bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensory distribution of the lateral femoral cutaneous nerve block – a randomised, blinded trial
Authors: Nersesjan M. , Hägi‐Pedersen D. , Andersen J. H. , Mathiesen O. , Dahl J. B. , Broeng L. , Thybo K. H. 
Published: February 2018

BackgroundThe lateral femoral cutaneous nerve (LFCN) block may be used for post‐operative pain management in patients undergoing total hip arthroplasty. The aim of this trial was to investigate the sensory coverage of the posterior and the lateral incision lines and the involvement of the femoral nerve after an LFCN block.MethodsThe study was a randomised, blinded trial in 20 healthy volunteers. All subjects received a bilateral LFCN block randomised to 8 ml ropivacaine on the right side and 8 ml isotonic saline on the left side, or vice versa. An orthopaedic surgeon depicted the incision lines (invisible to the investigators) prior to block performance. The distribution of the blocked area and the coverage of the incision lines were assessed with temperature discrimination and pinprick test before unblinding the incision lines. Pain during tonic heat stimulation and involvement of the femoral nerve by measuring quadriceps strength were assessed.ResultsThe mean difference in block coverage of the posterior (primary outcome) and the lateral incision lines tested with temperature discrimination were 5.8% (95% CI: −2.2 to 14.0%, P = 0.146) and 18.9% (95% CI: 6.5–31.4%, P = 0.005), respectively, comparing the active with the placebo side. A varying anatomic distribution area was observed. No clinically significant differences for experimental pain and quadriceps muscle strength were found. The block failure rate was 15%.ConclusionAn LFCN block consisting of 8 ml 0.75% ropivacaine had limited coverage of the posterior and lateral incision lines.
Medical marijuana laws and adolescent marijuana use in the United States: a systematic review and meta‐analysis
Authors: Sarvet Aaron L. , Wall Melanie M. , Fink David S. , Greene Emily , Le Aline , Boustead Anne E. , Pacula Rosalie Liccardo , Keyes Katherine M. , Cerdá Magdalena , Galea Sandro , Hasin Deborah S. 
Published: February 2018

AbstractAimsTo conduct a systematic review and meta‐analysis of studies in order to estimate the effect of US medical marijuana laws (MMLs) on past‐month marijuana use prevalence among adolescents.MethodsA total of 2999 papers from 17 literature sources were screened systematically. Eleven studies, developed from four ongoing large national surveys, were meta‐analyzed. Estimates of MML effects on any past‐month marijuana use prevalence from included studies were obtained from comparisons of pre–post MML changes in MML states to changes in non‐MML states over comparable time‐periods. These estimates were standardized and entered into a meta‐analysis model with fixed‐effects for each study. Heterogeneity among the study estimates by national data survey was tested with an omnibus F‐test. Estimates of effects on additional marijuana outcomes, of MML provisions (e.g. dispensaries) and among demographic subgroups were abstracted and summarized. Key methodological and modeling characteristics were also described. Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines were followed.ResultsNone of the 11 studies found significant estimates of pre–post MML changes compared with contemporaneous changes in non‐MML states for marijuana use prevalence among adolescents. The meta‐analysis yielded a non‐significant pooled estimate (standardized mean difference) of −0.003 (95% confidence interval = −0.012, +0.007). Four studies compared MML with non‐MML states on pre‐MML differences and all found higher rates of past‐month marijuana use in MML states pre‐MML passage. Additional tests of specific MML provisions, of MML effects on additional marijuana outcomes and among subgroups generally yielded non‐significant results, although limited heterogeneity may warrant further study.ConclusionsSynthesis of the current evidence does not support the hypothesis that US medical marijuana laws (MMLs) until 2014 have led to increases in adolescent marijuana use prevalence. Limited heterogeneity exists among estimates of effects of MMLs on other patterns of marijuana use, of effects within particular population subgroups and of effects of specific MML provisions.
Associations of postoperative mortality with the time of day, week and year
Authors: Kork F. , Spies C. , Conrad T. , Weiss B. , Roenneberg T. , Wernecke K.‐D. , Balzer F. 
Published: February 2018

SummaryStudies that have investigated circadian, weekday and seasonal variation in postoperative mortality have been relatively small or have been for scheduled surgery. We retrospectively tested a large mixed surgical cohort from a German tertiary care university hospital for the presence of cyclical variation in all‐cause in‐hospital mortality after operations performed between 2006 and 2013. We analysed mortality rates after 247,475 operations, adjusted for age, sex, comorbidities, location, urgency and duration of the surgery, and intra‐operative blood transfusions. The mortality odds ratio (95%CI) after operations started in the morning (08:00–11:00) were lowest, 0.73 (0.66–0.80), p < 0.001 and highest for operations started in the afternoon (13:00–17:00), 1.29 (1.18–1.40), p < 0.001. Mortality at the weekend was the same as during the week. There was no seasonal variation in mortality, p = 0.12. However, the interference of four‐yearly and ten‐monthly cycle amplitudes resulted in higher mortality odds ratio (95%CI) in winter 2008–2009, 1.41 (1.18–1.69), p < 0.001, and lower mortality in spring 2011 and 2012, 0.70 (0.56–0.85) and 0.67 (0.53–0.85), p < 0.001 and p = 0.001, respectively. The ability to predict cyclical phenomena would facilitate the design of interventional studies, aimed at reducing mortality following surgery in the afternoon and when cycles interfere constructively.
High‐quality human and rat spermatozoal RNA isolation for functional genomic studies
Authors: Bianchi E. , Stermer A. , Boekelheide K. , Sigman M. , Hall S. J. , Reyes G. , Dere E. , Hwang K. 
Published: February 2018

SummarySperm RNA is a sensitive monitoring endpoint for male reproductive toxicants, and a potential biomarker to assess male infertility and sperm quality. However, isolation of sperm RNA is a challenging procedure due to the heterogeneous population of cells present in the ejaculate, the low yield of RNA per spermatozoon, and the absence of 18S and 28S ribosomal RNA subunits. The unique biology of spermatozoa has created some uncertainty in the field about RNA isolation methods, indicating the need for rigorous quality control checks to ensure reproducibility of data generated from sperm RNA. Therefore, we developed a reliable and effective protocol for RNA isolation from rat and human spermatozoa that delivers highly purified and intact RNA, verified using RNA‐specific electrophoretic chips and molecular biology approaches such as RT‐PCR and Western blot analysis. The sperm RNA isolation technique was optimized using rat spermatozoa and then adapted to human spermatozoa. Three steps in the sperm isolation procedure, epididymal fluid collection, sperm purification, and spermatozoon RNA extraction, were evaluated and assessed. The sperm RNA extraction methodology consists of collection of rat epididymal fluid with repeated needle punctures of the epididymis, somatic cell elimination using detergent‐based somatic cell lysis buffer (SCLB) and the use of RNA isolation Kit. Rat sperm heads are more resistant to disruption than human spermatozoa, necessitating the addition of mechanical lysis with microbeads and heat in the rat protocol, whereas the human sperm protocol only required lysis buffer. In conclusion, this methodology results in reliable and consistent isolation of high‐quality sperm RNA. Using this technique will aid in translation of data collected from animal models, and reproducibility of clinical assessment of male factor fertility using RNA molecular biomarkers.
Early and middle Holocene ecosystem changes at the Western Carpathian/Pannonian border driven by climate and Neolithic impact
Authors: Šolcová Anna , Petr Libor , Hájková Petra , Petřík Jan , Tóth Peter , Rohovec Jan , BáTORA JOZEF , Horsák Michal 
Published: February 2018

Travertine deposits are unique archives for multidisciplinary studies of past climate changes, associated vegetation development and the evolution of human societies. Despite their high potential in palaeoecological and palaeoclimate reconstructions, investigations of travertines are rather scarce in central Europe and particularly in Slovakia. Therefore, this study focused on a travertine deposit situated on the border between the Pannonian Basin and the Western Carpathians in a small valley in Santovka village (SW Slovakia), which is unique due to the presence of archaeological artefacts with known radiocarbon ages in the palaeoecological profile. Using a multidisciplinary approach combining macrofossil, pollen, mollusc, lithological and geochemical analyses, this study investigated climate–human–vegetation interactions. The Holocene onset was marked by the early arrival of oak trees; however, forest‐steppe with a high representation of pine predominated until 9880 cal. a BP, followed by an expansion of temperate trees. The local ecosystem changed around 8600 cal. a BP when the valley was probably dammed by a travertine accumulation, probably resulting in the existence of a small travertine lake. This was associated with wetter climatic conditions, which were also documented in other sites in the Western Carpathians at that time. Surrounding temperate forest possibly retained a certain degree of openness, or local steppe habitat may have persisted on adjacent loess terraces until the neolithization of the area. Archaeological evidence represented by a ceramic shard dated to 7339 cal. a BP suggests the first appearance of humans at the site, yet pollen analysis records a significant change in vegetation first at 6650 cal. a BP. The local ecosystem records an abrupt change linked with human settlement earlier, at c. 7000 cal. a BP. Deforestation activities of the Neolithics resulted in the formation of an open calcareous fen occupied by numerous light‐demanding mollusc species. The present study provides new important data about the spread of temperate trees at the onset of the Holocene, about further vegetation changes caused by activities of the first Neolithic farmers and about climate changes in the region of southwestern Slovakia.
Comparing forest structure and biodiversity on private and public land: secondary tropical dry forests in Costa Rica
Authors: McClellan Moana , Montgomery Rebecca , Nelson Kristen , Becknell Justin 
Published: February 2018

AbstractSecondary forests constitute a substantial proportion of tropical forestlands. These forests occur on both public and private lands and different underlying environmental variables and management regimes may affect post‐abandonment successional processes and resultant forest structure and biodiversity. We examined whether differences in ownership led to differences in forest structure, tree diversity, and tree species composition across a gradient of soil fertility and forest age. We collected soil samples and surveyed all trees in 82 public and 66 private 0.1‐ha forest plots arrayed across forest age and soil gradients in Guanacaste, Costa Rica. We found that soil fertility appeared to drive the spatial structure of public vs. private ownership; public conservation lands appeared to be non‐randomly located on areas of lower soil fertility. On private lands, areas of crops/pasture appeared to be non‐randomly located on higher soil fertility areas while forests occupied areas of lower soil fertility. We found that forest structure and tree species diversity did not differ significantly between public and private ownership. However, public and private forests differed in tree species composition: 11 percent were more prevalent in public forest and 7 percent were more prevalent in private forest.Swietenia macrophylla,Cedrela odorata,andAstronium graveolenswere more prevalent in public forests likely because public forests provide stronger protection for these highly prized timber species.Guazuma ulmifoliawas the most abundant tree in private forests likely because this species is widely consumed and dispersed by cattle. Furthermore, some compositional differences appear to result from soil fertility differences due to non‐random placement of public and private land holdings with respect to soil fertility. Land ownership creates a distinctive species composition signature that is likely the result of differences in soil fertility and management between the ownership types. Both biophysical and social variables should be considered to advance understanding of tropical secondary forest structure and biodiversity.
A theory on the role of wholesalers in international trade based on economies of scope
Authors: Akerman Anders 
Published: February 2018

AbstractThis paper offers a theoretical foundation for the existence of wholesalers and other intermediaries in international trade and analyzes their role in an economy with heterogeneous manufacturing firms and fixed costs of exporting. Wholesalers are assumed to possess a technology such that they can buy manufacturing goods domestically and sell in foreign markets and they can, unlike manufacturers, export more than one good. A wholesaler therefore faces an additional fixed cost, which increases in the number of goods it handles. The presence of wholesale firms leads to productivity sorting. The most productive firms export on their own by paying a fixed cost, but a range of firms with intermediate productivity levels export through international wholesalers. A higher fixed cost of exporting to a destination means that wholesalers handle: (i) a higher share of total export volumes to this destination and (ii) a higher share of the exported product scope (i.e., the number of exported products) to this destination. A higher fixed cost of exporting gives wholesalers a larger role, since these can spread the fixed cost across more than one good. The wholesale technology therefore exhibits economies of scope. An empirical analysis using Swedish firm‐level data supports the main assumption and predictions of the model.
Epicrestal and subcrestal placement of platform‐switched implants: 18 month‐result of a randomized, controlled, split‐mouth, prospective clinical trial
Authors: Froum Stuart J. , Cho Sang‐Choon , Suzuki Takanori , Yu Paul , Corby Patricia , Khouly Ismael 
Published: February 2018

AbstractObjectivesTo evaluate the changes in marginal bone levels (MBL) and soft tissue dimension around platform‐switched implants with the implant–abutment junction (IAJ) placed at the crest or 1.5–2 mm subcrestally.Materials and methodsIn all, 96 platform‐switched implants were placed in either the posterior maxilla or mandible in 48 partially edentulous patients in a split‐mouth study. All implants were provisionally restored after 4–5 months and definitively after 6 months (T6). Radiographic assessment of MBL was assessed at implant placement (T0), T6, 12 months (T12), and 18 months (T18) after placement. Mid‐buccal soft tissue and papilla measurements were performed at T6, T12, and T18.ResultsIn all, 43 patients with 86 implants completed the study. The T18 examination showed an implant survival rate of 100% in both groups. Analysis showed that MBL varied as a function of IAJ location, which indicated more coronal bone levels with subcrestal (2.39 ± 0.08 mm) than with epicrestal placements (0.88 ± 0.08 mm) (p < .05). Greater average marginal bone loss was found in the subcrestal group (0.40 ± 0.07 mm) compared to the epicrestal group (0.13 ± 0.08 mm) although no statistically significant difference was found at T18 (p > .05). Levels of mid‐buccal soft tissue had no significant changes over time, regardless of group (p > .05). There was a significant difference in increase in papilla between T6 and T12 and T18 (p = .005 and .001), but not between T12 and T18 (p = .61). These papilla levels and changes were similar between groups (p > .05).ConclusionsThe MBL changes around platform‐switched implants with same geometry were not affected by the epicrestal or subcrestal location of the IAJ. Furthermore, the location of the IAJ did not affect the implant survival and soft tissue dimensions. However, no bone loss was located apical to the IAJ when the implants were placed subcrestally.
Cost shifting and other perverse incentives in biodiversity offsetting in India
Authors: Narain Divya , Maron Martine 
Published: February 2018

AbstractBiodiversity offsetting aims to compensate for development‐induced biodiversity loss through commensurate conservation gains and is gaining traction among governments and businesses. However, cost shifting (i.e., diversion of offset funds to other conservation programs) and other perverse incentives can undermine the effectiveness of biodiversity offsetting. Additionality—the requirement that biodiversity offsets result in conservation outcomes that would not have been achieved otherwise—is fundamental to biodiversity offsetting. Cost shifting and violation of additionality can go hand in hand. India's national offsetting program is a case in point. Recent legislation allows the diversion of offset funds to meet the country's preexisting commitments under the United Nations Framework Convention on Climate Change (UNFCCC) and United Nations Convention on Biological Diversity (CBD). With such diversions, no additional conservation takes place and development impacts remain uncompensated. Temporary additionality cannot be conceded in light of paucity of funds for preexisting commitments unless there is open acknowledgement that fulfillment of such commitments is contingent on offset funds. Two other examples of perverse incentives related to offsetting in India are the touting of inherently neutral offsetting outcomes as conservation gains, a tactic that breeds false complacency and results in reduced incentive for additional conservation efforts, and the clearing of native vegetation for commercial plantations in the name of compensatory afforestation, a practice that leads to biodiversity decline. The risks accompanying cost shifting and other perverse incentives, if not preempted and addressed, will result in net loss of forest cover in India. We recommend accurate baselines, transparent accounting, and open reporting of offset outcomes to ensure biodiversity offsetting achieves adequate and additional compensation for impacts of development.
Asthma among adult patients presenting with dyspnea to the emergency department: An observational study
Authors: Kuan Win Sen , Craig Simon , Kelly Anne‐Maree , Keijzers Gerben , Klim Sharon , Graham Colin A , Jones Peter , Holdgate Anna , Lawoko Charles , Laribi Said 
Published: February 2018

AbstractIntroductionShortness of breath is a common presenting symptom to the emergency department (ED) that can arise from a myriad of possible diagnoses. Asthma is one of the major causes.ObjectiveThe aim of this study was to describe the demographic features, clinical characteristics, management and outcomes of adults with an ED diagnosis of asthma who presented to an ED in the Asia Pacific region with a principal symptom of dyspnea.MethodsPlanned sub‐study of patients with an ED diagnosis of asthma identified in the Asia, Australia and New Zealand Dyspnoea in Emergency Departments (AANZDEM) study. AANZDEM was a prospective cohort study conducted in 46 EDs in Australia, New Zealand, Singapore, Hong Kong and Malaysia over three 72 hour periods in May, August and October 2014. Primary outcomes were patient epidemiology, clinical features, treatment and outcomes (hospital length of stay (LOS) and mortality).ResultsOf the 3044 patients with dyspnea, 387 (12.7%) patients had an ED diagnosis of asthma. The median age was 45 years, 60.1% were female, 16.1% were active or recent smokers and 30.4% arrived by ambulance. Inhaled bronchodilator therapy was initiated in 88.1% of patients, and 66.9% received both inhaled bronchodilators and systemic corticosteroids. After treatment in the ED, 65.4% were discharged. No death was reported.ConclusionAsthma is common among patients presenting with a principal symptom of dyspnea in the ED of the Asia Pacific region. There was a suboptimal adherence to international guidelines on investigations and treatments of acute asthma exacerbations presenting an opportunity to improve the efficiency of care.
Reference values for respiratory impedance measured by the forced oscillation technique in adult men and women
Authors: Ribeiro Fernando Carlos Vetromille , Lopes Agnaldo José , Melo Pedro Lopes de 
Published: February 2018

AbstractIntroductionThe forced oscillation technique (FOT) is a particularly useful test of the mechanical properties of the respiratory system that has an increasingly important role in lung function laboratories. There is general agreement in the literature that the determination of reference values is of utmost importance in the clinical use of the FOT.ObjectiveOur aim was to present reference values for whole‐breath FOT measurements, establish which anthropometric variables were more predictive of impedance parameters, and provide all the details to adequately adopt these reference equations in individual laboratories.MethodsWe prospectively evaluated a randomly selected non‐smoking sample of the adult Brazilian population (288 subjects, 144 males and 144 females aged 20‐86 years). The volunteers were separated by sex and divided into six groups based on decade of age. Sex‐specific linear prediction equations were developed by multiple regression analysis using age, body mass and height as explanatory variables.ResultsAge introduced a slight, but significant, reduction of resistance in men (P < .001) and women (P < .001). In general, significantly higher values of resistance were observed in females (P < .0001). Among the anthropometric variables analyzed, height was the best predictor for all parameters studied.ConclusionThis study provides an original frame of reference for the FOT in Brazilian males and females aged 20‐86 years. Height was the best predictor of respiratory impedance parameters. Details contributing to an adequate adoption of these reference equations elsewhere by transference and verification are also provided.