bluuebunny/crossref_metadata_2025_split huggingface dataset:
Controlling confounding of treatment effects in administrative data in the presence of time‐varying baseline confounders
Authors: Gilbertson David T. , Bradbury Brian D. , Wetmore James B. , Weinhandl Eric D. , Monda Keri L. , Liu Jiannong , Brookhart M. Alan , Gustafson Sally K. , Roberts Tricia , Collins Allan J. , Rothman Kenneth J. 
Published: November 2015

AbstractPurposeConfounding, a concern in nonexperimental research using administrative claims, is nearly ubiquitous in claims‐based pharmacoepidemiology studies. A fixed‐length look‐back window for assessing comorbidity from claims is common, but it may be advantageous to use all historical claims. We assessed how the strength of association between a baseline‐identified condition and subsequent mortality varied by when the condition was measured and investigated methods to control for confounding.MethodsFor Medicare beneficiaries undergoing maintenance hemodialysis on 1 January 2008 (n = 222 343), we searched all Medicare claims, 1 January 2001 to 31 December 2007, for four conditions representing chronic and acute diseases, and classified claims by number of months preceding the index date. We used proportional hazard models to estimate the association between time of condition and subsequent mortality. We simulated a confounded comorbidity–exposure relationship and investigated an alternative method of adjustment when the association between the condition and mortality varied by proximity to follow‐up start.ResultsThe magnitude of the mortality hazard ratio estimates for each condition investigated decreased toward unity as time increased between index date and most recent manifestation of the condition. Simulation showed more biased estimates of exposure–outcome associations if proximity to follow‐up start was not considered.ConclusionsUsing all‐available claims information during a baseline period, we found that for all conditions investigated, the association between a comorbid condition and subsequent mortality varied considerably depending on when the condition was measured. Improved confounding control may be achieved by considering the timing of claims relative to follow‐up start. Copyright © 2015 John Wiley & Sons, Ltd.
Evolution of a protein folding nucleus
Authors: Xia Xue , Longo Liam M. , Sutherland Mason A. , Blaber Michael 
Published: November 2015

AbstractThe folding nucleus (FN) is a cryptic element within protein primary structure that enables an efficient folding pathway and is the postulated heritable element in the evolution of protein architecture; however, almost nothing is known regarding how the FN structurally changes as complex protein architecture evolves from simpler peptide motifs. We report characterization of the FN of a designed purely symmetric β‐trefoil protein byϕ‐value analysis. We compare the structure and folding properties of key foldable intermediates along the evolutionary trajectory of the β‐trefoil. The results show structural acquisition of the FN during gene fusion events, incorporating novel turn structure created by gene fusion. Furthermore, the FN is adjusted by circular permutation in response to destabilizing functional mutation. FN plasticity by way of circular permutation is made possible by the intrinsic C3cyclic symmetry of the β‐trefoil architecture, identifying a possible selective advantage that helps explain the prevalence of cyclic structural symmetry in the proteome.
PSM auditing: Thinking beyond compliance
Authors: Gill Stephen 
Published: November 2015

The process safety management (PSM) rule requires a “compliance audit” at least every 3 years. This description implies that the purpose of the audit is to ensure that legal requirements are met. Thoughtful companies recognize that meeting the minimum legal requirements may not be sufficient, and also audit for conformance with their internal company standards and procedures. However, in audit programs designed to check compliance with either legal or legal + internal requirements, there is an implicit assumption that conformance will result in an acceptable process safety performance. In other words, if all of the “inputs” are right (i.e., there is compliance with the standards and procedures), then process safety is being managed effectively—and the desired “outputs” will follow. This assumption may not be valid! In reality, managing process safety requires the meshing or connecting of several related work processes or activities in order to effectively deliver the desired results. Checking each activity for compliance with standards does not necessarily ensure that the sum of the connected activities is delivering what was intended.Take, for example, the identification and control of major risk scenarios. The PSM intention is that risk scenarios are identified in either the initial Process Hazard Analysis (PHA) or subsequent revalidation, sufficient controls are provided to meet the corporate risk criteria, the controls are maintained throughout the operating life, the operating, technical, and management teams are trained in and understand the scenarios and the scenarios are well documented in the operating procedures. Compliance auditing typically checks that all of the individual activities are “compliant” (PHA conducted on time and actions closed, trip system testing completed per schedule, training records complete, operating procedures updated on time, etc.). Such an approach does not typically track that the content is carried consistently through the collection of processes, and that the knowledge and controls for the identified scenarios are in place and robust.This article proposes an audit approach which checks both that the organization is compliant with the prescribed activities and procedures, and that the activities and procedures are effectively delivering the intended results. The main focus is on applying this approach to the aspects of PSM that address specific risk scenarios and their associated controls. © 2015 American Institute of Chemical Engineers Process Saf Prog 35: 295–299, 2016
Efficacy of selected food‐safe compounds to prevent infestation of the ham mite, Tyrophagus putrescentiae (Schrank) (Acarina: Acaridae), on southern dry‐cured hams
Authors: Abbar Salehe , Amoah Barbara , Schilling M Wes , Phillips Thomas W 
Published: November 2015

AbstractBACKGROUNDTyrophagus putrescentiae (Schrank) is a serious mite pest of dried meats and cheeses. Infestations of T. putrescentiae are controlled with the fumigant methyl bromide, which is an ozone‐depleting substance and is currently being banned in most countries. Effective alternatives to methyl bromide are needed. The objective of this research was to use laboratory assays to investigate the effectiveness of food‐safe compounds for preventing infestation of T. putrescentiae on dry‐cured hams.RESULTSHam pieces dipped in solutions of either propylene glycol (1,2‐propanediol), lard, ethoxyquin or butylated hydroxytoluene prevented or significantly reduced mite population growth. Behavioral assays revealed that more mites oriented to the untreated control ham cubes, and more eggs were laid on these untreated ham cubes, compared with cubes treated with various dips. Our results also indicated that a combination of carrageenan + propylene glycol alginate + 40% propylene glycol was effective in reducing mite numbers on whole aging hams compared with untreated whole hams.CONCLUSIONSSeveral food‐safe compounds can prevent infestation of T. putrescentiae on dry‐cured hams and may represent alternatives for managing this pest. © 2015 Society of Chemical Industry
Photoluminescence dynamics of formation of electron‐hole droplets in a GaAs/AlAs type‐II superlattice
Authors: Furukawa Yoshiaki , Nakayama Masaaki 
Published: November 2015

AbstractWe report photoluminescence (PL) dynamics at 10 K in a GaAs/AlAs type‐II superlattice, in which electrons (holes) are confined in the AlAs (GaAs) layer, focusing on dynamical formation of electron‐hole droplets (EHDs) from electron‐hole plasma (EHP) in a gas phase. It was found from systematic time‐resolved PL (TRPL) spectra that only a broad PL band attributed to the EHP is observed in an initial time region within ∼0.4 ns, whereas the exciton‐ and biexciton‐PL bands appear and grow with time after ∼0.7 ns. In the time region after ∼14 ns, the line shape of the broad PL band hardly depends on time; namely photogenerated carriers are in quasi‐thermal equilibrium. The stability energy of the EHD was estimated to be ∼3.1 meV relative to the biexciton energy from the line‐shape analysis of the TRPL spectrum at 30 ns. Consequently, the above temporal changes of the line shape of the broad PL band demonstrate the dynamical transition from the EHP to the EHD during the PL decay process. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Robust compensation of time delayed plant by continuous‐time high frequency periodic controller with negligible output ripples
Authors: Chakraborty Arindam , Dey Jayati 
Published: November 2015

SummaryThe present work addresses the problem of ensuring robust stability to time delayed plants, compensated with continuous‐time high frequency periodic controller. An efficient design methodology is proposed to synthesize the periodic controller for robust compensation of time delayed linear time‐invariant plants. The periodic controller, by virtue of its loop zero‐placement capability, is shown to achieve superior gain as well as phase/delay margin compensation, especially for non‐minimum phase plants having right half plane poles and zeros in close vicinity to each other. The periodic controller is considered in the observable canonical form which results in realizable bounded control input as well as ensuring insignificant periodic oscillations in the plant output. As a consequence, this paper, furthermore, establishes the fact that the periodic controller designed and synthesized with the proposed methodology can be implemented in real‐time with an assurance of model matching and robust zero‐error tracking. Simulation and experimental results are illustrated to establish the veracity of the claims. The closed‐loop system comprising of time‐delayed linear time‐invariant plant with the periodic controller is analyzed employing the averaging principle and presented here explicitly in a meticulous approach. Copyright © 2015 John Wiley & Sons, Ltd.
Jitter floor elimination for blind feedforward/feedback symbol‐timing recovery exploiting the extended zero‐crossing property
Authors: Gappmair Wilfried , Cioni Stefano , Corazza Giovanni E. , Koudelka Otto 
Published: November 2015

SummaryCarrier‐blind and non‐data‐aided recovery of the symbol timing is of paramount importance in digital receivers, that is, detailed knowledge about carrier frequency and phase or any pilot sequence is not necessary for proper operation. In this context, feedforward algorithms are particularly helpful in packet‐oriented systems, where rapid and stable acquisition of the major transmission parameters is essential for subsequent processing stages. On the other hand, feedback algorithms are typically used to track small deviations from the stable equilibrium point. In the current paper, we propose a new approach for blind feedforward and feedback recovery of the symbol timing, which needs just one or two samples per symbol. The method is characterized by a second filter operated in parallel to the receiver‐matched filter. Under Nyquist conditions, exemplified by baseband pulses having a square‐root raised cosine spectrum, this filter exhibits an impulse response satisfying the extended zero‐crossing property, that is, it vanishes for all integer multiples of the symbol period including the origin. Using this idea for symbol‐timing recovery, it is shown that the annoying jitter floor – typical for most timing recovery schemes and caused by inter‐symbol interference – can be avoided irrespective of the selected modulation scheme. Copyright © 2015 John Wiley & Sons, Ltd.
The role of social capital in endangered species management: A valuable resource
Authors: Ragland Chara J. , Bernacchi Leigh A. , Peterson Tarla Rai 
Published: November 2015

ABSTRACTThe whooping crane (Grus americana) is an endangered North American species facing multiple environmental and anthropogenic threats. Even if the species thrives, it must continue to be managed after recovery because the threats will not abate. We examined how social capital serves as a resource for potential community involvement in whooping crane management by conducting semi‐structured interviews (Jul–Sep 2010) of 35 individuals, 25 of whom are concerned community members who work and/or live in the wintering grounds of the lone wild population of whooping cranes in the Texas Coastal Bend, USA. We used an iterative process of inductive analysis to examine structural and cognitive dimensions of social capital within the community. We observed networks with bonding ties within the community that are strengthened by active engagement in crane‐related activities, shared values and community identity, and institutions that have fostered leadership and service. Bridging ties between community and state, federal, academic, and nonprofit organizations offer opportunities for knowledge sharing and legitimacy. Reciprocity and trust were evident from descriptions of the community working together effectively to address environmental and crane‐related concerns. Challenges to successful community involvement include finding ways for meaningful community contributions to foster greater trust between the community and federal natural resource managers. We suggest social capital in this community provides a resource that has the potential to save time and money in addressing ongoing efforts to protect this charismatic endangered species. © 2015 The Wildlife Society.
Exotic grass alters micro‐climate and mobility for northern bobwhite chicks
Authors: Martin James A. , Burkhart Jason K. , Thackston Reggie E. , Carroll John P. 
Published: November 2015

ABSTRACTConservation practices are designed to provide habitat conditions that meet the environmental requirements for species of conservation concern. However, exotic invasive grass species may reduce the efficacy of these practices because they disrupt biological processes. During 7 August–6 September 2001, we investigated 2 possible ecological impacts of bermudagrass (Cynodon dactylon) on northern bobwhite (Colinus virginianus) brood ecology in managed field margins (Laurens County, GA, USA)—reduction in mobility and increased thermal risk. We tested and compared movement rates using imprinted chicks as assays and the thermal environment using in situ temperature probes for bermudagrass and forb habitats. Furthermore, we built upon the existing thermal ecology of northern bobwhite literature and established thermal models to derive time‐to‐death values from our empirical data. Bermudagrass reduced movement times for chicks 5‐days old (0.45 min slower in treatments with bermudagrass), but not for chicks 10‐days old. Furthermore, temperatures reached higher daytime temperatures in bermudagrass plots (44.0° C vs. 40.1° C) and crossed the critical hyperthermia threshold more often (32% vs. 11%) than in forb‐dominated habitats. Based on simulations, chicks would reach thermal death much earlier in bermudagrass regardless of age. Collectively, our results suggest that bermudagrass reduces habitat quality for bobwhites through reduced movement efficiency and increased thermal stress. Large‐scale reductions in bermudagrass are unlikely because of its invasive nature and economic importance to agriculture. However, targeted control or suppression of bermudagrass prior to and following field fallowing is necessary to achieve the objectives of conservation programs for bobwhites and likely other ground‐dwelling birds. © 2015 The Wildlife Society.
Characterizing wolf–human conflicts in Wisconsin, USA
Authors: Olson Erik R. , Van Deelen Timothy R. , Wydeven Adrian P. , Ventura Stephen J. , Macfarland David M. 
Published: November 2015

ABSTRACTManagement of human–wildlife conflict is a critical component of wildlife conservation globally, especially for large carnivores. Understanding general patterns of conflict can guide management decisions, such as whether or not to consider lethal or nonlethal controls. We used wolf–human conflicts in Wisconsin, USA (1999–2011), to analyze the 4 main classes of conflict typically associated with large carnivores. Of 1,662 reported wolf (Canis lupus) incidents, 801 incidents were verified as wolf. Incidents varied seasonally, with animal husbandry practices and wolf energy demands, and increased over time in absolute numbers. Human safety concerns and nonhunting dog complaints were classified as residential‐, wildland‐, or farm‐associated. Human presence or intervention reduced the likelihood of dog mortality (vs. injury) following a wolf attack. Some wolf packs were primarily implicated in either hunting or nonhunting dog conflicts, with nonhunting dog attacks for the most part being attributable to lone or dispersing wolves. No complaints about aggressive behavior or wolf attacks on humans were investigated during the study period; however, wolves did approach humans at close range (median = 12.5 m) and attacked pets near homes. Wolf–human conflicts cluster spatially, which could be a way to prioritize mitigation efforts. To guide management decisions, managers should determine 1) what behaviors characterize habituated wolves; 2) what characteristics of wolf–human conflict determine whether or not human safety concerns should be considered; and 3) under what conditions should lethal control be implemented. Continued detailed reporting by investigators of wildlife complaints, especially behavioral data on wildlife, domestic animal(s), and complainant, will inform management decisions and facilitate assessment of prior decisions. © 2015 The Wildlife Society.
Molekulare Grundlagen der autosomal-rezessiven primären Mikrozephalie
Authors: Yigit Gökhan , Rosin Nadine , Wollnik Bernd 
Published: November 2015

ZusammenfassungDie primäre autosomal-rezessive Mikrozephalie (MCPH) ist eine genetisch sehr heterogene Erkrankung, die klinisch definiert wird durch das Vorliegen einer kongenitalen, nicht progressiven Mikrozephalie, einer mentalen Retardierung variablen Ausmaßes bei weitgehend normaler Körpergröße und das Fehlen von zusätzlichen Fehlbildungen und weiteren neurologischen Befunden. Bislang konnten Mutationen in 14 verschiedenen Genen identifiziert werden, deren Produkte auf zellulärer Ebene insbesondere bei Vorgängen der Zellteilung, der Zellzyklusregulierung und bei der Aktivierung von DNA-Reparaturmechanismen nach DNA-Schädigungen eine wichtige Rolle spielen. Darüber hinaus sind auch syndromale Formen der Mikrozephalie bekannt, zu denen u. a. das Seckel-Syndrom sowie der mikrozephale osteodysplastische primordiale Kleinwuchs Typ II (MOPD II) zählen.
Encoding of sound envelope transients in the auditory cortex of juvenile rats and adult rats
Authors: Lu Qi , Jiang Cuiping , Zhang Jiping 
Published: November 2015

AbstractAccurate neural processing of time‐varying sound amplitude and spectral information is vital for species‐specific communication. During postnatal development, cortical processing of sound frequency undergoes progressive refinement; however, it is not clear whether cortical processing of sound envelope transients also undergoes age‐related changes. We determined the dependence of neural response strength and first‐spike latency on sound rise–fall time across sound levels in the primary auditory cortex (A1) of juvenile (P20–P30) rats and adult (8–10 weeks) rats. A1 neurons were categorized as “all‐pass”, “short‐pass”, or “mixed” (“all‐pass” at high sound levels to “short‐pass” at lower sound levels) based on the normalized response strength vs. rise–fall time functions across sound levels. The proportions of A1 neurons within each of the three categories in juvenile rats were similar to that in adult rats. In general, with increasing rise–fall time, the average response strength decreased and the average first‐spike latency increased in A1 neurons of both groups. At a given sound level and rise–fall time, the average normalized neural response strength did not differ significantly between the two age groups. However, the A1 neurons in juvenile rats showed greater absolute response strength, longer first‐spike latency compared to those in adult rats. In addition, at a constant sound level, the average first‐spike latency of juvenile A1 neurons was more sensitive to changes in rise–fall time. Our results demonstrate the dependence of the responses of rat A1 neurons on sound rise–fall time, and suggest that the response latency exhibit some age‐related changes in cortical representation of sound envelope rise time.
Hands-on defibrillation and electrocardiogram artefact filtering technology increases chest compression fraction and decreases peri-shock pause duration in a simulation model of cardiac arrest
Authors: Fernando Shannon M. , Cheskes Sheldon , Howes Daniel 
Published: November 2015

AbstractBackgroundReducing pauses during cardiopulmonary resuscitation (CPR) compressions result in better outcomes in cardiac arrest. Artefact filtering technology (AFT) gives rescuers the opportunity to visualize the underlying electrocardiogram (ECG) rhythm during chest compressions, and reduces the pauses that occur before and after delivering a shock. We conducted a simulation study to measure the reduction of peri-shock pause and impact on chest compression fraction (CCF) through AFT.MethodsIn a simulator setting, participants were given a standardized cardiac arrest scenario and were randomly assigned to perform CPR/defibrillation using the protocol from one of three experimental arms: 1) Standard of Care (pauses for rhythm analysis and shock delivery); 2) AFT (no pauses for rhythm analysis, but a pause for defibrillation); or 3) AFT with hands-on defibrillation (no pauses for rhythm analysis or defibrillation). The primary outcomes were CCF and peri-shock pause duration, with secondary outcomes of pre- and post-shock pause duration.ResultsAFT with hands-on defibrillation was found to have the highest CCF (86.4%), as compared to AFT alone (83.8%, p<0.001), and both groups significantly improved CCF in comparison with the Standard of Care (76.7%, p<0.001). AFT with hands-on defibrillation was associated with a reduced peri-shock pause (2.6 seconds) as compared to AFT alone (5.3 seconds, p<0.001), and the Standard of Care (7.4 seconds, p<0.001).ConclusionsIn this cardiac arrest model, AFT results in a greater CCF by reducing peri-shock pause duration. There is also a small but detectable improvement in CCF with the addition of hands-on defibrillation.