Influence of droplet coverage on the electrochemical response of planar microelectrodes and potential solving strategies based on nesting concept
Recently, biosensors have been widely used for the detection of bacteria, viruses and other toxins. Electrodes, as commonly used transducers, are a vital part of electrochemical biosensors. The coverage of the droplets can change significantly based on the hydrophobicity of the microelectrode surface materials. In the present research, screen-printed interdigitated microelectrodes (SPIMs), as one type of planar microelectrode, were applied to investigate the influence of droplet coverage on electrochemical response. Furthermore, three dimensional (3D) printing technology was employed to print smart devices with different diameters based on the nesting concept. Theoretical explanations were proposed to elucidate the influence of the droplet coverage on the electrochemical response. 3D-printed ring devices were used to incubate the SPIMs and the analytical performances of the SPIMs were tested. According to the results obtained, our device successfully improved the stability of the signal responses and eliminated irregular signal changes to a large extent. Our proposed method based on the nesting concept provides a promising method for the fabrication of stable electrochemical biosensors. We also introduced two types of electrode bases to improve the signal stability.
Yu et al. (2016) Influence of droplet coverage on the electrochemical response of planar microelectrodes and potential solving strategies based on nesting concept. PeerJ 4:e2400 https://doi.org/10.7717/peerj.2400
Effect of pillow height on the biomechanics of the head-neck complex: investigation of the cranio-cervical pressure and cervical spine alignment
Background While appropriate pillow height is crucial to maintaining the quality of sleep and overall health, there are no universal, evidence-based guidelines for pillow design or selection. We aimed to evaluate the effect of pillow height on cranio-cervical pressure and cervical spine alignment. Methods Ten healthy subjects (five males) aged 26 ± 3.6 years were recruited. The average height, weight, and neck length were 167 ± 9.3 cm, 59.6 ± 11.9 kg, and 12.9 ± 1.2 cm respectively. The subjects lay on pillows of four different heights (H0, 110 mm; H1, 130 mm; H2, 150 mm; and H3, 170 mm). The cranio-cervical pressure distribution over the pillow was recorded; the peak and average pressures for each pillow height were compared by one-way ANOVA with repeated measures. Cervical spine alignment was studied using a finite element model constructed based on data from the Visible Human Project. The coordinate of the center of each cervical vertebra were predicted for each pillow height. Three spine alignment parameters (cervical angle, lordosis distance and kyphosis distance) were identified. Results The average cranial pressure at pillow height H3 was approximately 30% higher than that at H0, and significantly different from those at H1 and H2 (p < 0.05). The average cervical pressure at pillow height H0 was 65% lower than that at H3, and significantly different from those at H1 and H2 (p < 0.05). The peak cervical pressures at pillow heights H2 and H3 were significantly different from that at H0 (p < 0.05). With respect to cervical spine alignment, raising pillow height from H0 to H3 caused an increase of 66.4% and 25.1% in cervical angle and lordosis distance, respectively, and a reduction of 43.4% in kyphosis distance. Discussion Pillow height elevation significantly increased the average and peak pressures of the cranial and cervical regions, and increased the extension and lordosis of the cervical spine. The cranio-cervical pressures and cervical spine alignment were height-specific, and they were believed to reflect quality of sleep. Our results provide a quantitative and objective evaluation of the effect of pillow height on the biomechanics of the head-neck complex, and have application in pillow design and selection.
Ren et al. (2016) Effect of pillow height on the biomechanics of the head-neck complex: investigation of the cranio-cervical pressure and cervical spine alignment. PeerJ 4:e2397 https://doi.org/10.7717/peerj.2397
Effect of 8-hydroxyquinoline and derivatives on human neuroblastoma SH-SY5Y cells under high glucose
8-Hydroxyquinoline and derivatives exhibit multifunctional properties, including antioxidant, antineurodegenerative, anticancer, anti-inflammatory and antidiabetic activities. In biological systems, elevation of intracellular calcium can cause calpain activation, leading to cell death. Here, the effect of 8-hydroxyquinoline and derivatives (5-chloro-7-iodo-8-hydroxyquinoline or clioquinol and 8-hydroxy-5-nitroquinoline or nitroxoline) on calpain-dependent (calpain-calpastatin) pathways in human neuroblastoma (SH-SY5Y) cells was investigated. 8-Hydroxyquinoline and derivatives ameliorated high glucose toxicity in SH-SY5Y cells. The investigated compounds, particularly clioquinol, attenuated the increased expression of calpain, even under high-glucose conditions. 8-Hydroxyquinoline and derivatives thus adversely affected the promotion of neuronal cell death by high glucose via the calpain-calpastatin signaling pathways. These findings support the beneficial effects of 8-hydroxyquinolines for further therapeutic development.
Suwanjang et al. (2016) Effect of 8-hydroxyquinoline and derivatives on human neuroblastoma SH-SY5Y cells under high glucose. PeerJ 4:e2389 https://doi.org/10.7717/peerj.2389
Genome-wide identification and characterization of GRAS transcription factors in sacred lotus (Nelumbo nucifera)
The GRAS gene family is one of the most important plant-specific gene families, which encodes transcriptional regulators and plays an essential role in plant development and physiological processes. The GRAS gene family has been well characterized in many higher plants such as Arabidopsis, rice, Chinese cabbage, tomato and tobacco. In this study, we identified 38 GRAS genes in sacred lotus (Nelumbo nucifera), analyzed their physical and chemical characteristics and performed phylogenetic analysis using the GRAS genes from eight representative plant species to show the evolution of GRAS genes in Planta. In addition, the gene structures and motifs of the sacred lotus GRAS proteins were characterized in detail. Comparative analysis identified 42 orthologous and 9 co-orthologous gene pairs between sacred lotus and Arabidopsis, and 35 orthologous and 22 co-orthologous gene pairs between sacred lotus and rice. Based on publically available RNA-seq data generated from leaf, petiole, rhizome and root, we found that most of the sacred lotus GRAS genes exhibited a tissue-specific expression pattern. Eight of the ten PAT1-clade GRAS genes, particularly NnuGRAS-05, NnuGRAS-10 and NnuGRAS-25, were preferentially expressed in rhizome and root. In summary, this is the first in silico analysis of the GRAS gene family in sacred lotus, which will provide valuable information for further molecular and biological analyses of this important gene family.
Wang et al. (2016) Genome-wide identification and characterization of GRAS transcription factors in sacred lotus (Nelumbo nucifera). PeerJ 4:e2388 https://doi.org/10.7717/peerj.2388
Evolution of the climatic tolerance and postglacial range changes of the most primitive orchids (Apostasioideae) within Sundaland, Wallacea and Sahul
The location of possible glacial refugia of six Apostasioideae representatives is estimated based on ecological niche modeling analysis. The distribution of their suitable niches during the last glacial maximum (LGM) is compared with their current potential and documented geographical ranges. The climatic factors limiting the studied species occurrences are evaluated and the niche overlap between the studied orchids is assessed and discussed. The predicted niche occupancy profiles and reconstruction of ancestral climatic tolerances suggest high level of phylogenetic niche conservatism within Apostasioideae.
Kolanowska et al. (2016) Evolution of the climatic tolerance and postglacial range changes of the most primitive orchids (Apostasioideae) within Sundaland, Wallacea and Sahul. PeerJ 4:e2384 https://doi.org/10.7717/peerj.2384
Aquatic insects dealing with dehydration: do desiccation resistance traits differ in species with contrasting habitat preferences?
Background Desiccation resistance shapes the distribution of terrestrial insects at multiple spatial scales. However, responses to drying stress have been poorly studied in aquatic groups, despite their potential role in constraining their distribution and diversification, particularly in arid and semi-arid regions. Methods We examined desiccation resistance in adults of four congeneric water beetle species (Enochrus, family Hydrophilidae) with contrasting habitat specificity (lentic vs. lotic systems and different salinity optima from fresh- to hypersaline waters). We measured survival, recovery capacity and key traits related to desiccation resistance (fresh mass, % water content, % cuticle content and water loss rate) under controlled exposure to desiccation, and explored their variability within and between species. Results Meso- and hypersaline species were more resistant to desiccation than freshwater and hyposaline ones, showing significantly lower water loss rates and higher water content. No clear patterns in desiccation resistance traits were observed between lotic and lentic species. Intraspecifically, water loss rate was positively related to specimens’ initial % water content, but not to fresh mass or % cuticle content, suggesting that the dynamic mechanism controlling water loss is mainly regulated by the amount of body water available. Discussion Our results support previous hypotheses suggesting that the evolution of desiccation resistance is associated with the colonization of saline habitats by aquatic beetles. The interespecific patterns observed in Enochrus also suggest that freshwater species may be more vulnerable than saline ones to drought intensification expected under climate change in semi-arid regions such as the Mediterranean Basin.
Pallarés et al. (2016) Aquatic insects dealing with dehydration: do desiccation resistance traits differ in species with contrasting habitat preferences?. PeerJ 4:e2382 https://doi.org/10.7717/peerj.2382
Knowledge of blood loss at delivery among postpartum patients
Background Postpartum hemorrhage (PPH) is a leading cause of obstetric morbidity. There is limited understanding of patients’ knowledge about blood loss at delivery, PPH, and PPH-related morbidities, including transfusion and anemia. Methods We surveyed 100 healthy postpartum patients who underwent vaginal or cesarean delivery about blood loss, and whether they received information about transfusion and peripartum hemoglobin (Hb) testing. Responses were compared between women undergoing vaginal delivery vs. cesarean delivery; P < 0.05 considered as statistically significant. Results In our cohort, 49 women underwent vaginal delivery and 51 women underwent cesarean delivery. Only 29 (29%) of women provided blood loss estimates for their delivery. Women who underwent cesarean delivery were more likely to receive clear information about transfusion therapy than those undergoing vaginal delivery (43.1% vs. 20.4% respectively; P = 0.04). Women who underwent vaginal delivery were more likely to receive results of postpartum Hb tests compared to those undergoing cesarean delivery (49% vs. 29.4%; P = 0.02). Conclusion Our findings suggest that women are poorly informed about the magnitude of blood loss at delivery. Hematologic information given to patients varies according to mode of delivery. Further research is needed to better understand the clinical implications of patients’ knowledge gaps about PPH, transfusion and postpartum anemia.
Farber et al. (2016) Knowledge of blood loss at delivery among postpartum patients. PeerJ 4:e2361 https://doi.org/10.7717/peerj.2361
Psychological distress of residents in Kawauchi village, Fukushima Prefecture after the accident at Fukushima Daiichi Nuclear Power Station: the Fukushima Health Management Survey
Background To shed light on the mental health of evacuees after the accident at Fukushima Daiichi Nuclear Power Station (FDNPS), we evaluate the results of the Fukushima Health Management Survey (FHMS) of the residents at Kawauchi village in Fukushima, which is located less than 30 km from the FDNPS. Methods We conducted the cross-sectional study within the framework of the FHMS. Exposure values were “anorexia,” “subjective feelings about health,” “feelings about sleep satisfaction,” and “bereavement caused by the disaster,” confounding variables were “age” and “sex,” and outcome variables were “K6 points.” We collected data from the FHMS, and employed the Kessler Psychological Distress Scale (K6) and the posttraumatic stress disorder (PTSD) Checklist Stressor-Specific Version (PCL-S) to carry out the research. A total of 13 or greater was the cut-off for identifying serious mental illness using the K6 scale. The study subjects included residents (n = 542) of over 30 years of age from Kawauchi village, and data were used from the period of January 1, 2012 to October 31, 2012. Results A total of 474 residents (87.5%) scored less than 13 points in the K6 and 68 (12.6%) scored 13 points or more. The proportion of elderly residents (over 65 years old) among people with K6 score above the cut-off was higher than that among people with K6 score below the cut-off (44.1 vs 31.0%, p < 0.05). In addition, the proportion of residents with anorexia and mental illness among people with K6 score above the cut-off was higher than among people with K6 score below the cut-off (p < 0.001 and p < 0.05, respectively). The amount of residents who scored 44 points or more in the PCL-S among people with K6 score above the cut-off was also considerably higher than among people with K6 score below the cut-off (79.4 vs 12.9%, p < 0.001). Interestingly, the proportion of residents who scored more than among people with K6 score above the cut-off and the among people with PCL-S score above the cut-off in Kawauchi was higher than in previous studies in other locations. Conclusions These results suggest that there are severe mental health problems, such as depression and PTSD, among adults as a consequence of the accident at the FDNPS. Our study showed that residents who lived in the evacuation zone before the disaster are at high risk psychological distress. To facilitate local residents’ recovery from Fukushima, there is a need to continue providing them with physical and mental support, as well as communication regarding the health risks of radiation.
Yoshida et al. (2016) Psychological distress of residents in Kawauchi village, Fukushima Prefecture after the accident at Fukushima Daiichi Nuclear Power Station: the Fukushima Health Management Survey. PeerJ 4:e2353 https://doi.org/10.7717/peerj.2353
Joint estimation of crown of thorns (Acanthaster planci) densities on the Great Barrier Reef
Crown-of-thorns starfish (CoTS; Acanthaster spp.) are an outbreaking pest among many Indo-Pacific coral reefs that cause substantial ecological and economic damage. Despite ongoing CoTS research, there remain critical gaps in observing CoTS populations and accurately estimating their numbers, greatly limiting understanding of the causes and sources of CoTS outbreaks. Here we address two of these gaps by (1) estimating the detectability of adult CoTS on typical underwater visual count (UVC) surveys using covariates and (2) inter-calibrating multiple data sources to estimate CoTS densities within the Cairns sector of the Great Barrier Reef (GBR). We find that, on average, CoTS detectability is high at 0.82 [0.77, 0.87] (median highest posterior density (HPD) and [95% uncertainty intervals]), with CoTS disc width having the greatest influence on detection. Integrating this information with coincident surveys from alternative sampling programs, we estimate CoTS densities in the Cairns sector of the GBR averaged 44 [41, 48] adults per hectare in 2014.
MacNeil et al. (2016) Joint estimation of crown of thorns (Acanthaster planci) densities on the Great Barrier Reef. PeerJ 4:e2310 https://doi.org/10.7717/peerj.2310
A Jurassic pterosaur from Patagonia and the origin of the pterodactyloid neurocranium
Pterosaurs are an extinct group of highly modified flying reptiles that thrived during the Mesozoic. This group has unique and remarkable skeletal adaptations to powered flight, including pneumatic bones and an elongate digit IV supporting a wing-membrane. Two major body plans have traditionally been recognized: the primitive, primarily long-tailed paraphyletic “rhamphorhynchoids” (preferably currently recognized as non-pterodactyloids) and the derived short-tailed pterodactyloids. These two groups differ considerably in their general anatomy and also exhibit a remarkably different neuroanatomy and inferred head posture, which has been linked to different lifestyles and behaviours and improved flying capabilities in these reptiles. Pterosaur neuroanatomy, is known from just a few three-dimensionally preserved braincases of non-pterodactyloids (as Rhamphorhynchidae) and pterodactyloids, between which there is a large morphological gap. Here we report on a new Jurassic pterosaur from Argentina, Allkaruen koi gen. et sp. nov., remains of which include a superbly preserved, uncrushed braincase that sheds light on the origins of the highly derived neuroanatomy of pterodactyloids and their close relatives. A µCT ray-generated virtual endocast shows that the new pterosaur exhibits a mosaic of plesiomorphic and derived traits of the inner ear and neuroanatomy that fills an important gap between those of non-monofenestratan breviquartossans (Rhamphorhynchidae) and derived pterodactyloids. These results suggest that, while modularity may play an important role at one anatomical level, at a finer level the evolution of structures within a module may follow a mosaic pattern.
Codorniú et al. (2016) A Jurassic pterosaur from Patagonia and the origin of the pterodactyloid neurocranium. PeerJ 4:e2311 https://doi.org/10.7717/peerj.2311