bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlation of fetal blood vessel Doppler measurements with fetal anemia among Rhesus isoimmunized pregnancies after two intrauterine transfusions
Authors: Kumari Sarita , Deka Dipika , Dadhwal Vatsla , Perumal Vanamail
Published: April 2019

Objective

To assess the correlation between fetal blood vessel Doppler measurements and fetal anemia among Rhesus isoimmunized pregnancies after two intrauterine transfusions as a potential guide to therapy.

Methods

A prospective observational study was conducted among 30 women who attended a single hospital in India between April 2, 2015 and October 30, 2016. The participants underwent a third intrauterine transfusion based on a middle cerebral artery (MCA) peak systolic velocity (PSV) of greater than 1.50 multiples of the median (MoM). Cordocentesis was performed before the third intrauterine transfusion and hematocrit values correlated with the blood vessel Doppler measurements.

Results

The MCA PSV MoM and fetal hematocrit MoM had a correlation coefficient of −0.43 (95% confidence interval −0.68 to 0.08; P=0.017). The sensitivity, specificity, positive predictive value, and negative predictive value were 68%, 57%, 83%, and 33%, respectively. The descending aorta PSV δ and fetal hematocrit δ had a correlation coefficient of −0.54 (95% confidence interval −0.75 to −0.23; P=0.001). An area under the curve of 0.80 (standard error 0.085; P=0.017) had 87% sensitivity and 57% specificity for diagnosing fetal anemia.

Conclusion

The descending aorta PSV could offer a useful diagnostic adjunct to MCA PSV after two intrauterine transfusions.
Changes in fetal membrane histology with cervical insufficiency and transabdominal cerclage
Authors: Steenhaut Patricia , Depoix Christophe , Hubinont Corinne , Debiève Frédéric
Published: April 2019

Objective

To determine whether term fetal membranes from transabdominal cerclage (TAC) patients have favorable characteristics compared with membranes from patients without TAC.

Methods

A prospective study of consecutive pregnant women who had undergone TAC and were delivered by elective cesarean after 37 weeks before the onset of labor at Cliniques universitaires Saint‐Luc, Brussels, between January 2015 and June 2016. Membranes were collected from two areas: overlying the cervix and located far from the cervix. Membrane thickness, 15‐hydroxyprostaglandin dehydrogenase (PGDH), toll‐like receptor‐2 (TLR2) expression, and senescence were measured and compared between the TAC group and a control group without TAC enrolled using the same study criteria.

Results

In the cervical area of the TAC group, the chorion was significantly thicker (P=0.003). PGDH and TLR2 expression were also significantly increased in the cervical area of the TAC group (P=0.021 and P=0.043, respectively). Senescence was significantly decreased in the TAC group (P=0.001).

Conclusion

A significant relationship between chorion thickening and increase in PGDH and TLR2 expression and decrease in senescence was reported in the cervical area of membranes in the TAC group. These membrane changes could prevent triggering of parturition and may account for favorable outcomes and clinical success in pregnancies with TAC.
Toward the development of a short multi‐country person‐centered maternity care scale
Authors: Afulani Patience A. , Feeser Karla , Sudhinaraset May , Aborigo Raymond , Montagu Dominic , Chakraborty Nirali
Published: April 2019

Objective

To develop a shortened, valid and reliable scale applicable across multiple settings for routine monitoring of person‐centered maternity care (PCMC).

Methods

Exploratory analysis was used to generate parsimonious versions of a 30‐item PCMC scale in four datasets from cross‐sectional surveys conducted between August 2016 and October 2017, involving women aged 15–49 years in Kenya, Ghana and India who had recently given birth. Analysis was informed by expert opinion via a separate online survey of global maternal and child health experts. Items retained in each dataset were compared, and those unique to a single setting removed. The remaining items were pooled and assessed for construct and criterion validity and reliability in each setting.

Results

Thirteen items were retained for a potential multi‐setting short PCMC scale, incorporating the domains of dignity and respect, communication and autonomy, and supportive care. Cronbach's alpha for the scale was >0.7 in each setting. Scores on the 13‐item scale were correlated with the 30‐item scale scores, and with global measures of care satisfaction in Kenya and India.

Conclusion

Analysis yielded a 47% shorter PCMC scale, that showed promise for routine assessment of women's experience of care during childbirth across multiple settings. However, further validation is needed.
The role of inflammation, oxidative stress, angiogenesis, and apoptosis in the pathophysiology of endometriosis: Basic science and new insights based on gene expression
Authors: Samimi Mansooreh , Pourhanifeh Mohammad Hossein , Mehdizadehkashi Abolfazl , Eftekhar Tahereh , Asemi Zatollah
Published: April 2019

Endometriosis is a frequent and chronic illness in young women which could be defined by the existence of endometrial stroma and glands outside of the normal site of the lining of the uterus. It has painful symptoms. The advanced stage of endometriosis may lead to gynecological malignancies, such as ovarian cancer, and other complications, including infertility. However, its exact physiopathology is not well known. Recent studies have shown the possible roles of inflammation along with oxidative stress. Additionally, angiogenesis and apoptosis dysregulation contribute to endometriosis pathophysiology. Therapeutic strategies and continuing attempts, to conquer endometriosis should be done regarding molecular signaling pathways. Thus, the present review summarizes current studies and focuses on molecular mechanisms.
Retracted: 9za plays cytotoxic and proapoptotic roles and induces cytoprotective autophagy through the PDK1/Akt/mTOR axis in non‐small‐cell lung cancer
Authors: Liu Rangru , Chen Zhuo , Yi Xinan , Huang Fengying , Hu Gaoyun , Liu Danqi , Li Xi , Zhou Honghao , Liu Zhaoqian
Published: April 2019

Non‐small‐cell lung cancer (NSCLC) is an aggressive subtype of pulmonary carcinomas with high mortality. However, chemotherapy drug resistance and high recurrence rates hinder the curative effect of platinum‐based first‐line chemotherapy, which makes it urgent to develop new antitumor drugs for NSCLC. 9za, a new candidate drug synthesized by our research group, has been verified with potent antilung cancer activity in preliminary experiments. However, the underlying molecular mechanism of 9za remains largely vague. This work revealed that 9za could play important cytotoxic and proapoptotic roles in NSCLC cells. Moreover, 9za could induce autophagy and promote autophagy flux. Interestingly, the cytotoxic and proapoptotic roles were significantly dependent on 9za‐induced cytoprotective autophagy. That is, the coadministration of 9za with an autophagy inhibitor such as chloroquine or 3‐methyladenine exhibited increased cytotoxic and proapoptotic effects compared with 9za treatment alone. In addition, 9za exposure suppressed the phosphorylation of phosphoinositide‐dependent protein kinase 1 (PDK1), protein kinase B (Akt), mammalian targets of rapamycin (mTOR), p70 S6 kinase, and 4E binding protein 1 by a dose‐dependent way, manifesting that the Akt/mTOR axis was implicated in 9za‐induced autophagy. In addition, the overexpression of PDK1 resulted in increased phosphorylation of PDK1 and Akt and blocking of 9za‐mediated autophagy. These data showed that the PDK1/Akt/mTOR pathway was involved in 9za‐induced autophagy. Hence, this work provides a theoretical basis for exploiting 9za as a new antilung cancer candidate drug and hints that the combination of 9za with an autophagy inhibitor is a feasible alternative approach for the therapy of NSCLC.
N‐myc downstream‐regulated gene 2 controls astrocyte morphology via Rho‐GTPase signaling
Authors: Zhang Zengli , Ma Zhi , Zou Wangyuan , Zhang Lixia , Li Yan , Zhang Jian , Liu Min , Hou Wugang , Ma Yulong
Published: April 2019

Astrocyte undergoes morphology changes that are closely associated with the signaling communications at synapses. N‐myc downstream‐regulated gene 2 (NDRG2) is specifically expressed in astrocytes and is associated with several important astrocyte functions, but its potential role(s) relating to astrocyte morphological changes remain unknown. Here, primary astrocytes were prepared from neonatal Ndrg2+/+ and Ndrg2−/− pups, and the drug Y27632 was used to induce stellation. We then used a variety of methods to measure the levels of NDRG2, α‐Actinin4, and glial fibrillary acidic protein (GFAP), and the activity of RhoA, Rac1, and Cdc42 in Y27632‐treated astrocytes as well as in Ndrg2+/+, Ndrg2−/−, or Ndrg2−/− + lentivirus (restore NDRG2 expression) astrocytes. We also conducted live‐imaging and proteomics studies of the cultured astrocytes. We found that induction of astrocytes stellation (characterized by cytoplasmic retraction and process outgrowth) resulted in increased NDRG2 protein expression and Rac1 activity and in reduced α‐Actinin4 protein expression and RhoA activity. Ndrg2 deletion induced astrocyte flattening, whereas the restoration of NDRG2 expression induced stellation. Ndrg2 deletion also significantly increased α‐Actinin4 protein expression and RhoA activity yet reduced GFAP protein expression and Rac1 activity, and these trends were reversed by restoration of NDRG2 expression. Collectively, our results showed that Ndrg2 deletion promoted cell proliferation, interrupted stellation capability, and extensively altered the protein expression profiles of proteins that function in Rho‐GTPase signaling. These findings suggest that NDRG2 functions to regulate astrocytes morphology via altering the accumulation of the Rho‐GTPase signaling pathway components, thereby supporting that NDRG2 should be understood as a regulator of synaptic plasticity and thus neuronal communications.
Variety‐Seeking and Perceived Expertise
Authors: Sela Aner , Hadar Liat , Morgan Siân , Maimaran Michal
Published: April 2019

People often infer expertise from the choice of unique, rare, or sophisticated options. But might mere variety‐seeking also serve as a signal of expertise, and if so, how? Six studies show that the relationship between variety‐seeking and perceived expertise is not unidirectional and depends on the perceiver's own level of expertise. Category experts perceive lower variety‐seeking as indicative of discernment, which in turn increases perceived expertise in that category. Consequently, experts choose less variety to portray themselves as experts. In contrast, novices perceive high variety‐seeking as indicative of category breadth knowledge, which in turn increases their perception of category expertise. Consequently, novices choose more variety to portray themselves as experts. The findings make novel theoretical contributions to research on variety‐seeking, consumer expertise, and social perception, as well as practical contributions for marketers of product assortments and bundles.
Seasonal changes in the song control nuclei of the Rufous‐bellied Thrush, Turdus rufiventris (Oscine, Passeriformes, and Turdidae)
Authors: Lorena Jamily , Olson Christopher R. , Fontana Carla S. , Mello Claudio V. , Schneider Maria Paula C. , Schneider Patricia N.
Published: April 2019

In vocal learning birds, memorization and song production rely on a set of telencephalic nuclei referred to as the song control system. Seasonal changes in song production are correlated with changes in the volume of the song control nuclei and are influenced by photoperiodic conditions and hormonal cues. The seasonal volume changes in the avian brain that controls singing are thought to involve regulation of neuronal replacement, which is a striking example of neuronal plasticity. The Rufous‐bellied Thrush (Turdus rufiventris) is a seasonally breeding bird that actively sings during the spring and summer (breeding season) and is relatively silent in the fall, yet possible mechanisms behind the periodic changes in song production remain unknown. Here, we have examined two song control nuclei: High vocal center (HVC) and robust nucleus of arcopallium (RA) in fall males, spring males, and fall females of Rufous‐bellied Thrush. The cytoarchitectonic organization was analyzed and quantified from Nissl‐stained sections, and gene expression of song nuclei markers was examined by in situ hybridization during breeding and nonbreeding seasons. We observed a reduction in HVC volume and reductions in parvalbumin, and RGS4 expression in HVC and RA in males during the nonbreeding season. These findings provide evidence of seasonal changes in the song system of a representative tropical‐breeding Turdidae species that does not maintain territories or mate bonding, setting the histological and molecular groundwork for future studies aimed at better understanding of song nuclei changes in seasonally breeding songbirds.
On quasi‐infinitely divisible distributions with a point mass
Authors: Berger David
Published: April 2019

An infinitely divisible distribution on is a probability measure μ such that the characteristic function has a Lévy–Khintchine representation with characteristic triplet , where ν is a Lévy measure, and . A natural extension of such distributions are quasi‐infinitely distributions. Instead of a Lévy measure, we assume that ν is a “signed Lévy measure”, for further information on the definition see [10]. We show that a distribution with and , where is the absolutely continuous part, is quasi‐infinitely divisible if and only if for every . We apply this to show that certain variance mixtures of mean zero normal distributions are quasi‐infinitely divisible distributions, and we give an example of a quasi‐infinitely divisible distribution that is not continuous but has infinite quasi‐Lévy measure. Furthermore, it is shown that replacing the signed Lévy measure by a seemingly more general complex Lévy measure does not lead to new distributions. Last but not least it is proven that the class of quasi‐infinitely divisible distributions is not open, but path‐connected in the space of probability measures with the Prokhorov metric.
Impact of noise reduction schemes on quantitative accuracy of CT numbers
Authors: Cruz‐Bastida Juan P. , Zhang Ran , Gomez‐Cardona Daniel , Hayes John , Li Ke , Chen Guang‐Hong
Published: April 2019

Purpose

In previous works, it has been demonstrated that for filtered backprojection (FBP) reconstruction‐based computed tomography (CT) images, the measured CT numbers are biased and the bias level decreases with increasing radiation dose. Low‐dose scans typically include noise reduction schemes to reduce noise level. The purpose of this work was to investigate the potential impact of different noise reduction schemes on the CT number bias.

Methods

Three different filtration methods: Gaussian, adaptive trimmed mean (ATM), and anisotropic diffusion (AD) were implemented to reduce noise. All filters were independently applied in three different domains: raw counts, log‐processed sinogram, or reconstructed image domain. A quality assurance phantom was scanned on a benchtop CT cone beam CT system, at dose levels ranging from 0.6 to 4.0 mGy. The conventional FBP reconstructions were performed to reconstruct CT images for the study of CT number biases. The CT number bias of different material inserts in the phantom was then measured. To further study the overall impact of CT number bias together with the potential consequences of noise reduction schemes on both the spatial resolution and noise characteristics, the task‐based detectability of a high‐contrast and high spatial resolution imaging task was used as an example to assess the performance of each noise reduction scheme. To qualitatively assess the impact of these noise reduction schemes on image, an anthropomorphic head phantom was also scanned on the benchtop CT system and processed with the above noise reduction schemes to generate images for demonstration.

Results

Our results demonstrated the following major findings: (a) CT number bias can be significantly reduced when the noise reduction schemes are implemented in the raw counts domain; CT number bias cannot be reduced when these noise reduction schemes are implemented either in the reconstructed image domain or in the log‐processed sinogram domain. (b) The extent of CT number bias reduction is dependent on both the material composition and noise reduction parameters. (c) The overall impact of the noise reduction schemes can be studied using the task‐based detectability analysis framework and this framework can be used to select the appropriate parameters in each noise reduction scheme to optimize the performance for a given imaging task.

Conclusions

Noise reduction schemes can be used to considerably reduce CT number bias when they are implemented in the raw counts domain; however, their application cannot be arbitrarily extended to either the log‐processed sinogram data domain or image domain. Trade‐offs between bias reduction and overall image quality must be studied for an optimal performance of a given imaging task.
Motor function performance in individuals with RYR1‐related myopathies
Authors: Witherspoon Jessica W. , Vuillerot Carole , Vasavada Ruhi P. , Waite Melissa R. , Shelton Monique , Chrismer Irene C. , Jain Minal S. , Meilleur Katherine G.
Published: April 2019

Introduction

The objective of this study was to obtain a 6‐month natural history of motor function performance in individuals with RYR1‐ related myopathy (RYR1‐RM) by using the Motor Function Measure‐32 (MFM‐32) and graded functional tests (GFT) while facilitating preparation for interventional trials.

Methods

In total, 34 participants completed the MFM‐32 and GFTs at baseline and 6‐month visits.

Results

Motor deficits according to MFM‐32 were primarily observed in the standing and transfers domain (D1; mean 71%). Among the GFTs, participants required the most time to ascend/descend stairs (>7.5 s). Functional movement, determined by GFT grades, was strongly correlated with MFM‐32 (D1; r ≥ 0.770, P < 0.001). Motor Function Measure‐32 and GFT scores did not reflect any change in performance between baseline and 6‐month visits.

Discussion

The MFM‐32 and GFTs detected motor impairment in RYR1‐RM, which remained stable over 6 months. Thus, these measures may be suitable for assessing change in motor function in response to therapeutic intervention. Muscle Nerve 60: 80–87, 2019
Evaluation of Portable Water Filtration Systems to Reduce the Transport Risk of Zebra Mussels and Asian Clams during Fish Spawning and Trap-and-Transfer Operations
Authors: Schall Benjamin J
Published: April 2019

Invasive species represent a substantial threat to aquatic systems, and aquaculture operations provide a vector for their transportation between waters. Moving large volumes of water during fish spawning or trap-and-transfer operations increases the risk of transporting invasive bivalve larvae, particularly from sources experiencing nondetection error. This study evaluated the effectiveness of two portable filter systems at reducing or eliminating zebra mussel Dreissena polymorpha and Asian clam Corbicula fluminea veligers from an infested water source. A small setup was assessed at intervals to 1,420 L using combinations of 20- and 5-μm filters arranged in tandem, whereas a large setup was tested at intervals to 7,041 L with combinations of 30- and 5-μm tandem filters operating at two pressure ranges. Zero veligers were observed in 36 small-setup filtered water samples. Four zebra mussel veligers and zero Asian clam veligers were observed in 60 large-setup samples. Total zebra mussel and Asian clam counts from 31 unfiltered control samples were 27,846 and 1,095, respectively. Overall, both filter systems were highly effective at removing zebra mussel and Asian clam veligers and represent simple, cost-effective safeguards against nondetection error of aquatic invasive species in waters used for aquaculture practices.
Metabolic Determinants of Weight Gain in Humans
Authors: Piaggi Paolo
Published: April 2019

One of the fundamental challenges in obesity research is to identify subjects prone to weight gain so that obesity and its comorbidities can be promptly prevented or treated. The principles of thermodynamics as applied to human body energetics demonstrate that susceptibility to weight gain varies among individuals as a result of interindividual differences in energy expenditure and energy intake, two factors that counterbalance one another and determine daily energy balance and, ultimately, body weight change. This review focuses on the variability among individuals in human metabolism that determines weight change. Conflicting results have been reported about the role of interindividual differences in energy metabolism during energy balance in relation to future weight change. However, recent studies have shown that metabolic responses to acute, short‐term dietary interventions that create energy imbalance, such as low‐protein overfeeding or fasting for 24 hours, may reveal the underlying metabolic phenotype that determines the degree of resistance to diet‐induced weight loss or the propensity to spontaneous weight gain over time. Metabolically “thrifty” individuals, characterized by a predilection for saving energy in settings of undernutrition and dietary protein restriction, display a minimal increase in plasma fibroblast growth factor 21 concentrations in response to a low‐protein overfeeding diet and tend to gain more weight over time compared with metabolically “spendthrift” individuals. Similarly, interindividual variability in the causal relationship between energy expenditure and energy intake (“energy sensing”) and in the metabolic response to cold exposure (e.g., brown adipose tissue activation) seems, to some extent, to be indicative of individual propensity to weight gain. Thus, an increased understanding and the clinical characterization of phenotypic differences in energy metabolism among individuals (metabolic profile) may lead to new strategies to prevent weight gain or improve weight‐loss interventions by targeted therapies on the basis of metabolic phenotype and susceptibility to obesity in individual persons.
Physiological Predictors of Weight Regain at 1‐Year Follow‐Up in Weight‐Reduced Adults with Obesity
Authors: Nymo Siren , Coutinho Silvia R. , Rehfeld Jens F. , Truby Helen , Kulseng Bård , Martins Catia
Published: April 2019

Objective

This study aimed to assess whether changes in resting metabolic rate (RMR), exercise‐induced energy expenditure (EIEE), and appetite following weight loss (WL) are associated with weight regain at 1 year.

Methods

Thirty‐six adults with obesity underwent 8 weeks of a very‐low‐energy diet, followed by 4 weeks of refeeding and a 1‐year maintenance program. RMR, EIEE, appetite ratings, and active ghrelin, peptide YY, glucagon‐like peptide‐1, cholecystokinin, and insulin concentrations were measured at baseline, week 13, and 1 year.

Results

A 17% WL (−20 ± 5 kg [mean ± SD]; range: −11.7 to −32.2 kg; P < 0.001) was achieved at week 13. After 1 year, weight regain was 2.5 ± 9.0 kg (not significant), ranging from −18.2 to 22.5 kg. Both fat mass and fat‐free mass were reduced at week 13 (−17.9 ± 4.8 and −2.9 ± 2.7 kg, respectively; P < 0.001), while only loss of fat mass was sustained at 1 year. WL was associated with reduced RMR, EIEE, and fasting/postprandial insulin (all P < 0.001), as well as increased fasting hunger (P < 0.01) and fasting/postprandial active ghrelin (P < 0.001). There were no significant correlations between changes in RMR, EIEE, or appetite with WL and weight regain at 1 year.

Conclusions

No clear evidence emerged that changes in RMR, EIEE, or appetite following WL can predict weight regain at 1 year, but larger studies are needed to confirm these results.
Effects of liquid crystal polymer and organoclay addition on the physical properties of high‐density polyethylene films
Authors: Durmus Ali , Ercan Nevra , Alanalp Mine Begum , Gökkurt Tolga , Aydin Ismail
Published: April 2019

In this study, physical properties of high‐density polyethylene (HDPE) films, blended and reinforced with small amounts of liquid crystal polymer (LCP) and organoclay (org‐clay), were investigated by employing different characterization tools such as X‐ray diffractometer, scanning electron microscope, differential scanning calorimetry, rotational rheometer, dynamic mechanical analysis, and gas permeability measurements. Viscoelastic properties of samples were quantified by applying several test procedures in melt and solid‐state dynamic measurements. It was found that rigid LCP droplets were dispersed well into HDPE matrix and improved the melt elasticity and creep resistance of HDPE. Compatibilizer and org‐clay loading into HDPE/LCP blends yielded formation of smaller LCP droplets and reduced mean relaxation time and shear modulus values, compared to unloaded counterparts. It was observed that org‐clay stacks were dispersed into HDPE phase due to using of maleic anhydride grafted polyethylene as compatibilizer and HDPE/LCP/org‐clay ternary nanocomposites exhibited intercalated microstructure. Solid‐state uniaxial tensile creep behaviors of films were modeled with the Findley power‐law and four‐element Burger models. HDPE/LCP/org‐clay (90/10/5) ternary nanocomposite film exhibited better gas barrier performance than HDPE by decreasing its permeability by 50%. POLYM. ENG. SCI., 59:1344–1353 2019. © 2019 Society of Plastics Engineers
Wheezing independently predicts viral infection in children with community‐acquired pneumonia
Authors: Nascimento‐Carvalho Amanda C. , Ruuskanen Olli , Nascimento‐Carvalho Cristiana M.
Published: April 2019

Aim

To assess whether there was a difference in the frequency of symptoms and signs among children with community‐acquired pneumonia (CAP) with viral or bacterial infection.

Methods

A prospective cross‐sectional study was conducted in Salvador, Brazil. Children less than 5‐years‐old hospitalized with CAP were recruited. Viral or only bacterial infection was diagnosed by an investigation of 11 viruses and 8 bacteria. Bacterial infection was diagnosed by blood culture, detection of pneumococcal DNA in acute buffy coat, and serological tests. Viral infection was diagnosed by detection of respiratory virus in nasopharyngeal aspirate and serological tests. Viral infection comprised only viral or mixed viral‐bacterial infection subgroups.

Results

One hundred and eighty‐eight patients had a probable etiology established as only viral (51.6%), mixed viral‐bacterial (30.9%), and only bacterial infection (17.5%). Asthma was registered for 21.4%. Report of wheezing (47.4% vs 21.2%; P = 0.006), rhonchi (38.0% vs 15.2%;
P = 0.01), and wheezing detected on physical examination (51.0% vs 9.1%;
P < 0.001) were the differences found. Among children with asthma, detected wheezing was the only different finding when children with viral infection were compared with those with only bacterial infection (75.0% vs 0%;
P = 0.008). By multivariable analysis, viral infection (AdjOR [95% CI]: 9.6; 95%CI: 2.7‐34.0), asthma (AdjOR [95% CI]: 4.6; 95%CI: 1.9‐11.0), and age (AdjOR [95% CI]: 0.95; 95%CI: 0.92‐0.97) were independently associated with wheezing on physical examination. The positive predictive value of detected wheezing for viral infection was 96.3% (95% CI: 90.4‐99.1%).

Conclusion

Wheezing detected on physical examination is an independent predictor of viral infection.
Lung clearance index for early detection of pulmonary complications after allo‐HSCT in children
Authors: Uhlving Hilde H. , Skov Linnea , Buchvald Frederik , Heilmann Carsten , Grell Kathrine , Ifversen Marianne , Green Kent , Müller Klaus , Nielsen Kim G.
Published: April 2019

Background

Pulmonary chronic graft‐vs‐host disease (cGvHD) after hematopoietic stem cell transplantation (HSCT) is characterized by impairment of the small airways. Assessment of lung clearance index (LCI) gained from multiple breath washout (MBW) is more sensitive than spirometry in detection of small airways disease. The aim of this study was to describe the development of LCI during the first year after pediatric HSCT and how LCI relates to other pulmonary function parameters and cGvHD.

Methods

This prospective, longitudinal study included 28 pediatric HSCT‐recipients. Spirometry, Sulfur hexafluoride MBW and diffusion capacity of the lungs were performed before and at 3, 6, 9, and 12 months after HSCT. Respiratory symptoms and signs of cGvHD were recorded at each visit.

Results

Before HSCT, 47.8% had abnormal LCI and 12.5% had abnormal forced expiratory volume in 1 second (FEV1). Patients with persisting respiratory symptoms 12 months post‐HSCT had higher median LCI (factor 5.7, P = 0.0018) and lower FEV1 z‐scores (−1.5, P = 0.033) post‐HSCT compared to patients free of respiratory symptoms. Overall, post‐HSCT LCI values were 3.49 times higher and FEV1 was 2.31 z‐scores lower in eight patients with cGvHD in any organ system compared with patients without cGvHD (P = 0.0089 and P < 0.0001). LCI values during the first 3 months were not predictive of pulmonary cGvHD.

Conclusion

LCI is a sensitive marker for cGvHD and high LCI values were associated with persisting respiratory symptoms after 1 year. Further evaluation of MBW in early detection of HSCT‐related pulmonary complications require larger patient cohorts and closer follow‐up during the first months after HSCT.
Accident investigation challenges for process safety practitioners
Authors: Selk Stephen , Benner Ludwig
Published: April 2019

Investigations related to the process industry may be conducted for many kinds of unexpected occurrences including unintentional as well as intentional, relatively uncomplicated or very complex, with minor, serious or catastrophic consequences. Personnel in the process industries may become involved in any such kinds of investigations. Before getting involved, they should be aware of what will be expected of them, and how to prepare for and respond appropriately to those expectations. This report provides some information about those expectations and their origins, issues personnel are likely to encounter, and suggestions for coping with them. © 2019 American Institute of Chemical Engineers Process Saf Prog: e12053 2019
Preparation of (Cu,Ag)2SnS3 Thin‐Film Solar Cells by Sulfurizing Metal Precursors Featuring Various Ag Contents
Authors: Nakamura Shigeyuki , Eang Panha , Yamaguchi Toshiyuki , Seto Satoru , Akaki Yoji , Katagiri Hironori , Araki Hideaki
Published: April 2019

To enlarge the bandgap of Cu2SnS3 (CTS), Ag‐incorporating CTS thin films are successfully deposited by sulfurizing Ag‐Cu‐Sn precursors featuring various Ag contents and the constant Cu/Sn ratio of 1.75, which is the optimal value for CTS thin‐film solar cells. To control the Ag content of the films, the thickness of the Ag layers of the precursors is varied from 0 to 200 nm, which corresponds to the Ag/(Ag + Cu) ratio of the films varying from 0 to 0.32. The films featuring Ag/(Ag + Cu) ratios smaller than 0.16 are solid solutions of CTS and Ag2SnS3, that is, (Cu,Ag)2SnS3 (CATS), while the film featuring the Ag/(Ag + Cu) ratio of 0.32 appears to be a mixture of CATS and Ag‐Sn‐S related crystals, such as Ag8SnS6. The grain size and bandgap increase as the Ag/(Ag + Cu) ratio increases up to 0.16. The highest power conversion efficiency (PCE) of 3.6% is obtained for the cell featuring the Ag/(Ag + Cu) ratio of 0.08. The highest open cell voltage (VOC) for the CATS thin‐film solar cells is obtained to be 0.284 mV. However, the improvement in PCE is attributed to the increase in the short‐circuit current density and fill factor of the cell rather than the increase in VOC.
Characterization of Methylammonium Lead Iodide Thin Films Fabricated by Exposure of Lead Iodide Layers to Methylammonium Iodide Vapor in a Closed Crucible Transformation Process
Authors: Dachauer Ralph , Clemens Oliver , Lakus‐Wollny Kerstin , Mayer Thomas , Jaegermann Wolfram
Published: April 2019

In this work, the characterization of methylammonium lead iodide (MAPI) layers fabricated with a modified two‐step deposition technique under high vacuum is presented. Thereby, PbI2, deposited in an open sublimation process, is exposed to methylammonium iodide (MAI) vapor in a closed crucible. The fabricated layers are examined with scanning electron microscopy (SEM), X‐ray diffraction (XRD), UV/VIS absorption spectroscopy, and photoelectron spectroscopy (PES). In addition, planar solar cells incorporating the MAPI layers are produced. The obtained XRD data show that MAPI with high perovskite phase purity can be fabricated in a broad substrate temperature range between 75 °C and 150 °C. The SEM measurements show that with increasing substrate temperature the morphology of the MAPI layers undergoes significant changes which can be separated into three distinct processes, taking place simultaneously: formation of the perovskite by incorporation of MAI into the PbI2 grains, recrystallization of the perovskite grains, and an Ostwald ripening like growth of the recrystallized grains. By the combination of the UV/VIS and in vacuo PES data, band diagrams for PbI2, MAI, and MAPI can be drawn which appear to be independent on the substrate temperature.
Dynamics of Free and Localized Excitons in Two‐Dimensional Transition Metal Dichalcogenides
Authors: Ayari Sabrine , Jaziri Sihem
Published: April 2019

Exciton kinetics in transition‐metal dichalcogenide materials is highly dependent to the experimental conditions and the quality of the sample. This study presents a comprehensive model comprising a complete set of rate equations, which account for charge transfer among multiexcitonic channels including bright and dark excitons, trions, localized excitons, to investigate the dynamics of excitons in monolayer WSe2. The exciton dynamics involving both intra‐ and intervalley scattering is discussed. In this respect, for high quality samples, it is proved that the kinetics of excitons in darkish materials is dominated by intravalley scattering in which low‐lying optically dark exciton states constitute an important reservoir while in the case of molybdenides only intervalley scattering is efficient. For low quality samples, the dynamics of localized exciton states and negative trion in case of n‐type doping sample is studied. It is shown that localized exciton states decay on a longer time scale than the trion and free exciton, consistent with experimental findings of Wang et al. [Phys. Rev. B 2014, 90, 075413]. Finally, the dependence of the trion and localized exciton dynamics as a function of the electron density is studied. It is found that the trion and localized exciton populations strongly depend to the doping density.
Rectified Ion Transport Through 2D Nanofluidic Heterojunctions
Authors: Zhang Xiaopeng , Jia Meijuan , Wang Lili , Jia Pan , Jiang Lei , Guo Wei
Published: April 2019

Nacre‐mimetic 2D nanofluidic architectures emerge as a splendid platform for both fundamental research and practical application of the novel ionic and molecular transport phenomena on nano‐ and sub‐nanoscale. So far, it is challenging to endow the 2D nanofluidic systems with asymmetric transport properties and tunable selectivity. Herein, a heterogeneous 2D nanofluidic membrane is fabricated by sequential deposition of negatively and positively charged graphene oxide (GO) nanosheets, and the rectified salt ion transport properties therein are investigated. A simple resistance model is proposed to explain the ionic current rectification. Intriguingly, by changing the relative portion of the two oppositely charged GO parts, the membrane selectivity can be modulated from perfect cation‐selectivity to anion‐selectivity. The heterogeneous GO membrane may find potential applications for water treatment and energy conversion.
An unusual endobronchial lesion: expanding the differential diagnosis
Authors: Leonard Rachel , Schultz Charles , Hadique Sarah
Published: April 2019

Synovial sarcoma is a rare tumour, accounting for approximately 2.5–10% of all soft tissue sarcomas. In the thorax, it most often presents as a large, homogenous mass and, most commonly, is the result of extrathoracic tumour metastasis. Here, we report a case of a 73‐year‐old male who presented to the hospital after a motor vehicle collision. Chest computed tomography demonstrated a 2.0 × 2.4 cm left lower lobe pulmonary nodule with endobronchial extension and a 2.5 × 2.1 cm right‐sided kidney mass. He was eventually diagnosed with monophasic synovial sarcoma. To date, only seven other cases of primary pulmonary synovial sarcoma with endobronchial extension have been reported. A review of the cases and literature is discussed.
Vanishing of cohomology groups of random simplicial complexes
Authors: Cooley Oliver , Giudice Nicola Del , Kang Mihyun , Sprüssel Philipp
Published: April 2019

We consider k‐dimensional random simplicial complexes generated from the binomial random (k + 1)‐uniform hypergraph by taking the downward‐closure. For 1 ≤ j ≤ k − 1, we determine when all cohomology groups with coefficients in from dimension one up to j vanish and the zero‐th cohomology group is isomorphic to . This property is not deterministically monotone for this model, but nevertheless we show that it has a single sharp threshold. Moreover we prove a hitting time result, relating the vanishing of these cohomology groups to the disappearance of the last minimal obstruction. We also study the asymptotic distribution of the dimension of the j‐th cohomology group inside the critical window. As a corollary, we deduce a hitting time result for a different model of random simplicial complexes introduced by Linial and Meshulam, previously only known for dimension two.
Ninth‐grade students' perceptions of the factors that led them to major in high school science, technology, engineering, and mathematics disciplines
Authors: Caspi Avner , Gorsky Paul , Nitzani‐Hendel Rakefet , Zacharia Zacharias , Rosenfeld Sherman , Berman Shmuel , Shildhouse Bruria
Published: April 2019

On completing middle‐school (ninth grade), Israeli students must choose which discipline(s) to major in upon entering high school. This study, grounded in Expectancy‐Value Theory (EVT), identified and modeled the factors that contributed to students' academic choices from their own subjective perspectives. We collected qualitative and quantitative data from ninth graders in two urban middle‐schools (n=295) at the school year's end. We found that (a) most students cited interest and utility value as their main motivations for choosing a science, technology, engineering, and mathematics (STEM) major, expectancies were mentioned less; (b) students who chose a STEM major had statistically significant higher scores for EVT's key predictor variables (personal attributes, “subjective task value,” “expectation of success,” perceived effects of environmental factors) than their counterparts who majored in non‐STEM disciplines; (c) the positive perceptions of their peers' interest and ability in science contributed significantly to students' choice to major in STEM disciplines; and (d) no significant gender differences re academic choice were found. One highly unexpected finding emerged: Participation in advanced science programs for highly qualified students (“ability grouping with curriculum differentiation”) was by far the most significant factor in the choice to major in STEM disciplines. This finding has major implications for science education policy and practice.
Convenient Synthesis of Acyclic Amidines via Copper‐Catalyzed C(sp3)‐H Amidination
Authors: He Wei , Wu Yao , Xie Dianke , Chen Yun , Sheng Wenbing , Liu Yuan , Xu Guiming , Xiao Jiang , Liu Qiang , Guo Cancheng
Published: April 2019

A convenient synthetic approach for the synthesis of α‐oxo‐acetamidines via copper‐catalyzed C(sp3)‐H amidination has been developed. This approach allows the direct amidination of three C(sp3)‐H bonds without cyclization.Methyl ketones and primary and secondary amines are tolerant and afford the corresponding products in moderate to good yields. Furthermore, this protocol is also applicable to the synthesis of unsymmetrical α‐oxo‐acetamidines via one‐pot, multicomponent reactions (MCRs).
Design and Synthesis of Bridging Chiral p–t‐Butylcalix[4]arene Tetrahydroisoquinolines and Their Application in Henry Reaction as Chiral Organocatalysts
Authors: Ma Hao , He Yong , Weng Xiu‐Fang , Tang Sheng‐An , Yan Jiu‐Xing , Li Shao‐Yong , Dong Wei‐Li , Ma Shi‐Kun
Published: April 2019

A pair of bridging chiral p‐t‐butylcalix[4]arenes (2a and 2b) (were) synthesized from 1 through homologous anionic ortho‐Fries rearrangement, and optically resolved with (1S)‐(+)‐10‐camphorsulfonyl chloride as chiral auxiliary. Bridging chiral p‐t‐butylcalix[4]arene tetrahydroisoquinolines (9a and 9b) as chiral organocatalysts for Henry reaction were designed and synthesized through the structural modification of 2a and 2b, respectively. Compared to the catalytic enantioselectivity of the unmodified tertiary amine (4b: ∼0% ee and 63% yield), those of the tetrahydroisoquinoline derivatives (9b: up to 13.4% ee and 96% yield) were distinctly enhanced. Although the increase magnitude of the catalytic ee is not remarkable, these catalytic results prove that the conformation inversion of calix[4]arene skeleton and the rotational freedom reduction of catalytic amine group indeed bring beneficial effects on the catalytic stereoselectivity.
Physicochemical and microbiological quality of the public water supply in 38 cities from the midwest region of the State of São Paulo, Brazil
Authors: Palmeira Ághata Regina de Oliveira Alves , da Silva Valdete Aparecida Terolo Higa , Dias Júnior Francisco Lopes , Stancari Regina Célia Arantes , Nascentes Gabriel Antonio Nogueira , Anversa Laís
Published: April 2019

The public water supply is a constant subject of concern since its quality depends on many different factors. The intention of this paper was to evaluate the quality of the public water supply in 38 cities from the midwest region of the State of São Paulo, Brazil, during the year of 2016. The parameters investigated included free residual chlorine,pH, apparent color, turbidity, fluoride, nitrate, and the presence of total coliforms andEscherichia coli. In total, from the 2,897 samples of water under analysis, 545 (18.81%) samples conflicted with the country's current legislation. The highest rates of noncompliance were related to fluoride contents and the presence of total coliforms. In addition, high nitrate concentrations (>10 mg/LNO3‐N) were observed in one of the cities’ water sample. Our data display the major critical points of the water offered to the population and expose the potential risks for human health, indicating the need of a regular surveillance of the water and the adoption of corrective and preventive measures, in order to avoid the waterborne diseases occurrence, thus contributing to the population's health improvement.

Practitioner points

Approximately 20% of the unsatisfactory water samples.

High nitrate concentrations in public supply water.

Potential risks for human health.
A new indicator of ionic polymeric flocculants for the removal of heavy metals anions: Specific charge density
Authors: Hou Rong , Zhao He , Cao Hongbin , Ning Jingheng
Published: April 2019

Ionic polymeric flocculants, as useful and widely used technology, have been applied for heavy metal pollution control. However, although molecular weight is an important indicator, it is not a comprehensive indicator for evaluating flocculation efficiencies of ionic flocculants. Herein, specific charge density (SCD), defined as charge density of unit molecular weight, is a new indicator to evaluate the performance of ionic polymer flocculants. Polydiallyldimethylammonium chloride (PDADMAC) as coagulant aid is investigated to flocculate different anionic pollutants. The results indicate that PDADMAC with a high SCD value could benefit to the flocculation efficiency of anionic pollutants. According to statistical analysis, the average pollutants residual could decrease to 8.64%–32.27% by that with high SCD value, especially for high valence pollutants with a decrease from 58.97%–60.40% to 27.35%–32.27%. The indicator of SCD values not only could characterize the performance of polymer flocculants but also provide a new sight of the flocculation mechanism of polymeric flocculants.

Practitioner points

Specific Charge Density (SCD) is defined as charge density of unit molecularweight.

SCD as a new indicator to evaluate comprehensively the performance of flocculants.

Removal efficiencies by flocculation increase with SCD value of PDADMAC increase.

Effect of SCD of PDADMAC on removal of pollutant with high valence is significant.

SCD of PDADMAC is less indicative for removal of pollutant with low valence.
Statistical analyses of flow rates of stormwater treatment bioretention media
Authors: Sileshi Redahegn , Pitt Robert E. , Clark Shirley E.
Published: April 2019

The design and performance of stormwater controls is affected by the treatment flow rates of bioretention media. This article presents the results of a large number of laboratory column tests conducted to examine the treatment flow rates for various mixtures of stormwater bioretention media. Statistical analyses were conducted to identify the treatment media having targeted treatment flow rates. It was found that the bioretention media treatment flow rates were most affected by the median particle size (D50) and uniformity coefficient (Cu) of the media, and the amount of organic matter. Statistical models were developed to evaluate and compare the treatment flow rates for various bioretention media mixtures. The findings of previous research (Sileshi, 2013) using two level, four factors (24, with varying texture [T], uniformity [U], organic content [OC], and compaction [C]) full‐factorial experiment study indicated that T and U of the media mixture have the greatest effect on the measured final infiltration rates of the media, followed by interactions of T and U; C; interactions of T and OC of the material; and interactions of U and OC of the material. As expected, media containing primarily larger particles (higher sand percentage) and, that is, uniformly graded (small uniformity coefficients) had the largest treatment flow rates. Compaction had minor effects if the organic matter content was low, but had significant effects on the flow rates for high organic matter content.

Practitioner points

Bioretention media treatment flow rates were most affected by the median particle size and uniformity coefficient of the media, and the amount of organic matter.

Statistical models were developed to evaluate and compare the treatment flow rates for various bioretention media mixtures.

The media containing primarily larger particles and, that is, uniformly graded (small uniformity coefficients) had the largest treatment flow rate.