when injected into adult hamsters and antibodies present in sera of tumour-bearing animals are used to demonstrate the presence of the antigens specific for the viral transformation. These tumours are a very useful tool in studying the evolution of the immune response during the tumour growth. A systematic histological examination of the spleen, thymus and lymph nodes was undertaken and the results thus obtained were correlated with a parallel study of the cells of the peritumoral region, the thymus and the spleen by immunofluorescence using antisera of different specificities. We were able to show that the plasma cells which make up the early peritumoral reaction and the lymphoblasts found later in spleen and thymus both synthesize antibodies directed against virus induced antigens. Circulating antibody directed against the same antigens is first detected at/or about the time that the peritumoral plasma cell reaction disappears and increases progressively as tumour weight increases.
A new case of asymptomatic thymolipoma in a 4.5 years old girl is reported. It was discovered during systematic medical investigation. Its radiological characteristics and the lack of evolutivity made the authors suspect the diagnosis before operating. A total surgical extraction of the 300 g weighing tumor was performed through a right thoracotomy. No complication occurred in the post-operative time. Others authors already indicated the scarcity of this affection (less than 10 cases in children) as well as the special radiological characteristics of this tumor and the noticeable clinical tolerance often despite a large bulk. Histologically the tumor is made of an infiltrating of the normal thymic tissue by proliferating adipose adulte cells, the benignity of which is demonstrated by the evolution. In this study a differential diagnosis between thymolipoma and other mediastinal tumors is made and also some pathogenic assessments. Surgery always is required for treatment.
In complex traffic systems, driving risk often evolves in a continuous and progressive manner prior to crash occurrence. How to effectively represent and analyze such latent risk states remains a central challenge in traffic safety research. In recent years, risk field-based approaches have introduced spatial and spatiotemporal continuous modeling paradigms, providing new perspectives for characterizing the distribution of traffic risk and its dynamic evolution. Motivated by the rapid growth of this research area and the lack of a systematic synthesis, this paper presents a comprehensive review of studies applying risk field theory to driving safety and traffic risk analysis. Following the PRISMA guidelines, relevant literature was collected through multi-database searches and analyzed using a combination of bibliometric analysis and qualitative review. The review systematically summarizes the theoretical foundations, modeling elements, data sources, analytical methods, and application domains of risk field-related research. Particular attention is given to studies that conceptualize traffic risk as a continuous field, complemented by a broader review of traffic risk factor literature to identify key elements and analytical dimensions involved in risk field modeling. On this basis, the paper synthesizes research progress in major application areas, including traffic safety state representation, driving behavior analysis, traffic conflict assessment, and autonomous driving and human-machine cooperative systems. Differences and commonalities among existing studies are compared in terms of modeling strategies, data support, and application scenarios. Through this systematic review, the paper clarifies the main research themes and methodological trends of risk field-based studies, providing a structured framework for understanding the evolution and application of this approach and offering methodological insights for risk perception modeling and safety-oriented decision support in intelligent transportation systems (ITS).
I here introduce a free fitness function in population biology, which monotonically increases with time and takes its maximum at the evolutionary equilibrium. By suitably defining an "index" for each state, the free fitness is expressed as the average index plus an entropy term. In many cases, the index has a biologically clear meaning, such as the logarithmic population mean fitness. The technique is applicable to any Markov process model (either continuous or discrete) with a positive steady state. I discuss four examples from various branches of population biology: (1) one-locus-two-allele system of population genetics with mutation, selection, and random genetic drift; (2) evolutionary dynamics of quantitative characters; (3) a molecular evolution model; and (4) an ecological succession model. Introducing free fitness clarifies the balance between systematic forces (e.g. natural selection or successional trend toward the climax) and disturbing processes (e.g. random drift).
Vertebrate viviparity (live-bearing reproduction), placentation, and placentotrophy are widely assumed to have evolved as three successive, gradualistic transformations. From empirical data and predictive tests on lizards and snakes, this paper indicates that placentae and a degree of placentotrophy have evolved repeatedly as necessary correlates of viviparity, not as subsequent modifications. In addition, information derived from studies of anatomy, physiology, biogeography and systematics is used to evaluate new saltationist and punctuated equilibrium models for the evolution of viviparity. Phylogenetic reconstruction reveals that more than 100 squamate clades have made the transition to viviparity and placentation. However, various phenotypic intermediates postulated by the gradualistic model are either scarce or unrepresented among known forms, including those in which viviparity has evolved at specific and subspecific levels. Evolution in squamates seems to have produced a dichotomy between two evolutionarily stable patterns: (i) retention of weakly shelled or shell-free eggs to term (viviparity), with development of fully functional placentae; and (ii) deposition of shelled eggs at or near the limb bud stage of development (typical oviparity). Conflicting functional demands placed on eggshell morphology may constrain establishment of prolonged, oviparous egg-retention as a viable, historically stable pattern. Alternatively, the costs of prolonged egg-retention associated with decreased female mobility or decreased fecundity may exceed the benefits in oviparous forms.
Despite extensive studies on the ecology and evolution of the freshwater microcrustacean Daphnia, there is little understanding of the evolutionary history of the genus. Past attempts at reconstructing phylogenetic relationships among Daphnia species have been highly controversial, mainly because of the poor taxonomy of the genus. However, following a revised taxonomy of the daphniid fauna of North America, we conducted a comprehensive appraisal of systematic relationships within the genus through the analysis of sequence diversity in 503 b.p. of the 12S rRNA gene of the mtDNA. The large sequence divergence among its 34 North American members indicates that the genus Daphnia originated during the Mesozoic, even though many lineages exhibit extreme morphological stasis. Results from both cladistic and phenetic analyses indicate the presence of three subgenera comprised of 15 species complexes. Only four of these lineages have shown active speciation over the past 3 Ma, suggesting that cladogenesis in the genus has been constrained. Our study also reveals that interspecific hybridization occurs between taxa which show very large sequence divergence (up to 14%), suggesting that reproductive isolation within the genus evolves slowly.
Concern about the safety of genetically engineered organisms in the environment arises from the undesirable results of earlier new technologies and introduced organisms. Progress towards safe release is complicated by the varied views of a diverse society, confusion of process and product, problems with existing methods, and the lack of practical experience with real releases. No categorically safe novel organisms exist, but a progressive series of releases should allow risks to be systematically reduced.
Quality assessment and assurance in the intensive care unit require systematic monitoring and evaluation of patient care and its outcome. For analysis of these activities, data must be organized to reflect changes in such factors as patient types, ages, and lengths of stay. A model was developed to group data from the Cleveland Clinic Hospital medical intensive care unit into structural, process, and outcome categories. Development and application of the model are described.