bluuebunny/crossref_metadata_2025 huggingface dataset:
Drought intensification alters the composition, body size, and trophic structure of invertebrate assemblages in a stream mesocosm experiment
Authors: Aspin Thomas W. H. , Hart Kris , Khamis Kieran , Milner Alexander M. , O'Callaghan Matthew J. , Trimmer Mark , Wang Zining , Williams Gavin M. D. , Woodward Guy , Ledger Mark E.
Published: February 2019

Predicted trends towards more intense droughts are of particular significance for running water ecosystems, as the loss of critical stream habitat can provoke sudden changes in biodiversity and shifts in community structure. However, analysing ecological responses to the progressive loss of stream habitat requires a continuous disturbance gradient that can only be generated through large‐scale manipulations of streamflow.

In the first experiment of its kind, we used large artificial stream channels (mesocosms) as analogues of spring‐fed headwaters and simulated a gradient of drought intensity that encompassed flowing streams, disconnected pools, and dry streambeds. We used breakpoint analysis to analyse macroinvertebrate community responses to intensifying drought, and identify the taxa and compositional metrics sensitive to small changes in drought stress.

We detected breakpoints for >60% of taxa, signalling sudden population crashes or irruptions as drought intensified. Abrupt changes were most pronounced where riffle dewatering isolated pools. In the remnant wetted habitat, we observed a shift to larger body sizes across the community, primarily driven by irruptions of predatory midge larvae and coincident population collapses among prey species (worms and smaller midges).

Our results suggest that intense predation in confined, fragmented stream habitat can lead to unexpected changes in body sizes, challenging the conventional wisdom that droughts favour the small. Pool fragmentation might thus be the most critical stage of habitat loss during future droughts, as the point at which impacted rivers and streams begin to exhibit major shifts in fundamental food web properties.
Spatial overlaps between the global protected areas network and terrestrial hotspots of evolutionary diversity
Authors: Daru Barnabas H. , le Roux Peter C. , Gopalraj Jeyanthi , Park Daniel S. , Holt Ben G. , Greve Michelle
Published: February 2019

Aim

A common approach for prioritizing conservation is to identify concentrations (hotspots) of biodiversity. Such hotspots have traditionally been designated on the basis of species‐level metrics (e.g., species richness, endemism and extinction vulnerability). These approaches do not consider phylogenetics explicitly, although phylogenetic relationships reflect the ecological, evolutionary and biogeographical processes by which biodiversity is generated, distributed and maintained. The aim of this study was to identify hotspots of phylogenetic diversity and compare these with hotspots based on species‐level metrics and with the existing protected areas network.

Location

Global.

Time period

Contemporary.

Major taxa studied

Terrestrial vertebrates (mammals, birds and amphibians) and angiosperms.

Methods

We used comprehensive phylogenies and distribution maps of terrestrial birds, mammals, amphibians and angiosperms to identify areas with high concentrations of phylogenetic diversity, phylogenetic endemism, and evolutionary distinctiveness and global endangerment. We compared the locations of these areas with those included within the current network of protected areas and concentrations of species‐level indices: species richness, species endemism and species threat.

Results

We found spatial incongruence among the three evolutionary diversity metrics in each taxonomic group. Spatial patterns of diversity and endemism also differed among taxonomic groups, with some differences between vertebrates and angiosperms. Complementarity analyses of phylogenetic diversity identified the minimal area that encapsulates the full branch lengths for each taxonomic group. The current network of protected areas and species‐level hotspots largely does not overlap with areas of high phylodiversity.

Main conclusion

Overall, < 10% of hotspot areas were designated as protected areas. Patterns of diversity, endemism and vulnerability differ among taxonomic groups.
A relationship of intradialytic blood pressure variability with vascular access outcomes in patients on hemodialysis
Authors: Kim Ji Young , Seo Hye Mi , Kim Miyeon , Kim Hyunwoo
Published: February 2019

Introduction: Vascular access dysfunction is a major cause of morbidity in patients with end‐stage renal disease (ESRD) on hemodialysis (HD). Thus, identifying risk factors for vascular access failure is important. Patients on HD are routinely exposed to high blood pressure variability (BPV) during HD. However, the impact of intradialytic BPV on vascular access outcomes is unknown. Therefore, we investigated the association of intradialytic BPV with vascular access outcomes in patients on HD.

Methods: One hundred and thirty patients with ESRD who created vascular access for HD were evaluated. We examined 12 dialysis sessions per patient and recorded BP five times for each session. BPV was assessed using residual standard deviation derived from the linear regression model. The patients were divided into two groups according to a level below or above the median value of intradialytic BPV and compared. The primary outcome was primary unassisted vascular access patency.

Findings: The median time to loss of primary unassisted patency was significantly longer in low intradialytic BPV group than in high intradialytic BPV group (52 months vs. 21 months, P < 0.001) during the mean follow‐up of 3.7 years. After adjustment for other variables, high intradialytic BPV was significantly associated with loss of primary unassisted vascular access patency (hazard ratio, 2.605; 95% confidence interval, 1.462–4.643; P = 0.001).

Discussion: Our study revealed a significant correlation between intradialytic BPV and vascular access patency. Further studies are needed to identify methods for lowering BPV.
Developing personal sense of risk: a grounded theory in men with hypertension
Authors: Seesawang J. , Bowers B. , Sansiriphun N.
Published: February 2019

Background

For older men with hypertension living in rural areas, non‐adherence to treatment is a common phenomenon. The experience on risk perception of individuals with their condition is recognized as playing a critical role in promoting treatment adherence. However, the experience on risk perception in a cohort of older men with hypertension seems unclear.

Aim

To develop a theory concerning risk perception experience in a cohort of older men with hypertension from a rural area of Thailand.

Methods

A grounded theory approach was used. Semi‐structured, face‐to‐face interviews with 29 hypertensive older men were conducted in Thailand using purposive and theoretical sampling methods. The grounded theory analytical method that included initial and focused coding, and constant comparison was used to analyse the data.

Findings

‘Developing a personal sense of risk’ emerged as a core category, which incorporated the related four subprocesses: comparing healthcare provider information with stories of people with hypertension, comparing one's own situation with stories of people with hypertension, changing personal sense of risk and changing risk‐related behaviour. Older men selected to focus on one particular outcome, using the selected outcome to monitor their risk.

Conclusion

This investigation provides a theory for healthcare providers to understand older men's perceptions of personal risk for complications of hypertension. A personal sense of risk influences risk‐related behaviour change.

Implications for nursing and health policy

The findings can be used in assessing a personal sense of risk and promoting treatment adherence in older men with hypertension. Effective storytelling intervention, a standard tool for assessment personal sense of risk in older men with hypertension, should be developed. Hypertension care policy needs to be developed for individualized approaches.
Testing cross‐lagged relationships between work‐related rumination and well‐being at work in a three‐wave longitudinal study across 1 and 2 years
Authors: Kinnunen Ulla , Feldt Taru , de Bloom Jessica
Published: February 2019

The aim of this three‐wave longitudinal study conducted among 664 Finnish employees was to examine the cross‐lagged relationships between various work‐related ruminative thoughts (affective rumination, problem‐solving pondering, lack of detachment from work) during off‐job time and employee well‐being (exhaustion, vigour). We tested normal, reversed, and reciprocal temporal relationships across 1 and 2 years using structural equation modelling. The analyses lent most support to the reversed temporal relationships, showing first that high exhaustion predicted low problem‐solving pondering 2 years later and second, that high vigour predicted low affective rumination both 1 and 2 years later. In addition, a normal temporal relationship was supported in one model, indicating that high affective rumination predicted high exhaustion 1 year later. Thus, our study suggests that affective ruminative thoughts, in particular, play a negative role in cross‐lagged relationships. On the basis of our results, occupational health interventions intended to reduce both affective work‐related rumination and exhaustion and to increase vigour at work are desirable.

Practitioner points

Affective rumination during off‐job time predicted increased job exhaustion across 1 year. Prevent affective rumination by training employees to change ways of thinking and to create action plans on setting and completing work goals.

Vigour predicted reduced affective work‐related rumination in the long term. Provide employees with sufficient job resources to increase their vigour at work.

Exhaustion predicted reduced problem‐solving pondering during off‐job time in the long term. Attention should be paid to ensuring that job demands are not so high that they increase exhaustion. Care should be taken to ensure that problem‐solving pondering replenishes energy resources.
Effects of dietary resveratrol supplementation during gestation and lactation of sows on milk composition of sows and fat metabolism of sucking piglets
Authors: Sun Shishuai , Meng Qingwei , Luo Zhang , Shi Baoming , Bi Chongpeng , Shan Anshan
Published: February 2019

The purpose of this article was to investigate the effects of dietary resveratrol supplementation during gestation and lactation of sows on the milk composition of sows and the fat metabolism of sucking piglets. Forty sows were allotted to two experimental treatment groups that included the following: (a) control sows (CON treatment, n = 20) fed with a corn–soybean meal control diet and (b) treatment sows (RES treatment, n = 20) fed with a control diet with addition of 300 mg/kg resveratrol. The results showed that the content of lactose in the colostrum was increased (p < 0.05) and the content of fat in 21‐day milk was increased (p < 0.05) by dietary resveratrol supplementation. In the RES treatment group, the concentrations of high‐density lipoprotein‐cholesterol (HDL‐C), low‐density lipoprotein‐cholesterol (LDL‐C), lipase activity and insulin (INS) in plasma of sucking piglets were increased (p < 0.05). In the adipose tissue, the enzyme activities of hormone‐sensitive lipase (HSL), acetyl‐CoA carboxylase (ACC) and lipoprotein lipase (LPL) increased significantly by RES treatment (p < 0.05), and the mRNA levels of acetyl coenzyme A‐alpha (ACCα), LPL, fatty acid transport protein (FATP1) and CCAAT–enhancer‐binding protein gene (C/EBPα) were higher in the RES treatment group (p < 0.05). In conclusion, resveratrol supplementation on gestational and lactating sows improved the content of lactose in the colostrum and the content of fat in milk at day 21 of lactation. In addition, resveratrol supplementation on sows increased HDL and LDL in the plasma of piglets. In piglet adipose tissue, the enzyme activity and mRNA level related to lipolysis, fatty acid uptake from circulating triacylglycerols and lipogenesis are partially improved by resveratrol supplementation on sows. These aspects affect fat metabolism in piglets.
The role of psychological factors in pediatric functional abdominal pain disorders
Authors: Newton Emily , Schosheim Alex , Patel Samit , Chitkara Denesh K. , van Tilburg Miranda A. L.
Published: February 2019

Background

Pediatric functional abdominal pain disorders (FAPDs) are disorders of brain‐gut dysregulation. Psychological factors are known to be related to etiology, maintenance, and exacerbation of pediatric FAPDs. With the evolving literature in the past two decades, a better understanding has emerged of precisely which psychological factors are associated with childhood FAPDs.

Purpose

This narrative literature review summarizes the literature of both child and parent psychological factors in pediatric FAPD. Where anxiety and depression were major targets in the older literature, present‐day focus is increasingly on pain‐specific cognitions and coping strategies including disease threat and catastrophizing. In addition, parental reaction to a child's pain is increasingly recognized as an important moderator of a child's outcomes and has become an area for clinical intervention. Screening for these factors and integrative treatment approaches are recommended in childhood FAPD.
Not the same old(‐growth) forests
Authors: Longo Marcos , Keller Michael
Published: February 2019

This article is a Commentary on Both et al., 221: 1853–1865.
Basal cell ameloblastoma in a paediatric patient: a case report and review of oral basal cell tumours
Authors: Kazakydasan S. , Zamhari A.K. , Achol L.T.
Published: February 2019

Basal cell ameloblastoma (BCA) is a rare histological variant of ameloblastoma. It is composed of densely packed nests and strands of basaloid cells with inconspicuous stellate reticulum‐like cells. To date, there are only 24 reported cases of BCA in the English language literature. Ameloblastoma in children is relatively an uncommon tumour and accounts for approximately 15% among all odontogenic tumours. We report a case of BCA in an 8‐year‐old Iban girl who underwent hemimandibulectomy and reconstruction of the mandible with costochondral graft (CCG). A 6 months review showed that healing process was uneventful. She is under regular follow‐up and monitoring since multicystic ameloblastoma tend to recur and also the growth of the CCG is extremely unpredictable.
Diffuse and canalicular patterns of glypican‐3 expression reflect malignancy of hepatocellular carcinoma
Authors: Kawaida Miho , Yamazaki Ken , Tsujikawa Hanako , Fukuma Mariko , Abe Yuta , Kitago Minoru , Shinoda Masahiro , Kitagawa Yuko , Sakamoto Michiie
Published: February 2019

Glypican‐3 (GPC3) is expressed in most hepatocellular carcinomas (HCCs). To investigate the significance of various GPC3 staining patterns in HCC, we classified 134 HCC patients into three groups: those with diffuse GPC3 staining, canalicular GPC3 staining, and others (including negative staining). HCCs with diffuse staining were correlated with poor differentiation, high Ki‐67 indices, high serum α‐fetoprotein (AFP) levels, and early recurrence. In contrast, HCCs with canalicular staining were well differentiated with lower AFP levels. Overall survival in this group was better than that of the other two groups. Comparative analysis of GPC3 staining patterns with markers for HCC subclassification showed that diffuse staining was correlated with the expression of biliary/stem cell markers, whereas canalicular staining was correlated with expression of the markers of WNT‐activated HCCs. Induction of leucine‐rich repeat‐containing G‐protein‐coupled receptor 5 (LGR5), known as a target of the WNT signaling pathway, in HCC cells resulted in reduced GPC3 expression in vitro. The LGR5‐induced cells formed tumors with canaliculus‐like structures in mice and showed canalicular GPC3 staining. The current findings showed the significance of recognizing distinct GPC3 staining patterns, i.e., diffuse and canalicular, which may reflect different carcinogenetic mechanisms and indicate the level of malignancy of HCC.
Overexpression of matriptase in tumor stroma is a poor prognostic indicator of extrahepatic bile duct cancer
Authors: Komatsubara Toshihide , Oshiro Hisashi , Sakuma Yasunaru , Sata Naohiro , Niki Toshiro , Fukushima Noriyoshi
Published: February 2019

Bile duct cancer is known to contain numerous fibroblasts, and reported to recruit cancer‐ associated fibroblasts by secreting platelet‐derived growth factor‐D (PDGF‐D) which needs serine proteases, such as matriptase, to behave as a ligand. However, their expression pattern, and prognostic value have not been clarified. In this study, we investigated the clinicopathological significance of PDGF‐D and matriptase expression in patients with extrahepatic bile duct cancer. The samples were obtained from 256 patients who underwent the surgical resection between 1991 and 2015, and the expression levels of PDGF‐D and matriptase were evaluated immunohistochemically. Staining intensities and distribution were scored, and finally classified into low and high expression groups in cancer cells and stroma respectively. High expression of matriptase in the cancer stroma was detected in 91 tumors (40%). The high stromal matriptase expression was significantly associated with shorter recurrence‐free survival (RFS) and overall survival (OS) (P = 0.0027 and 0.0023, respectively). Multivariate analyses also demonstrated that the stromal matriptase expression level was an independent influential factor in RFS (P = 0.0050) and OS (P = 0.0093). Our findings suggest that the high stromal matriptase expression was strongly associated with tumor progression, recurrence and poor outcomes in patients with extrahepatic bile duct cancer.
Kinetics of Helios(+) and Helios(−) T regulatory cell subsets in the circulation of healthy pregnant women
Authors: Kopřivová Helena , Hájková Michaela , Koucký Michal , Malíčková Karin , Holáň Vladimír , Krulová Magdalena
Published: February 2019

Regulatory T cells (Tregs) play a critical role in the maintenance of a pregnancy. While the kinetics of the number of peripheral blood Tregs has been satisfactorily described in mouse models, analysis of these cell populations in human pregnancy is complicated by high variability in the quantity of Tregs and inconsistencies in the markers used for detecting different types of Treg. In the light of this, we set out to investigate the kinetics of various types of Treg, including CD45RA, GARP and PD‐1(+) Tregs, in the peripheral blood of pregnant women in the first, second and third trimester, and at the time of delivery. Tregs, defined as a CD4(+)CD25(++)CD127(dim)Foxp3(+) population of leucocytes, were detected using flow cytometry. Natural thymus‐derived Tregs and induced Tregs in the peripheral blood were distinguished by the expression or absence of a Helios marker, respectively. Our results showed that during normal pregnancy the sizes of various Treg subpopulations varied across women and also in an individual woman did not remain constant but varied significantly, most notable being the decrease observed at the time of delivery. Helios(−) cells were significantly less frequent in the peripheral blood of healthy pregnant women than Helios(+) cells, and the majority of Tregs were Helios(+)PD‐1(+) Tregs.
Deliberation and Complexity of Thinking. Using the Integrative Complexity Scale to Assess the Deliberative Quality of Minipublics
Authors: Jennstål Julia
Published: February 2019

The quality of deliberative conversations are dependent on citizens compliance with deliberative norms yet there is a lack of methods to assess norm compliance in discussions. Here, the psychological construct of complexity of thinking is claimed to conceptually correspond to the deliberative conversational ideal and adopted as a measurement of deliberative norm compliance. The hypothesis that citizens' complexity of thinking increases as a result of participation in deliberative conversations was tested in a minipublic case study in Sweden. Participants' complexity of thinking was assessed before and after deliberation by responding to an open‐ended question about the topic of debate. Manual coding was used to rate participants integrative complexity. The result confirms the hypothesis, which serves as an indicator of deliberative quality. The study also demonstrates that women get higher increases in complexity, as do highly agreeable individuals and those who hold more liberal views. The findings demonstrate the potential usefulness of integrative complexity as a measurement of deliberative quality.
Characterization of the novel HLA‐C*07:708 allele by sequencing‐based typing
Authors: Cargou Marine , Andreani Marco , Battarra Mariarosa , Guidicelli Gwendaline , Visentin Jonathan
Published: February 2019

HLA‐C*07:708 differs from HLA‐C*07:01:01:01 by one nucleotide substitution at codon 258 in exon 4.
International haemovigilance: what have we learned and what do we need to do next?
Authors: Wood E. M. , Ang A. L. , Bisht A. , Bolton‐Maggs P. H. , Bokhorst A. G. , Flesland O. , Land K. , Wiersum‐Osselton J. C. , Schipperus M. R. , Tiberghien P. , Whitaker B. I.
Published: February 2019

The International Haemovigilance Network (IHN) defines haemovigilance as ‘a set of surveillance procedures covering the whole transfusion chain (from the collection of blood and its components to the follow‐up of recipients), intended to collect and assess information on unexpected or undesirable effects resulting from the therapeutic use of labile blood products, and to prevent their occurrence or recurrence’. IHN, the International Society of Blood Transfusion and World Health Organization work together to support both developing and established haemovigilance systems.

Haemovigilance systems provide valuable data on a range of adverse events related to blood donation and clinical transfusion, from donor syncopal events to transfusion‐transmitted infections, immunological complications and the impact of human errors. Harmonised definitions for most adverse reactions have been developed and validated internationally. Definitions of pulmonary complications are again under review.

Haemovigilance data have resulted in changes in policy, products and practice, and can complement and inform clinical audit and research, leading to improved blood donor safety, optimised product use and better clinical outcomes after transfusion.

However, more work is needed. Not all countries have haemovigilance systems in place. More robust data and careful analysis are required to improve the understanding of the causes, occurrence and clinical outcomes of these events. Wider dissemination of results will facilitate health policy development internationally, and implementation of haemovigilance recommendations will support further important progress in blood safety.
ABA inhibits myristoylation and induces shuttling of the RGLG1 E3 ligase to promote nuclear degradation of PP2CA
Authors: Belda‐Palazon Borja , Julian Jose , Coego Alberto , Wu Qian , Zhang Xu , Batistic Oliver , Alquraishi Saleh A. , Kudla Joerg , An Chengcai , Rodriguez Pedro L.
Published: February 2019

Hormone‐ and stress‐induced shuttling of signaling or regulatory proteins is an important cellular mechanism to modulate hormone signaling and cope with abiotic stress. Hormone‐induced ubiquitination plays a crucial role to determine the half‐life of key negative regulators of hormone signaling. For ABA signaling, the degradation of clade‐A PP2Cs, such as PP2CA or ABI1, is a complementary mechanism to PYR/PYL/RCAR‐mediated inhibition of PP2C activity. ABA promotes the degradation of PP2CA through the RGLG1 E3 ligase, although it is not known how ABA enhances the interaction of RGLG1 with PP2CA given that they are predominantly found in the plasma membrane and the nucleus, respectively. We demonstrate that ABA modifies the subcellular localization of RGLG1 and promotes nuclear interaction with PP2CA. We found RGLG1 is myristoylated in vivo, which facilitates its attachment to the plasma membrane. ABA inhibits the myristoylation of RGLG1 through the downregulation of N‐myristoyltransferase 1 (NMT1) and promotes nuclear translocation of RGLG1 in a cycloheximide‐insensitive manner. Enhanced nuclear recruitment of the E3 ligase was also promoted by increasing PP2CA protein levels and the formation of RGLG1–receptor–phosphatase complexes. We show that RGLG1Gly2Ala mutated at the N‐terminal myristoylation site shows constitutive nuclear localization and causes an enhanced response to ABA and salt or osmotic stress. RGLG1/5 can interact with certain monomeric ABA receptors, which facilitates the formation of nuclear complexes such as RGLG1–PP2CA–PYL8. In summary, we provide evidence that an E3 ligase can dynamically relocalize in response to both ABA and increased levels of its target, which reveals a mechanism to explain how ABA enhances RGLG1–PP2CA interaction and hence PP2CA degradation.
Factors affecting lymphocyte collection efficiency for the manufacture of chimeric antigen receptor T cells in adults with B‐cell malignancies
Authors: Tuazon Sherilyn A. , Li Ang , Gooley Theodore , Eunson Thomas W. , Maloney David G. , Turtle Cameron J. , Linenberger Michael L. , Connelly‐Smith Laura S.
Published: February 2019

BACKGROUND

The clinical and procedural parameters that affect the optimal collection of lymphocytes for the production of chimeric antigen receptor (CAR) T cells remain undefined but are increasingly important, as commercial products are now available. We evaluated determinants of low lymphocyte collection efficiency (CE) and the rate of successful CAR T‐cell manufacture in middle‐aged and older adults with advanced B‐cell malignancies.

STUDY DESIGNS AND METHODS

Mononuclear cell collections using two apheresis platforms (COBE Spectra and Spectra Optia, Terumo BCT) from patients participating in a CD19‐directed CAR T‐cell therapy trial were reviewed. Patient‐ and disease‐specific factors, peripheral blood counts, apheresis parameters, and product cell counts were analyzed to determine effects on lymphocyte CE.

RESULTS

Ninety‐two apheresis events from patients with acute lymphocytic leukemia (ALL) (n = 28), chronic lymphocytic leukemia (n = 18), and non‐Hodgkin lymphoma (n = 46) were available for analysis. Forty‐one collections (45%) had a lymphocyte CE of <40%. On multivariable analysis, age (every 10‐year increase, odds ratio [OR] = 1.51; p = 0.034), disease type (chronic lymphocytic leukemia vs. ALL, OR = 0.24; p = 0.052; non‐Hodgkin lymphoma vs. ALL, OR = 0.20; p = 0.009) and precollection platelets (every 10 × 103/μL increase, OR = 1.07; p = 0.005) were appreciably associated with a lymphocyte CE of <40%. No major apheresis complications occurred.

CONCLUSIONS

Lymphocyte collection at our center was well tolerated and 100% successful in manufacturing CD19‐directed CAR T cells from adult patients with B‐cell malignancies despite low CE in some patients. A diagnosis of ALL, advancing age, and higher preapheresis platelet counts were observed to be associated with low CE.
Geometric Langlands correspondence for , over the pair of pants
Authors: Nadler David , Yun Zhiwei
Published: February 2019

We establish the geometric Langlands correspondence for rank-one groups over the projective line with three points of tame ramification.
Nonabelian Hodge theory for klt spaces and descent theorems for vector bundles
Authors: Greb Daniel , Kebekus Stefan , Peternell Thomas , Taji Behrouz
Published: February 2019

We generalise Simpson’s nonabelian Hodge correspondence to the context of projective varieties with Kawamata log terminal (klt) singularities. The proof relies on a descent theorem for numerically flat vector bundles along birational morphisms. In its simplest form, this theorem asserts that given any klt variety$X$and any resolution of singularities, any vector bundle on the resolution that appears to come from$X$numerically, does indeed come from $X$. Furthermore, and of independent interest, a new restriction theorem for semistable Higgs sheaves defined on the smooth locus of a normal, projective variety is established.
A Guiding Framework for Microextrusion Additive Manufacturing
Authors: Udofia Edidiong Nseowo , Zhou Wenchao
Published: February 2019

Although extrusion-based 3D printing processes have seen many successful applications at the macroscale, it has proven to be challenging for consistent, repeatable, and cost-effective printing at the microscale due to its dynamic complexities. To fully tap into the promise of microextrusion printing (µEP) of fabricating fine resolution features, it is critical to establish an understanding of the fundamentals of ink flow, interface energy, drying, and the process-property relationship of the printing process. To date, a comprehensive and coherent organization of this knowledge from relevant literature in different fields is still lacking. In this paper, we present a framework of the underlying principles of the microextrusion process, offering an overall roadmap to guide successful printing based on both results in the literature and our own experimental tests. The impacts of various process parameters on the resolution of printed features are identified. Experiments are carried out to validate the developed framework. Key challenges and future directions of microextrusion 3D printing are also highlighted.
The Effect of Temperature on Puncture Resistance of Glass Cloth Reinforced Polyester Composites
Authors: Ahmed Saad R. , Khanna Sanjeev
Published: February 2019

Reinforced polyester composites are widely used in many applications where puncture resistance is important. This research is aimed at understanding whether exposure to different temperatures, high and very low, affects the puncture resistance of a glass cloth reinforced polyester composite and the unreinforced polyester matrix. The temperature range investigated was +80 °C to −80 °C. A hemispherical drop-weight impactor was used for the puncture tests in an environmentally controlled chamber. The reinforced composite specimens are more puncture-resistant compared with the unreinforced polyester at all temperatures. The damage created by the impact reduces with decreasing temperatures, while the energy absorbed remains constant with temperature.
Constant-Speed Oscillation of a Pump Turbine Observed on a Pumped-Storage Model System
Authors: Hu Jinhong , Yang Jiandong , Zeng Wei , Yang Jiebin
Published: February 2019

The hydraulic characteristics of pump turbines in off-design conditions, especially the S-shaped characteristics, are crucial for the safety and stability of the unit. To explore the S-characteristics of pump turbines through a transient method, an experimental investigation was conducted based on a pumped-storage model system at Wuhan University. By shutting down the circulating pump, a special transient process was triggered, forcing the pump turbine to operate in turbine mode, turbine brake mode, and reverse rotational pump mode. As the rotational speed of the pump turbine was maintained almost constant in the oscillation process with a maximum deviation of 0.6%, this transient operation was named as constant-speed oscillation (CSO). The parameters for global performance and pressure pulsations in the vaneless gap were measured and analyzed. In addition, the one-dimensional rigid column theory was used to establish a mathematical model for simulation. The results from simulation were quantitatively compared with the experimental results. Finally, the reason for the CSO was theoretically explained based on stability analysis through the established mathematical model. It was observed that the positive slope of ned–Qed characteristic curves at no-flow resulted in this oscillation. In contrast, the simulation was performed under the same conditions with a modified ned–Qed characteristic curve, which had a negative slope at no-flow. However, the results showed that, with the modified characteristic curve, the pump turbine would stabilize at no-flow.
Preparation and Tribological Properties of Modified Field’s Alloy Nanoparticles as Additives in Liquid Poly-alfa-olefin Solution
Authors: Wang Chaoming , Zhang Xinran , Jia Wenbing , Deng Qiaoyuan , Leng Yongxiang
Published: February 2019

This study described the synthesis and the tribological properties of surface-modified Field’s alloy nanoparticles, which were prepared by a facile one-step nanoemulsion method and using ethyl carbamate as a surfactant, as additives in liquid poly-alfa-olefin (PAO) oil. The size and morphology of nanoparticles were investigated by transmission electron microscopy (TEM). The zeta potential, viscosity, and stability properties of the surface-modified nanoparticles suspended in PAO oil (called nanofluid) with different mass concentrations were measured by a viscometer and Zeta potential analyzer, respectively. The tribological properties of the nanofluid were tested by a ball to disk wear and friction machine. Compared with pure PAO oil, the results showed that the nanofluids had better lubricating behaviors. When the mass concentration of modified nanoparticles was 0.08 wt. %, both the friction coefficient and the wear scar diameter were the lowest.
Coupling Effects of Viscous Sheet and Ambient Fluid on Boundary Layer Flow and Heat Transfer in Power-Law Fluids
Authors: Liu Xiaochuan , Zheng Liancun , Chen Goong , Ma Lianxi
Published: February 2019

This paper investigates the flow and heat transfer of power-law fluids over a stretching sheet where the coupling dynamics influence of viscous sheet and ambient fluid is taken into account via the stress balance. A modified Fourier's law is introduced in which the effects of viscous dissipation are taken into account by assuming that the thermal conductivity is to be shear-dependent on the velocity gradient. The conditions for both velocity and thermal boundary layers admitting similarity solutions are found, and numerical solutions are computed by a Bvp4c program. The results show that the viscous sheet and rheological properties of ambient fluids have significantly influences on both velocity and temperature fields characteristics. The formation of sheet varies with the viscosity of fluid and draw ratio, which then strongly affects the relations of the local skin friction coefficient, the local Nusselt number, and the generalized Reynolds number. Moreover, for specified parameters, the flow and heat transfer behaviors are discussed in detail.
In Situ Additive Manufacturing Process Monitoring With an Acoustic Technique: Clustering Performance Evaluation Using K-Means Algorithm
Authors: Taheri Hossein , Koester Lucas W. , Bigelow Timothy A. , Faierson Eric J. , Bond Leonard J.
Published: February 2019

Additive manufacturing (AM) is based on layer-by-layer addition of materials. It gives design flexibility and potential to decrease costs and manufacturing lead time. Because the AM process involves incremental deposition of materials, it provides unique opportunities to investigate the material quality as it is deposited. Development of in situ monitoring methodologies is a vital part of the assessment of process performance and understanding of defects formation. In situ process monitoring provides the capability for early detection of process faults and defects. Due to the sensitivity of AM processes to different factors such as laser and material properties, any changes in aspects of the process can potentially have an impact on the part quality. As a result, in-process monitoring of AM is crucial to assure the quality, integrity, and safety of AM parts. There are various sensors and techniques that have been used for in situ process monitoring. In this work, acoustic signatures were used for in situ monitoring of the metal direct energy deposition (DED) AM process operating under different process conditions. Correlations were demonstrated between metrics and various process conditions. Demonstrated correlation between the acoustic signatures and the manufacturing process conditions shows the capability of acoustic technique for in situ monitoring of the additive manufacturing process. To identify the different process conditions, a new approach of K-means statistical clustering algorithm is used for the classification of different process conditions, and quantitative evaluation of the classification performance in terms of cohesion and isolation of the clusters. The identified acoustic signatures, quantitative clustering approach, and the achieved classification efficiency demonstrate potential for use in in situ acoustic monitoring and quality control for the additive manufacturing process.
Reliability-Based Design Optimization of Surface-to-Surface Contact for Cutting Tool Interface Designs
Authors: Camuz Soner , Bengtsson Magnus , Söderberg Rikard , Wärmefjord Kristina
Published: February 2019

In recent years, cutting tool manufacturers are moving toward improving the robustness of the positioning of an insert in the tool body interface. Increasing the robustness of the interface involves designs with both chamfered and serrated surfaces. These designs have a tendency to overdetermine the positioning and cause instabilities in the interface. Cutting forces generated from the machining process will also plastically deform the interface, consequently, altering the positioning of the insert. Current methodologies within positioning and variation simulation use point-based contacts and assume linear material behavior. In this paper, a first-order reliability-based design optimization framework that allows robust positioning of surface-to-surface-based contacts is presented. Results show that the contact variation over the interface can be limited to predefined contact zones, consequently allowing successful positioning of inserts in early design phases of cutting tool designs.
Rules-of-thumb to design a uniform spherical array for direction finding—Its Cramér–Rao bounds' nonlinear dependence on the number of sensors
Authors: Wong Kainam Thomas , Morris Zakayo Ndiku , Nnonyelu Chibuzo Joseph
Published: February 2019

This paper discovers rules-of-thumb on how the estimation precision for an incident source's azimuth-polar direction-of-arrival (ϕ,θ) depends on the number (L) of identical isotropic sensors spaced uniformly on an open sphere of radius R. This estimation's corresponding Cramér–Rao bounds (CRB) are found to follow these elegantly simple approximations, useful for array design: (i) For the azimuth arrival angle: 2π(R/λ)(σs/σn)2LMCRB(ϕ) sin(θ)≈(Le1/14)−1+3→L→∞3, ∀(ϕ,θ); and (ii) for the polar arrival angle: 2π(R/λ)(σs/σn)2LMCRB(θ)≈3−(Le6/7)−1→L→∞3, ∀(ϕ,θ). Here, M denotes the number of snapshots, λ refers to the incident signal's wavelength, and (σs/σn)2 symbolizes the signal-to-noise power ratio.
Modulation of the sigma-1 receptor–IRE1 pathway is beneficial in preclinical models of inflammation and sepsis
Authors: Rosen Dorian A. , Seki Scott M. , Fernández-Castañeda Anthony , Beiter Rebecca M. , Eccles Jacob D. , Woodfolk Judith A. , Gaultier Alban
Published: February 2019

Sigma-1 receptor is a critical inhibitor of endoplasmic reticulum–driven inflammation and a potential therapeutic target in septic shock.
Transforming lung to treat type 1 diabetes
Authors: Shen Keyue
Published: February 2019

A tissue engineering strategy repurposes lung tissue for islet transplantation.
Circulation of Plasmids Harboring Resistance Genes to Quinolones and/or Extended-Spectrum Cephalosporins in Multiple
Salmonella enterica
Serotypes from Swine in the United States
Authors: Elnekave Ehud , Hong Samuel L. , Lim Seunghyun , Hayer Shivdeep S. , Boxrud Dave , Taylor Angela J. , Lappi Victoria , Noyes Noelle , Johnson Timothy J. , Rovira Albert , Davies Peter , Perez Andres , Alvarez Julio
Published: February 2019

Nontyphoidal
Salmonella enterica
(NTS) poses a major public health risk worldwide that is amplified by the existence of antimicrobial-resistant strains, especially those resistant to quinolones and extended-spectrum cephalosporins (ESC). Little is known on the dissemination of plasmids harboring the acquired genetic determinants that confer resistance to these antimicrobials across NTS serotypes from livestock in the United States.
The Algicidal Bacterium
Kordia algicida
Shapes a Natural Plankton Community
Authors: Bigalke Arite , Meyer Nils , Papanikolopoulou Lydia Alkistis , Wiltshire Karen Helen , Pohnert Georg
Published: February 2019

Plankton communities change on a seasonal basis in temperate systems, with distinct succession patterns; this is mainly due to algal species that have their optimal timing relative to environmental conditions. We know that bacterial populations are also instrumental in the decay and termination of phytoplankton blooms. Here, we describe algicidal bacteria as modulators of this important species succession. Upon treatment of a natural plankton consortium with an algicidal bacterium, we observed a strong shift in the phytoplankton community structure, compared to controls, resulting in formation of a succeeding
Phaeocystis
bloom. Blooms of this alga have a substantial impact on global biogeochemical and ecological cycles, as they are responsible for a substantial proportion of primary production during spring in the North Sea. We propose that one of the key factors influencing such community shifts may be algicidal bacteria.
Detection of Natural Products and Their Producers in Ocean Sediments
Authors: Tuttle Robert N. , Demko Alyssa M. , Patin Nastassia V. , Kapono Clifford A. , Donia Mohamed S. , Dorrestein Pieter , Jensen Paul R.
Published: February 2019

Natural products are readily isolated from cultured bacteria and exploited for useful purposes, including drug discovery. However, these compounds are rarely detected in the environments from which the bacteria are obtained, thus limiting our understanding of their ecological significance. Here, we used environmental metabolomics to directly assess chemical diversity in marine sediments. We identified numerous metabolites and, in one case, isolated strains of bacteria capable of producing one of the compounds detected. Coupling environmental metabolomics with community and metagenomic analyses provides opportunities to link compounds and producers and begin to assess the complex interactions mediated by specialized metabolites in marine sediments.
Characterizing the Key Agents in a Disease-Suppressed Soil Managed by Reductive Soil Disinfestation
Authors: Liu Liangliang , Huang Xinqi , Zhao Jun , Zhang Jinbo , Cai Zucong
Published: February 2019

Most defined systems have identified microbial elements as the primary factors determining disease suppression, but the involvement of the soil abiotic environment is less defined. The significance of this work is that the soil abiotic environment plays a critical role in the establishment of the soil microbial community and key microbial agents that directly contribute to the prevention of soilborne diseases. We highlight the importance of the soil abiotic environment in disease suppression. Furthermore, we provide a framework for the characterization of disease-suppressing agents in artificially managed soil. These results will gradually close the gap in knowledge on soil environment-microbe interactions.
Porcine Gastric Mucin Triggers Toxin Production of Enteropathogenic
Bacillus cereus
Authors: Jessberger Nadja , Dietrich Richard , Mohr Ann-Katrin , Da Riol Claudia , Märtlbauer Erwin
Published: February 2019

Enteropathogenic
Bacillus cereus
causes foodborne infections due to the production of pore-forming enterotoxins in the intestine. Before that, spores have to be ingested, survive the stomach passage, and germinate.
Arterial thrombosis as primary presentation of endogenous Cushing’s syndrome
Authors: Alexander Vijay , Koshy Maria , Dasgupta Riddhi , Carey Ronald Albert
Published: February 2019

Cushing’s syndrome is known to present with a characteristic set of clinical manifestations and complications, well described in literature. However, hypercoagulability remains an under recognised entity in Cushing’s syndrome. A 31-year-old woman from Southern India presented with history of fever, left upper quadrant pain and progressive breathing difficulty for 3 weeks. Clinical examination revealed discriminatory features of Cushing’s syndrome. Laboratory investigations showed biochemical features of endogenous ACTH-dependent Cushing’s syndrome. Imaging of the abdomen revealed splenic collection, left-sided empyema and extensive arterial thrombosis. Gadolinium enhanced dynamic MRI of the pituitary gland revealed no evidence of an adenoma while a Ga-68 DOTATATE positron emission tomography CT scan ruled out an ectopic Cushing’s. A diagnosis of endogenous Cushing’s syndrome causing a prothrombotic state with extensive arterial thrombosis was made. She was initiated on oral anticoagulation and oral ketoconazole for medical adrenal suppression. She subsequently underwent bilateral adrenalectomy and was well at follow-up.
High tibial osteotomy in combination with arthroscopic abrasion arthroplasty and autologous adipose-derived mesenchymal stem cell therapy in the treatment of advanced knee osteoarthritis
Authors: Freitag Julien , Norsworthy Cameron , Wickham James , Shah Kiran , Tenen Abi
Published: February 2019

Osteoarthritis is a progressive and debilitating condition. An increasing number of total knee replacements are being performed under the age of 65. Improved understanding of the action of mesenchymal stem cells (MSC) has seen renewed interest in their role in cartilage repair. A 43-year-old man presented with grade IV medial compartment knee osteoarthritis. The patient underwent high tibial osteotomy (HTO) and arthroscopic abrasion arthroplasty in combination with adipose-derived MSC therapy. The patient reported improvement in pain and function as measured by validated outcome scores. Repeat MRI including T2 mapping techniques showed hyaline-like cartilage regeneration. This case highlights the potential benefit of surgical interventions including HTO in combination with MSC therapy in early-onset severe osteoarthritis. This technique may considerably delay or prevent the need for total knee replacement in young patients. Further controlled trials are needed to confirm the reproducibility of this outcome.
Application of multistate modeling to estimate salmonid survival and movement in relation to spatial and temporal variation in metal exposure in a mining-impacted river
Authors: Mayfield Mariah P. , McMahon Thomas E. , Rotella Jay J. , Gresswell Robert E. , Selch Trevor , Saffel Patrick , Lindstrom Jason , Liermann Bradley
Published: February 2019

Multistate modeling was used to estimate survival and movement of brown trout (Salmo trutta) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) in relation to copper concentrations in the mining-impacted Clark Fork River, Montana. Survival probability in the uppermost river segment, where dissolved copper concentrations frequently exceeded acute criteria for aquatic life (range: 31–60 days > 13.4 μg·L–1), was 2.1 times lower for brown trout and 122 times lower for westslope cutthroat trout compared with survival rates in the lowermost segment that had relatively low dissolved copper (0 days exceedance of acute concentration). Lowest survival for both species occurred in the spring–summer period when dissolved copper concentrations were elevated coincident with higher discharge. Movement among study segments was generally low, and cutthroat trout showed low movement into the uppermost river segment with the most elevated copper levels. Both species showed high rates of movement into tributaries, which coincided with their respective spawning migrations rather than as an apparent avoidance of elevated copper levels. The linkage between survival rate and level of copper exposure for both trout species suggests that additional removal of tailings deposits could improve survival rates.