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In a recent issue of this journal (Volume 15, Number 4, Fall 1990), Susan Sterett examined the role of the Law Commission in the development of English administrative law. She suggested that the Commission mimicked a “peak association” and adopted an “idiom of legalism” in order to justify its reform proposals. This comment disagrees with Sterett on three grounds. First, the role and constitutional position of the Commission is far more complex than Sterett suggests, and this affects the way in which the Commission works. Second, judges and academic lawyers were central to the reform of substantive principles of judicial review in the 1960s and 1970s, making it unnecessary for the Law Commission to act in this field. Finally, it is wrong to ignore the fact that much administrative law occurs outside the judicial review procedure.
To determine the clinical diagnoses associated with the National Healthcare Safety Network (NHSN) pneumonia (PNEU) or lower respiratory infection (LRI) surveillance events
Retrospective chart review
A convenience sample of 8 acute-care hospitals in Pennsylvania
All patients hospitalized during 2011–2012
Medical records were reviewed from a random sample of patients reported to the NHSN to have PNEU or LRI, excluding adults with ventilator-associated PNEU. Documented clinical diagnoses corresponding temporally to the PNEU and LRI events were recorded.
We reviewed 250 (30%) of 838 eligible PNEU and LRI events reported to the NHSN; 29 reported events (12%) fulfilled neither PNEU nor LRI case criteria. Differences interpreting radiology reports accounted for most misclassifications. Of 81 PNEU events in adults not on mechanical ventilation, 84% had clinician-diagnosed pneumonia; of these, 25% were attributed to aspiration. Of 43 adult LRI, 88% were in mechanically ventilated patients and 35% had no corresponding clinical diagnosis (infectious or noninfectious) documented at the time of LRI. Of 36 pediatric PNEU events, 72% were ventilator associated, and 70% corresponded to a clinical pneumonia diagnosis. Of 61 pediatric LRI patients, 84% were mechanically ventilated and 21% had no corresponding clinical diagnosis documented.
In adults not on mechanical ventilation and in children, most NHSN-defined PNEU events corresponded with compatible clinical conditions documented in the medical record. In contrast, NHSN LRI events often did not. As a result, substantial modifications to the LRI definitions were implemented in 2015.
The degree of perceived taxonomic change in various lineages may be directly related to their general morphologic complexity: more complex forms appear to change more rapidly. “Rates of evolution” as customarily reported by paleontologists may therefore be a poor indication of evolutionary changes in the underlying genome. Two approaches were used to examine this problem. (1) We have estimated the degree of morphologic complexity by using the number of descriptive terms per genus, and per family, for 12 major groups of animals. Three general levels of complexity occur: (i) gastropods, bivalves and ectoprocts have relatively few terms; (ii) echinoids, foraminiferans, ostracodes, nautiloids, corals, trilobites, and brachiopods have an intermediate number of terms; (iii) mammals and ammonoids appear to have a relatively large number of terms. These 3 levels of complexity also increase in rate of taxonomic turnover; i.e., an increasing rate of evolution. (2) Using a cluster analysis based on morphologic similarity, we grouped 200 lineages of a computer-generated phylogenetic sequence according to 4 phenetic bases: 3, 5, 10 and 20 morphologic traits. Groups based on a few characters are longer lived and are commonly polyphyletic in comparison with groups based on many characters. In both the real world and the computer simulation, the bias of differential morphologic complexity may account for the observation that “only complicated animals evolve.” Most paleontologic studies of the “rate of evolution” may tell us more about morphologic complexity than about evolutionary rates of genomes.
Poecilozonites (Gastrelasmus) is an important component of the endemic land snail fauna of Pleistocene Bermuda. The type species P. circumfirmatus Redfield usually occurs in sympatry with its congener P. discrepans Pfeiffer, though each species is found alone at several localities. The species are less alike morphologically where they occur together than where they are allopatric. This allopatric convergence and sympatric divergence strongly suggests the biological interaction known as character displacement, often documented for living populations. The relatively complete fossil record of Bermuda offers advantages for studying this phenomenon. Collections can be made from a variety of microhabitats occupied through time. Statistical analysis of 1,600 individuals collected from more than 100 localities indicates that interspecific variation is primarily a function of the presence or absence of a congener and depends to a lesser degree on microhabitat. P. circumfirmatus undergoes a smaller morphological change between allopatry and sympatry than does P. discrepans. Study of relative abundances suggests that P. discrepans may have been competitively inferior, though no functional bases for differences between the species are known.
The history of life is replete with apparent order. Much of this order may reflect the deterministic causes conventionally invoked, but we cannot be sure until we measure and subtract the order that arises in simple random systems. Consequently, we have constructed a random model that builds evolutionary trees by allowing lineages to branch and become extinct at equal probabilities. We proceed by dividing our simulated tree into clades and by comparing their sizes and shapes with the patterns exhibited by “real” clades as recorded by fossils.
We regard the similarity of real and random clades as the outstanding result of this comparison. In both real and random systems, extinct clades arising after an “ecological barrel” had been filled have their maximum diversity at the midpoint of their duration; clades arising during the initial “filling” reach an earlier climax during this preequilibrial period of rapid diversification. However, some potential differences also emerge. Clades still living are much larger than extinct clades. We may attribute this to the morphological superiority of survivors, but we can also simulate it in a model that chooses the originators of clades at random. Real clades undergo greater fluctuations in diversity than do random clades, but the effect is not marked.
We present a quantitative method for describing how heterochronic changes in ontogeny relate to phyletic trends. This is a step towards creating a unified view of developmental biology and evolutionary ecology in the study of morphological evolution. Using this representation, we obtain a greatly simplified and logical scheme of classification. We believe that this scheme will be particularly useful in studying the data of paleontology and comparative morphology and in the analysis of processes leading to adaptive radiation. We illustrate this scheme by examples drawn from the literature and our own work.
We assessed the impact of a reflex urine culture protocol, an intervention aimed to reduce unnecessary urine culturing, in intensive care units at a tertiary care hospital. Significant decreases in urine culturing rates and reported rates of catheter-associated urinary tract infection followed implementation of the protocol.
Hematologic malignancies make up about 9% of the new cancer cases in the USA in 2013. Of the new hematologic cancer cases, approximately 53% were lymphoma, 32% were leukemia, and 15% were myeloma. The management of pain in hematologic cancers presents a constellation of problems that are distinctly different from those associated with solid tumors. We will review four cases of patients who presented with pain associated with hematologic cancer that illustrate the unique complexity and breadth of the problems to be addressed. We will then discuss considerations that should be taken that affect the assessment of risks and the selection of analgesic treatment, and the monitoring of clinical response.
Previously published guidelines are available that provide comprehensive recommendations for detecting and preventing healthcare-associated infections (HAIs). The intent of this document is to highlight practical recommendations in a concise format designed to assist acute care hospitals in implementing and prioritizing their catheter-associated urinary tract infection (CAUTI) prevention efforts. This document updates “Strategies to Prevent Catheter-Associated Urinary Tract Infections in Acute Care Hospitals,” published in 2008. This expert guidance document is sponsored by the Society for Healthcare Epidemiology of America (SHEA) and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise. The list of endorsing and supporting organizations is presented in the introduction to the 2014 updates.
Previously published guidelines are available that provide comprehensive recommendations for detecting and preventing healthcare-associated infections (HAIs). The intent of this document is to highlight practical recommendations in a concise format designed to assist acute care hospitals in implementing and prioritizing their catheter-associated urinary tract infection (CAUTI) prevention efforts. This document updates “Strategies to Prevent Catheter-Associated Urinary Tract Infections in Acute Care Hospitals,” published in 2008. This expert guidance document is sponsored by the Society for Healthcare Epidemiology of America (SHEA) and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America (IDSA). the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise. The list of endorsing and supporting organizations is presented in the introduction to the 2014 updates.
The synaptic ribbon is a unique presynaptic structure with an intricate morphology in photoreceptors. Because of the resolution limit in conventional fluorescence microscopy, investigating ribbon protein locations has been challenging, especially in the early development stages of model animals. Here, we used stimulated emission depletion microscopy, a super-resolution imaging technique, to look at retina sections in 4 days post-fertilization (dpf) zebrafish. We observed that in photoreceptor cells, RIBEYE and RIM2 are expressed along the synaptic ribbon, with RIM2 consistently located inside of the horseshoe-shaped synaptic ribbon structure with RIBEYE located on the outside. The L-type calcium channel subunit, CACNA1F, exhibited small spot-like staining beneath the RIM2 and RIBEYE structures. Using morpholino antisense oligonucleotides to knock down RIBEYE expression, we observed fewer and shorter ribbons in the photoreceptor outer plexiform layers of 4 dpf fish retina as well as a reduction in RIM2 expression. The clustering of CACNA1F in these blind fish was no longer observed, but instead showed a diffuse expression in the photoreceptor terminal.
A subsemigroup S of a semigroup Q is a left (right) order in Q if every q ∈ Q can be written as q = a*b(q = ba*) for some a, b ∈S, where a* denotes the inverse of a in a subgroup of Q and if, in addition, every square-cancellable element of S lies in a subgroup of Q. If S is both a left order and a right order in Q, we say that S is an order in Q. We show that if S is a left order in Q and S satisfies a permutation identity xl…xn = x1π…xnπ where 1 < 1π and nπ<n, then S and Q are commutative. We give a characterisation of commutative orders and decide the question of when one semigroup of quotients of a commutative semigroup is a homomorphic image of another. This enables us to show that certain semigroups have maximum and minimum semigroups of quotients. We give examples to show that this is not true in general.