bluuebunny/crossref_metadata_2025 huggingface dataset:
The bright side and dark side of group heterogeneity within online brand community
Authors: Liao Junyun , Yang Defeng , Wei Haiying , Guo Yulang
Published: July 2019

Purpose

Despite the increasingly common view that online brand community (OBC) members are heterogeneous, knowledge concerning the impact of group heterogeneity on community and brand level outcomes is lacking. In response and drawing from organization research, this paper aims to study the consequences of two types of group heterogeneity (i.e. visible heterogeneity and value heterogeneity) on brand community commitment and brand commitment. The moderating role of tenure in a community is also examined.

Design/methodology/approach

A survey of 467 members of OBCs was conducted, and structural equation modeling was used to test hypotheses.

Findings

The results show that perceived visible heterogeneity positively affects brand community commitment, whereas perceived value heterogeneity has a negative effect on it. Brand community commitment positively relates to brand commitment; it also mediates the effect of perceived visible heterogeneity and perceived value heterogeneity on brand commitment. Further, the positive effect of visible heterogeneity on brand community commitment is stronger for short-tenure members, but the negative effect of value heterogeneity is stronger for long-tenure members.

Practical implications

The findings suggest that managers should make efforts to foster visible heterogeneity and reduce value heterogeneity. In addition, managers are advised to emphasize the characteristics that carry different appeal for members of different tenure.

Originality/value

This research is one of the first few quantitative studies to examine the influence of brand community heterogeneity on community, and especially brand level outcomes. It extends the literature on the effect of brand community on brands and adds to the emerging heterogeneity view of OBCs.
Evaluation of community-based psychological first aid in oncology
Authors: Gray Brandon L. , Gaster Samuel , Early Christina , Reed Amanda
Published: July 2019

Purpose

Healthcare professionals work in high stress environments and may benefit from organizational efforts that enhance coping abilities. Community-based psychological first aid (CBPFA) is an evidence-informed program designed for building these skills and promoting resilience during stressful times. However, few studies have examined the effectiveness of CBPFA. The paper aims to discuss these issues.

Design/methodology/approach

This study examined the effectiveness of CBPFA training in promoting occupational self-efficacy and intentions to use CBPFA among oncology care staff over time using a longitudinal design.

Findings

Participants reported increased occupational self-efficacy and intentions to use CBPFA skills after completing training. These factors remained stable at one-month follow-up.

Research limitations/implications

The implications of these results are limited by the lack of a control group in the study’s design, relatively homogenous sample and participant dropout.

Originality/value

Despite the study’s limitations, these results represent an initial step in empirically examining the impact of CBPFA trainings and providing evidence that CBPFA may be an effective preparedness and development program in high-stress healthcare settings.
Performance of gas nanosensor in 1-4 per cent hydrogen concentration
Authors: Behzadi Pour Ghobad , Fekri Aval Leila , Esmaili Parisa
Published: July 2019

Purpose

This study aims to investigate the fabrication of hydrogen gas sensor based on metal–oxide–semiconductor (MOS) microstructure. The palladium nanoparticles (PdNPs) as gate metal have been deposited on the oxide film using spin coating.

Design/methodology/approach

The PdNPs and the surface of oxide film were analyzed using Transmission electron microscopy. The capacitance-voltage (C-V) curves for the MOS sensor in 1, 2 and 4 per cent hydrogen concentration and in 100 KHz frequency at the room temperature were reported.

Findings

The response times for 1, 2 and 4 per cent hydrogen concentration were 2.5 s, 1.5 s and 1 s, respectively. The responses (R per cent) of MOS sensor to 1, 2 and 4 per cent hydrogen concentration were 42.8, 47.3 and 52.6 per cent, respectively.

Originality/value

The experimental results demonstrate that the MOS hydrogen gas sensor based on the PdNPs gate, shows the fast response and recovery compared to other hydrogen gas sensors based on the Pd.
Platycodin D inhibits proliferation, migration and induces chemosensitization through inactivation of the NF‐κB and JAK2/STAT3 pathways in multiple myeloma cells
Authors: Wu Di , Zhang Wei , Chen Ying , Ma Hong , Wang Mengchang
Published: July 2019

Multiple myeloma (MM) is a malignancy characterized by the proliferation of malignant plasma cells. Platycodin D (PLD) is a triterpenoid saponin that exerts anti‐tumour activity through multiple mechanisms. However, the role of PLD in MM remains unknown. Here, we investigated the effect of PLD on MM cell lines NCI‐H929 and U266B1, and elucidated the underlying molecular mechanism. Cell Counting Kit‐8 assay showed that the proliferation of NCI‐H929 and U266B1 cells was significantly decreased after PLD treatment. Transwell assay confirmed that PLD treatment suppressed migration of NCI‐H929 and U266B1 cells. Flow cytometry results indicated that the apoptotic rates of bortezomib (BTZ)‐treated NCI‐H929 and U266B1 cells were markedly increased after PLD treatment. Western blot analysis revealed that bcl‐2 expression was decreased, while bax expression was increased in PLD‐treated NCI‐H929 and U266B1 cells compared with that in BTZ‐treated cells. Furthermore, PLD treatment blocked the activation of nuclear factor‐kappa B (NF‐κB) and Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signalling pathways in NCI‐H929 cells. Taken together, these data showed that PLD inhibited proliferation and migration, and enhanced chemosensitization to BTZ through inactivation of the NF‐κB and JAK2/STAT3 pathways in MM cell lines. These findings indicated that PLD might serve as a novel therapeutic agent for the treatment of MM.
Special clinical characteristics and outcomes in Chinese pediatric patients with early‐onset Crohn's disease
Authors: Tang Wen Juan , Shi Peng , Zheng Cui Fang , Shi Jie Ru , Qiu Xiao Xia , Wang Sheng Nan , Huang Ying
Published: July 2019

Objective

To study the clinical and nutritional characteristics of early‐onset Crohn's disease (EO‐CD) in China.

Methods

Patients were defined as having EO‐CD (age at diagnosis <10 y) or late‐onset Crohn's disease (LO‐CD; age at diagnosis of 10‐17 y). Their characteristics, clinical, and nutritional data were collected at baseline and at each follow‐up visit. Statistical analyses were used to compare differences in both groups.

Results

From July 1993 to February 2017, of the 137 children enrolled, 68 (49.6%) had EO‐CD and 69 (50.4%) had LO‐CD. More patients with EO‐CD than those with LO‐CD presented with diarrhea, hematochezia, growth delay, anemia and skin disease, and had higher pediatric Crohn's disease activity index scores at diagnosis (all P < 0.05). Fewer patients with EO‐CD achieved their first remission (42.6% vs 76.8%, P < 0.0001) during follow‐up. Patients with EO‐CD required a longer treatment time to reach remission (P = 0.0049) and had a higher mortality rate (P = 0.0133), as well as lower height and weight percentiles (P = 0.0200 and 0.0288, respectively), hemoglobin (P = 0.0185) and albumin levels (P = 0.0002), zinc (P = 0.0024) and iron (P = 0.0110) concentrations in blood at diagnosis.

Conclusion

The EO‐CD group had worse clinical outcomes and nutritional status than the LO‐CD group.
Association of IRF5 rs2004640 polymorphism and systemic lupus erythematosus: A meta‐analysis
Authors: Wang Jia‐Min , Huang An‐Fang , Yuan Zhi‐Chao , Su Lin‐Chong , Xu Wang‐Dong
Published: July 2019

Background

This study aimed to discuss the relationship between interferon regulatory factor (IRF)5 gene rs2004640 T/G polymorphism and systemic lupus erythematosus (SLE) susceptibility.

Methods

A meta‐analysis was calculated on the association between rs2004640 polymorphism and SLE by allelic contrast (T vs G), additive model (TT vs GG), recessive model (TT vs TG + GG) and dominant model (TT + TG vs GG).

Results

A total of 28 comparisons were identified, including 11 228 SLE cases and 14 374 controls. Meta‐analysis revealed a significant association between allele T and SLE in overall populations (odds ratio [OR] = 1.393, 95% CI: 1.276‐1.522, P < 0.001). Stratification by ethnicity indicated strong associations between T allele and SLE in Asians, Europeans and Latin Americans (OR = 1.256, 95% CI: 1.073‐1.469, P = 0.004; OR = 1.338, 95% CI: 1.080‐1.659, P = 0.008; OR = 1.853, 95% CI: 1.488‐2.308, P < 0.001). Results also showed significant associations between the additive model and SLE in all subjects and Asians (OR = 1.999, 95% CI: 1.442‐2.771, P < 0.001; OR = 1.544, 95% CI: 1.009‐2.362, P < 0.045). In addition, we found significant associations between the dominant model and SLE in all populations and Asians (OR = 1.521, 95% CI: 1.257‐1.841, P < 0.001; OR = 1.270, 95% CI: 1.136‐1.421, P < 0.001). A marginal association was detected between the recessive mode and SLE in overall subjects (OR = 1.480, 95% CI: 1.022‐2.144, P = 0.038).

Conclusion

The current study suggested that individuals carrying rs2004640 T allele correlated with a high risk of SLE, and the IRF5 rs2004640 polymorphism was associated with SLE susceptibility.
Rag1 immunodeficiency‐induced early aging and senescence in zebrafish are dependent on chronic inflammation and oxidative stress
Authors: Novoa Beatriz , Pereiro Patricia , López‐Muñoz Azucena , Varela Mónica , Forn‐Cuní Gabriel , Anchelin Monique , Dios Sonia , Romero Alejandro , Martinez‐López Alicia , Medina‐Gali Regla María , Collado Manuel , Coll Julio , Estepa Amparo , Cayuela María Luisa , Mulero Victoriano , Figueras Antonio
Published: July 2019

In mammals, recombination activating gene 1 (RAG1) plays a crucial role in adaptive immunity, generating a vast range of immunoglobulins.Rag1−/−zebrafish (Danio rerio) are viable and reach adulthood without obvious signs of infectious disease in standard nonsterile conditions, suggesting that innate immunity could be enhanced to compensate for the lack of adaptive immunity. By using microarray analysis, we confirmed that the expression of immunity‐ and apoptosis‐related genes was increased in therag1−/−fish. This tool also allows us to notice alterations of the DNA repair and cell cycle mechanisms inrag1−/−zebrafish. Several senescence and aging markers were analyzed. In addition to the lower lifespan ofrag1−/−zebrafish compared to their wild‐type (wt) siblings,rag1−/−showed a higher incidence of cell cycle arrest and apoptosis, a greater amount of phosphorylated histone H2AX, oxidative stress and decline of the antioxidant mechanisms, an upregulated expression and activity of senescence‐related genes and senescence‐associated β‐galactosidase, respectively, diminished telomere length, and abnormal self‐renewal and repair capacities in the retina and liver. Metabolomic analysis also demonstrated clear differences between wt andrag1−/−fish, as was the deficiency of the antioxidant metabolitel‐acetylcarnitine (ALCAR) inrag1−/−fish. Therefore, Rag1 activity does not seem to be limited to V(D)J recombination but is also involved in senescence and aging. Furthermore, we confirmed the senolytic effect of ABT‐263, a known senolytic compound and, for the first time, the potential in vivo senolytic activity of the antioxidant agent ALCAR, suggesting that this metabolite is essential to avoid premature aging.
Feline hip joint anatomy in magnetic resonance images
Authors: Głodek Joanna , Milewska Kamila , Tobolska Angelika , Grabarczyk Łukasz , Maksymowicz Wojciech , Bada Isaac , Adamiak Zbigniew
Published: July 2019

The aim of this study was to develop an anatomical model of the feline hip joint for low‐field magnetic resonance imaging (LF‐MRI) based on high‐field magnetic resonance imaging (HF‐MRI). The study was performed on six adult clinically healthy European shorthair cats, aged 1–3 years, with body weight of 2.8–4.4 kg. The animals were examined with the use of the Vet‐MRI Grande Esaote LF (0.25 T) scanner and high‐field Siemens Magnetom TRIO (3 T) MRI scanner. In the LF‐MRI, most satisfactory results in T1‐weighted images were obtained when TE was 26 ms in all three planes and when TR was 350–950 ms in the transverse plane, 950–1150 ms in the sagittal plane and 520–750 ms in the dorsal plane. In T2‐weighted images, TE was 90 ms in the transverse and dorsal plane and 120 ms in the sagittal plane. The results were presented as images acquired with LF‐MRI scanners in three planes. The slice thickness was 3 mm for each plane. In LF‐MRI, muscles in the hip joint region and round ligament were well visualized. Unlike in LF‐MRI, the cross section of the femoral nerve was identified in HF‐MRI scans. In examinations of the feline hip joint, the main limitations of LF‐MRI were a lack of reliable contrast between articular cartilage and synovial fluid as well as longer scan time. Despite the above, LF‐MRI images were characterized by good contrast between bones and the surrounding soft tissues.
A novel nonsense variant in PLS3 causes X‐linked osteoporosis in a Chinese family
Authors: Wang Lianqing , Bian Xinchao , Cheng Guangying , Zhao Peiqing , Xiang Xinxin , Tian Wenxiu , Li Tao , Zhai Qiaoli
Published: July 2019

Osteoporosis is a complex bone metabolic disorder. Genetic factors play an important role in the development of osteoporosis. Mutations in more than 15 genes have been identified to be responsible for osteoporosis to date. Most recently, the gene PLS3 encoding plastin 3 was recognized to be involved in X‐linked osteoporosis. Here, we recruited a four‐generation Chinese family with X‐linked osteoporosis, which had its onset in childhood and was characterized by peripheral fractures and low bone mineral density. All affected individuals shared a nonsense variant (c.244C > T) in exon 4 of PLS3 on Xq23. The variant in affected individuals segregated with the osteoporosis phenotype. By restriction analysis using Dra I, this variant was confirmed in all affected individuals but was not detected in unaffected family members or in 100 unrelated Chinese male controls. The variant was predicted to cause a premature termination of messenger RNA (mRNA) translation (p.Gln82*). The mutant mRNA degraded via the mechanism of “nonsense‐mediated mRNA decay.” In the present study, we identified a novel nonsense variant of PLS3 in early‐onset X‐linked osteoporosis and provided a novel insight into the molecular mechanism underlying the pathogenesis of osteoporosis.
Acute Carbon Monoxide Poisoning Secondary to Cigarette Smoking in a 40‐Year‐Old Man: A Case Report
Authors: Neilsen Beth K. , Aloi Joseph , Sharma Ashish
Published: July 2019

Background and Objectives

Carbon monoxide is one of the most common causes of fatal intoxications in the United States, and multiple previous studies have demonstrated that cigarette smokers have higher levels of carbon monoxide in their blood. However, the potential negative effects due to acute carbon monoxide poisoning from excessive cigarette smoking have not been well established.

Methods

This is a single patient case report.

Results

In this case report, a 40‐year‐old male with a past medical history of depression, anxiety, panic attacks, and substance use disorder developed symptomatic, acute carbon monoxide poisoning secondary to heavy cigarette smoking in a confined space. In this patient, the cessation of clonazepam therapy coincided with increasing anxiety and panic disorder with agoraphobia triggering an escalation in his cigarette smoking. The patient smoked three packs of cigarettes in 3 hours and developed worsening of his symptoms. He required inpatient treatment with benzodiazepines and hyperbaric oxygen.

Discussion and Conclusions

Therefore, it is important to recognize cigarette smoke as a significant source of carbon monoxide exposure.

Scientific Significance

While the negative effects of cigarette smoking are often perceived as being chronic and only coming to fruition after numerous years of exposure, it is important for both physicians and patients to recognize the possibility for potentially life‐threatening acute toxicity secondary to carbon monoxide exposure. (Am J Addict 2019;28:413–415)
The quest for the human ocular accommodation mechanism
Authors: de Jong Paulus T.V.M.
Published: July 2019

We have known the accommodation phenomenon since 400 BC. Hypotheses about its mechanisms varied widely for two millennia. Early in the 17th century, when people became more aware of ophthalmic optics, Scheiner and Descartes were close to solving that accommodation worked by changes in the lens. Others rejected their idea, and people even denied the existence of accommodation because there was no clear proof. In the early 19th century, evidence accumulated for accommodation mechanisms studying bird, fish, insect, mammal and human eyes. On the discovery of muscle fibres in the ciliary body, attention shifted to its role in accommodation. Around 1850, came the proof that accommodation occurs by a change in the anterior lens curvature. Still for another 50 years, controversies remained about the exact changes in the lens and the precise accommodation mechanism. On looking back, this is not surprising because only late in the 20th century did it become clear that one cannot extrapolate from the multitude of accommodation mechanisms in the animal kingdom to human eyes.
Gastric MALT lymphoma in a population‐based study in France: clinical features, treatments and survival
Authors: Matysiak‐Budnik Tamara , Jamet Philippe , Ruskoné‐Fourmestraux Agnès , de Mascarel Antoine , Velten Michel , Maynadié Marc , Woronoff Anne‐Sophie , Trétarre Brigitte , Marrer Emilie , Delafosse Patricia , Ligier Karine , Lapôtre Ledoux Bénédicte , Daubisse Laetitia , Bouzid Laïla , Orazio Sébastien , Cowppli‐Bony Anne , Monnereau Alain
Published: July 2019

Background

Gastric mucosa‐associated lymphoid tissue (MALT) lymphoma is a rare disease, and most available data on gastric MALT lymphoma (GML) come from clinical studies of selected patients treated in centres of excellence.

Aims

To analyse the clinical features, management and survival of GML patients in a population‐based study in France

Methods

All new cases of GML diagnosed between 2002 and 2010 in 11 French areas covered by cancer registries were included. Pathology reports were verified and, if necessary, reviewed by an expert pathologist. All clinical data were retrospectively collected from medical files and analysed using stata V. 14 software.

Results

Four hundred and sixteen patients with confirmed GML (50% male, median age 67 years) were identified. Among them, 44 showed an early transformation into diffuse large B cell lymphoma and were considered to have had an initially missed high‐grade lymphoma. At diagnosis, 76% of patients were at stage IE/II, and 24% at stage III/IV of the disease. Helicobacter pylori infection was found in 57% of the patients. Eradication treatment was administered to 76% of patients and complete remission (CR) was obtained in 39%. One hundred and ninety patients received at least one other treatment, including 10 already in CR after eradication. Altogether, CR was obtained in 70% of patients and the 5‐year overall survival was 79% (95% CI [75‐83]).

Conclusions

In comparison to clinical series, in the general population, GMLs are more frequently diagnosed at an advanced stage, their clinical management is heterogeneous, and there is a risk of misdiagnosis and overtreatment. These results highlight the necessity of following currently available guidelines in this field.
NEW ANALYSIS OF CYLINDRICAL AND OVOID JARS (‘ARCHIVE JARS') FROM SOUTHERN JUDEA
Authors: Ben‐Shlomo D. , Mommsen H.
Published: July 2019

This paper presents new compositional analysis of 26 fragments of the much‐debated cylindrical and ovoid jars, a vessel type first defined at Khirbet Qumran and associated with the Dead Sea Scrolls. The new samples include 15 examples from Tel Ḥevron, a site which yielded a pottery workshop and that carries certain similarities with Khirbet Qumran during the Early Roman period, as well as several examples from Jericho and Masada. According to the new as well as previous analyses, many of these jars were produced in the Ḥevron area; another source may be located in the northern Dead Sea area. The actual function of these jars, and whether they ever contained scrolls, is still unclear.
A risk stratification for systemic immunoglobulin light‐chain amyloidosis with renal involvement
Authors: Li Ting , Huang Xianghua , Wang Qingwen , Zhao Liang , Ren Guisheng , Chen Wencui , Zheng Chunxia , Zhou Minlin , Jiang Qi , Yin Ru , Liu Zhihong
Published: July 2019

Renal involvement is found in about 70% of patients with systemic immunoglobulin light‐chain (AL) amyloidosis. However, there is no risk stratification system specialized for renal AL concerning patients’ survival. Galectin‐3 (Gal‐3) has been reported to portend poor prognosis in other renal diseases. We measured Gal‐3 and several traditional risk biomarkers of AL in baseline samples from 253 consecutive patients diagnosed with renal AL. At baseline, Gal‐3 [Hazard ratio (HR): 1·46; P = 0·033], high‐sensitivity cardiac troponin T (hs‐cTnT) (HR: 2·65; P < 0·001) and difference between involved and uninvolved free light chains (dFLC) (HR: 1·81; P = 0·001) were independent predictors of all‐cause mortality. The cut‐off points for Gal‐3, hs‐cTnT, and dFLC were 20·24 ng/ml, 0·026 ng/ml, and 75·89 mg/l, respectively. Patients were stratified into four stages by assigning a score of 1 for each of the three biomarkers above the cut‐off point. The proportions of patients with disease stages 1, 2, 3 and 4 were 17·0%, 37·2%, 29·2% and 16·6%, and the median overall survival times from diagnosis were 100, 60, 29 and 15 months, respectively (P < 0·01). Higher level of Gal‐3 is associated with increased risk for mortality, and the risk stratification based on Gal‐3 is a reliable model for predicting mortality in AL amyloidosis with renal involvement.
Ants, fire, and bark traits affect how African savanna trees recover following damage
Authors: Wigley Benjamin J. , Coetsee Corli , Kruger Laurence M. , Ratnam Jayashree , Sankaran Mahesh
Published: July 2019

Bark damage resulting from elephant feeding is common in African savanna trees with subsequent interactions with fire, insects, and other pathogens often resulting in tree mortality. Yet, surprisingly little is known about how savanna trees respond to bark damage. We addressed this by investigating how the inner bark of marula (Sclerocarya birrea), a widespread tree species favoured by elephants, recovers after bark damage. We used a long‐term fire experiment in the Kruger National Park to measure bark recovery with and without fire. At 24 months post‐damage, mean wound closure was 98, 92, and 72%, respectively, in annual and biennial burns and fire‐exclusion treatments. Fire exclusion resulted in higher rates of ant colonization of bark wounds, and such ant colonization resulted in significantly lower bark recovery. We also investigated how ten common savanna tree species respond to bark damage and tested for relationships between bark damage, bark recovery, and bark traits while accounting for phylogeny. We found phylogenetic signal in bark dry matter content, bark N and bark P, but not in bark thickness. Bark recovery and damage was highest in species which had thick moist inner bark and low wood densities (Anacardiaceae), intermediate in species which had moderate inner bark thickness and wood densities (Fabaceae) and lowest in species which had thin inner bark and high wood densities (Combretaceae). Elephants prefer species with thick, moist inner bark, traits that also appear to result in faster recovery rates.
Evaluation of the antitumor mechanism of antibody‐drug conjugates against tissue factor in stroma‐rich allograft models
Authors: Tsumura Ryo , Manabe Shino , Takashima Hiroki , Koga Yoshikatsu , Yasunaga Masahiro , Matsumura Yasuhiro
Published: July 2019

Tissue factor (TF) is known to be overexpressed in various cancers including pancreatic cancer. The upregulation of TF expression has been observed not only in tumor cells, but also in tumor stromal cells. Because of the potential of TF as a delivery target, several studies investigated the effectiveness of Ab‐drug conjugates (ADCs) against TF for cancer therapy. However, it is still unclear whether anti‐TF ADC can exert toxicity against both tumor cells and tumor stromal cells. Here, we prepared ADC using a rat anti‐mouse TF mAb (clone.1157) and 2 types of in vivo murine pancreatic cancer models, one s.c. and other orthotopic with an abundant tumor stroma. We also compared the feasibility of bis‐alkylating conjugation (bisAlk) with that of conventional maleimide‐based conjugation (MC). In the s.c. models, anti‐TF ADC showed greater antitumor effects than control ADC. The results also indicated that the bisAlk linker might be more suitable than the MC linker for cancer treatments. In the orthotopic model, anti‐TF ADC showed greater in vivo efficacy and more extended survival time control ADC. Treatment with anti‐TF ADC (20 mg/kg, three times a week) did not affect mouse body weight changes in any in vivo experiment. Furthermore, immunofluorescence staining indicated that anti‐TF ADC delivered agents not only to TF‐positive tumor cells, but also to TF‐positive tumor vascular endothelial cells and other tumor stromal cells. We conclude that anti‐TF ADC should be a selective and potent drug for pancreatic cancer therapy.
Does phenotypic plasticity initiate developmental bias?
Authors: Parsons Kevin J. , McWhinnie Kirsty , Pilakouta Natalie , Walker Lynsey
Published: July 2019

The generation of variation is paramount for the action of natural selection. Although biologists are now moving beyond the idea that random mutation provides the sole source of variation for adaptive evolution, we still assume that variation occurs randomly. In this review, we discuss an alternative view for how phenotypic plasticity, which has become well accepted as a source of phenotypic variation within evolutionary biology, can generate nonrandom variation. Although phenotypic plasticity is often defined as a property of a genotype, we argue that it needs to be considered more explicitly as a property of developmental systems involving more than the genotype. We provide examples of where plasticity could be initiating developmental bias, either through direct active responses to similar stimuli across populations or as the result of programmed variation within developmental systems. Such biased variation can echo past adaptations that reflect the evolutionary history of a lineage but can also serve to initiate evolution when environments change. Such adaptive programs can remain latent for millions of years and allow development to harbor an array of complex adaptations that can initiate new bouts of evolution. Specifically, we address how ideas such as the flexible stem hypothesis and cryptic genetic variation overlap, how modularity among traits can direct the outcomes of plasticity, and how the structure of developmental signaling pathways is limited to a few outcomes. We highlight key questions throughout and conclude by providing suggestions for future research that can address how plasticity initiates and harbors developmental bias.
Contrasting forms of competition set elevational range limits of species
Authors: Chan Shih‐Fan , Shih Wei‐Kai , Chang An‐Yu , Shen Sheng‐Feng , Chen I‐Ching
Published: July 2019

How abiotic and biotic factors constrain distribution limits at the harsh and benign edges of species ranges is hotly debated, partly because macroecological experiments testing the proximate causes of distribution limits are scarce. It has long been recognized – at least since Darwin’sOn the Origin of Species– that a harsh climate strengthens competition and thus sets species range limits. Using thorough field manipulations along a large elevation gradient, we show the mechanisms by which temperature determines competition type, resulting in a transition from interference to exploitative competition from the lower to the upper elevation limits in burying beetles (Nicrophorus nepalensis). This transition is an example of Darwin’s classic hypothesis that benign climates favor direct competition for highly accessible resources while harsh climates result in competition through resources of high rivalry. We propose that identifying the properties of these key resources will provide a more predictive framework to understand the interplay between biotic and abiotic factors in determining geographic range limits.
Keystone mutualism influences forest tree growth at a landscape scale
Authors: Clark Robert Emerson , Gutierrez Illan Javier , Comerford Mattheau S. , Singer Michael S.
Published: July 2019

Interactions between ants and phloem‐feeding herbivores are characterised as a keystone mutualism because they restructure arthropod communities and generate trophic cascades. Keystone interactions in terrestrial food webs are hypothesised to depend on herbivore community structure and bottom‐up effects on plant growth. Here, we tested this prediction at a landscape scale with a long‐term ant‐exclusion experiment on hickory saplings in the context of spatial variation in herbivore community structure and habitat quality. We quantified top‐down effects of ants, herbivore communities as well as abiotic factors impacting hickory shoot growth. We found that ants influenced shoot growth via strong, context‐dependent, compensatory effects, with clear cascading benefits only when phloem‐feeders were present and chewing herbivore abundance was high. By contrast, while several landscape variables predicted hickory growth, they did not mediate the strength of cascading effects of ants. These results suggest that ant/sap‐feeder mutualisms may regulate forest productivity by mediating effects of multiple herbivore guilds.
Addressing a real‐life problem: treatment with intravenous thrombolysis and mechanical thrombectomy in acute stroke patients with an extended time window beyond 4.5 h based on computed tomography perfusion imaging
Authors: Feil K. , Reidler P. , Kunz W. G. , Küpper C. , Heinrich J. , Laub C. , Müller K. , Vöglein J. , Liebig T. , Dieterich M. , Kellert L.
Published: July 2019

Background and purpose

Acute ischemic stroke treatment with intravenous thrombolysis (IVT) is restricted to a time window of 4.5 h after known or presumed onset. Recently, magnetic resonance imaging‐guided treatment decision‐making in wake‐up stroke (WUS) was shown to be effective. The aim of this study was to determine the safety and outcome of IVT in patients with a time window beyond 4.5 h selected by computed tomography perfusion (CTP) imaging.

Methods

We analyzed all consecutive patients last seen well beyond 4.5 h after stroke onset treated with IVT based on CTP between January 2015 and October 2018. CTP was visually assessed to estimate the mismatch between cerebral blood flow and cerebral blood volume maps. Early infarct signs were documented according to Alberta Stroke Program Early CT Score (ASPECTS). Safety data were obtained for mortality and symptomatic intracerebral hemorrhage (sICH). Follow‐up was assessed with the modified Rankin Scale (mRS).

Results

A total of 70 patients fulfilled the inclusion criteria (mean age ± SD 77.6 ± 11.5 years, 50.0% female). Median National Institutes of Health Stroke Scale score on admission was 8.0 [interquartile range (IQR), 4–14]. The most frequent reasons for an extended time window were WUS (60.0%) and delayed hospital admission (27.1%). Median time from last seen well to IVT was 11.4 h. Median ASPECTS was 10 (IQR, 9–10) and CTP mismatch 90% (IQR, 80%–100%). A total of 24 patients (34.3%) underwent additional mechanical thrombectomy. sICH occurred in four patients (5.7%). At follow‐up, 49.3% had an mRS score of 0–2 and 22.4% had an mRS score of 0–1.

Conclusions

In patients presenting in an extended time window beyond 4.5 h, IVT treatment with decision‐making based on CTP might be a safe procedure. Further evaluation in clinical trials is needed.
Adaptive limitations of white spruce populations to drought imply vulnerability to climate change in its western range
Authors: Sang Zihaohan , Sebastian‐Azcona Jaime , Hamann Andreas , Menzel Annette , Hacke Uwe
Published: July 2019

A cost‐effective climate change adaptation strategy for the forestry sector is to move seed sources to more northern and higher elevation planting sites as part of ongoing reforestation programs. This is meant to match locally adapted populations with anticipated environments, but adaptive traits do not always show population differences suitable to mitigate climate change impacts. For white spruce, drought tolerance is a critical adaptive trait to prevent mortality and productivity losses. Here, we use a 40‐year‐old provenance experiment that has been exposed to severe drought periods in 1999 and 2002 to retrospectively investigate drought response and the adaptive capacity of white spruce populations across their boreal range. Relying on dendrochronological analysis under experimentally controlled environments, we evaluate population differences in resistance, resilience, and recovery to these extreme events. Results showed evidence for population differentiation in resistance and recovery parameters, but provenances conformed to approximately the same growth rates under drought conditions and had similar resilience metrics. The lack of populations with better growth rates under drought conditions is contrary to expectations for a wide‐ranging species with distinct regional climates. Populations from the wettest environments in the northeastern boreal were surprisingly drought‐tolerant, suggesting that these populations would readily resist water deficits projected for the 2080s, and supporting the view that northeastern Canada will provide a refugium for boreal species under climate change. The findings also suggest that white spruce is sensitive to growth reductions under climate change in the western boreal. The study highlights that population differentiation in adaptive capacity is species‐ and trait‐specific, and we provide a counterexample for drought tolerance traits, where assisted migration prescriptions may be ineffective to mitigate climate change impacts. For resource managers and policy makers, we provide maps where planning for widespread declines of boreal white spruce forests may be unavoidable.
Temporal changes in fish diversity in lotic and lentic environments along a reservoir cascade
Authors: Loures Raquel Coelho , Pompeu Paulo Santos
Published: July 2019

Long‐term modifications in hydrological conditions due to river damming result in varied effects on fish diversity, which can be stronger in a reservoir cascade. Therefore, we assessed changes in fish diversity over a 28‐year period, in a series of reservoirs along the Araguari River Basin, a Neotropical drainage in Brazil, in both lentic environments (reservoirs) and the lotic stretches between them.

We used linear mixed models to assess long‐term changes in fish diversity. Diversity was measured as α diversity (fish species richness) and β diversity (Jaccard's and Raup–Crick's dissimilarity index). Beta diversity was then partitioned into turnover (species replacement) and nestedness (species loss). To understand fish species replacement along the cascade, we modelled turnover with four covariates: age, richness of native and non‐native fish species, and longitudinal position of sampling site along the cascade.

The reduction of total richness and the increase in non‐native richness were related to reservoir age. These effects were similar in both lotic and lentic environments, with no significant difference between them. We also observed a decrease in native fish richness over time, with a slight tendency for lentic environments to lose more species than lotic environments.

Dissimilarity in fish assemblage increased over time and β Raup–Crick results corroborated those derived from β Jaccard, yielding similar significant temporal trends. Changes in fish species composition occurred predominantly due to turnover, compared to nestedness. We observed a greater species loss in reservoirs, suggesting that the transformation from a lotic environment into a lentic had greater impact on fish assemblages than the flow regulation of the lotic stretches downstream of the dams. Our results suggest that species replacement can be explained mainly by the increase of non‐native fish richness, followed by the longitudinal position along the cascade in an upstream–downstream direction, and reservoir age.

This study reveals that, even after 2 decades of monitoring, we still observe important changes in fish assemblages, demonstrating the importance of long‐term monitoring to assess biodiversity. Our findings reinforce the importance of long‐term fish monitoring schemes for the investigation of the effects of non‐native fish species on native fish assemblages.
Happy Jack Uraninite: A New Reference Material for High Spatial Resolution Analysis of U‐Rich Matrices
Authors: Dorais Corinne , Simonetti Antonio , Corcoran Loretta , Spano Tyler L. , Burns Peter C.
Published: July 2019

There is currently a lack of well‐characterised matrix‐matched reference materials (RMs) for forensic analysis of U‐rich materials at high spatial resolution. This study reports a detailed characterisation of uraninite (nominally UO2+x) from the Happy Jack Mine (UT, USA). The Happy Jack uraninite can be used as a RM for the determination of rare earth element (REE) mass fractions in nuclear materials, which provide critical information for source attribution purposes. This investigation includes powder X‐ray diffraction (pXRD) data, as well as major, minor and trace element abundances determined using a variety of micro‐analytical techniques. The chemical signature of the uraninite was investigated at the macro (cm)‐scale with micro‐X‐ray fluorescence (µXRF) mapping and at high spatial resolution (tens of micrometre scale) using electron probe microanalysis (EPMA) and laser ablation‐inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS) analyses. Based on EPMA results, the uraninite is characterised by homogeneous UO2 and CaO contents of 91.57 ± 1.49% m/m (2s uncertainty) and 2.70 ± 0.38% m/m (2s), respectively. Therefore, CaO abundances were used as the internal standard when conducting LA‐ICP‐MS analyses. Overall, the major element and REE compositions are homogeneous at both the centimetre and micrometre scales, allowing this material to be used as a RM for high spatial resolution analysis of U‐rich samples.
Assessing dinner meals offered at home among preschoolers from low‐income families with the Remote Food Photography Method
Authors: Bekelman Traci A. , Bellows Laura L. , McCloskey Morgan L. , Martin Corby K. , Johnson Susan L.
Published: July 2019

Background

The high prevalence of obesity among preschoolers may be partially explained by the type and quantity of foods offered by parents and left unconsumed by preschoolers.

Objectives

(a) To compare foods offered and consumed at dinner to the Dietary Guidelines for Americans (DGAs) and the Child and Adult Care Food Program (CACFP) standards and (b) to examine the types, quantities, and nutrient composition of foods offered to and consumed by preschoolers and their plate waste.

Methods

Participants were recruited from six Head Start/preschool centres. The Remote Food Photography Method was used to document dinner meals over 1 week (n = 153 meals). Energy and nutrients for foods offered, consumed, and plate waste were calculated. Foods offered and consumed were compared with the DGAs and CACFP standards.

Results

Foods and beverages offered at dinner equaled 506 kcal, which is 36% of the DGA‐recommended total daily energy intake. Meals offered and consumed were high in fat and sodium and low in fibre. Adherence to CACFP standards was low for fruits (25%) and milk (2%) and moderate for vegetables (63%). Mean plate waste (29%) was similar across food types.

Conclusions

Opportunities exist to improve preschoolers' adherence to the DGAs and CACFP standards by enhancing the quality of dinner meals offered to them.
The behaviour of some antihypertension drugs on human serum paraoxonase-1: an important protector enzyme against atherosclerosis
Authors: Demir Yeliz
Published: July 2019

Objectives

Paraoxonase-1 (PON1) enzyme is related to high-density lipoprotein (HDL), which is calcium dependent. It has essential roles such as protecting LDL against oxidation and detoxification of highly toxic substances. It is a significant risk to reduce the levels of this enzyme in patients with diabetes mellitus, cardiovascular diseases, hyperthyroidism and chronic renal failure.

Methods

Here, it was reported that the purification of human serum PON1 using straightforward methods and determination of the interactions between some antihypertension drugs and the enzyme.

Key finding

It was found that these drugs exhibit potential inhibitor properties for human serum PON1 with IC50 values in the range of 131.40–369.40 μm and Ki values in the range of 56.24 ± 6.75–286.74 ± 28.28 μm. These drugs showed different inhibition mechanisms. It was determined that midodrine and nadolol were exhibited competitive inhibition, but atenolol and pindolol were exhibited non-competitive inhibition.

Conclusion

Usage of these drugs would be hazardous in some cases.
Incorporating Ploidy Diversity into Ecological and Community Genetics
Authors: Krueger‐Hadfield Stacy A. , Blakeslee April M. H. , Fowler Amy E.
Published: July 2019

Studies in ecological and community genetics have advanced our understanding of the role of intraspecific diversity in structuring communities and ecosystems. However, in near‐shore marine communities, these studies have mostly been restricted to seagrasses, marsh plants, and oysters. Yet, macroalgae are critically important ecosystem engineers in these communities. Greater intraspecific diversity in a macroalgal ecosystem engineer should result in higher primary and secondary production and community resilience. The paucity of studies investigating the consequences of macroalgal intraspecific genetic variation might be due, in part, to the complexity of macroalgal life cycles. The majority of macroalgae have seemingly subtle, but in actuality, profoundly different life cycles than the more typical animal and angiosperm models. Here, we develop a novel genetic diversity metric, PHD, that incorporates the ratio of gametophytic to sporophytic thalli in natural populations. This metric scales from 0 to 1 like many common genetic diversity metrics, such as genotypic richness, enabling comparisons among metrics. We discuss PHD and examples from the literature, with specific reference to the widespread, red seaweed Agarophyton vermiculophyllum. We also discuss a sex diversity metric, PFM, which also scales from 0 to 1, but fewer studies have identified males and females in natural populations. Nevertheless, by incorporating these novel metrics into the repertoire of diversity metrics, we can explore the role of genetic diversity in community and ecosystem dynamics with an emphasis on the unique biology of many macroalgae, as well as other haplodiplontic taxa such as ferns, foraminiferans, and some fungi.
Unique sleep‐stage transitions determined by obstructive sleep apnea severity, age and gender
Authors: Wächter Marcel , Kantelhardt Jan W. , Bonsignore Maria R. , Bouloukaki Izolde , Escourrou Pierre , Fietze Ingo , Grote Ludger , Korzybski Damian , Lombardi Carolina , Marrone Oreste , Paranicova Ivana , Pataka Athanasia , Ryan Silke , Schiza Sophia E. , Sliwinski Pawel , Steiropoulos Paschalis , Verbraecken Johan , Penzel Thomas ,   ESADA Study Group
Published: July 2019

In obstructive sleep apnea, patients’ sleep is fragmented leading to excessive daytime sleepiness and co‐morbidities like arterial hypertension. However, traditional metrics are not always directly correlated with daytime sleepiness, and the association between traditional sleep quality metrics like sleep duration and arterial hypertension is still ambiguous. In a development cohort, we analysed hypnograms from mild (n = 209), moderate (n = 222) and severe (n = 272) obstructive sleep apnea patients as well as healthy controls (n = 105) from the European Sleep Apnea Database. We assessed sleep by the analysis of two‐step transitions depending on obstructive sleep apnea severity and anthropometric factors. Two‐step transition patterns were examined for an association to arterial hypertension or daytime sleepiness. We also tested cumulative distributions of wake as well as sleep‐states for power‐laws (exponent α) and exponential distributions (decay time τ) in dependency on obstructive sleep apnea severity and potential confounders. Independent of obstructive sleep apnea severity and potential confounders, wake‐state durations followed a power‐law distribution, while sleep‐state durations were characterized by an exponential distribution. Sleep‐stage transitions are influenced by obstructive sleep apnea severity, age and gender. N2 → N3 → wake transitions were associated with high diastolic blood pressure. We observed higher frequencies of alternating (symmetric) patterns (e.g. N2 → N1 → N2, N2 → wake → N2) in sleepy patients both in the development cohort and in a validation cohort (n = 425). In conclusion, effects of obstructive sleep apnea severity and potential confounders on sleep architecture are small, but transition patterns still link sleep fragmentation directly to obstructive sleep apnea‐related clinical outcomes like arterial hypertension and daytime sleepiness.
Analysis of the technical efficiency of Nile perch (Lates niloticus) fishers in the Tanzanian portion of Lake Victoria: A stochastic frontier analysis
Authors: Mkuna Eliaza , Baiyegunhi Lloyd J. S.
Published: July 2019

The Nile perch fishery sector in Tanzania is important for enhancing the livelihoods and food security for the majority of people living near the Tanzanian portion of Lake Victoria. Despite continued government efforts and other institutions, including the Food and Agriculture Organization (FAO), Lake Victoria Fisheries Organization (LVFO), European Union and World Bank regarding the management of Lake Victoria, the Nile perch fishers have remained relative inefficient in regard to improving their fish catches. The Nile perch small‐scale fisheries sector in particular faces a challenge regarding how to improve production performance while, at the same time, ensuring a sustainable level of fisheries resources. This reality necessitates the measurement and analysis of artisan fishers’ technical efficiency. Accordingly, the present study analyses Nile perch fishers technical efficiency, using a stochastic production frontier (SPF) model based on the sample of 268 Nile perch fishers in the Tanzanian portion of Lake Victoria. The translog stochastic frontier model results indicate the technical efficiency of Nile perch fishers range between 61% and 80%, with an overall average technical efficiency of 75%. This finding implies that, based on existing fishery resources, the current quantity of Nile perch catch can be improved efficiently by 25%, a reality highlighting mismanagement of the lake's fishery resources. The quantity of bait and petrol and the number of hooks used per trip are the most important fishing inputs, indicating a positive Nile perch fishing output–input elasticity. To address the Nile perch fisher inefficiency, it is important to provide subsidized inputs such as outboard engines and mesh gillnets. Provision of access to affordable credits will enable fishers to purchase less destructive fishing inputs and improve the current structure of fishery organizations.