bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mostly harmless simulations? Using Monte Carlo studies for estimator selection
Authors: Advani Arun , Kitagawa Toru , Słoczyński Tymon 
Published: June 2019

SummaryWe consider two recent suggestions for how to perform an empirically motivated Monte Carlo study to help select a treatment effect estimator under unconfoundedness. We show theoretically that neither is likely to be informative except under restrictive conditions that are unlikely to be satisfied in many contexts. To test empirical relevance, we also apply the approaches to a real‐world setting where estimator performance is known. Both approaches are worse than random at selecting estimators that minimize absolute bias. They are better when selecting estimators that minimize mean squared error. However, using a simple bootstrap is at least as good and often better. For now, researchers would be best advised to use a range of estimators and compare estimates for robustness.
Does institutional ownership affect information sharing with independent board members?
Authors: Smith Deborah D. , Meier Heidi H. , Alam Pervaiz 
Published: June 2019

AbstractResearch QuestionThis is an investigation of board independence to determine whether management shares information with the board, or withholds information to retain autonomy. A key contribution is to examine the interaction of institutional ownership with the main test variables to determine whether institutional governance influences the information environment as board independence is increased.Research FindingsThe results show that information asymmetry decreases internally and increases externally as board independence increases, yet institutional ownership appears to moderate or reverse this relationship. The following variables are used to explain why managers of firms are likely to have more information than outsiders: sticky SG&A costs, bid‐ask spread, and forecast error.Theoretical/Academic ImplicationsThe desired oversight from independent board members appears to be associated with reduced transparency between the firm and investors. Information sharing is lower for increased board independence when the firm's ownership is less sophisticated.Practitioner/Policy ImplicationsThese findings suggest that requiring increased board independence may reflect reduced transparency for firms with less institutional ownership. Further research should be conducted on the influence of institutional ownership on board member selection, and the relationship between management and board members appointed with institutional support.
Computational and artificial neural network based study of functional SNPs of human LEPR protein associated with reproductive function
Authors: Gandhi Muruganandhan Saranya , Manian Rameshpathy 
Published: June 2019

AbstractGenetic polymorphisms are mostly associated with inherited diseases, detecting and analyzing the biological significance of functional single‐nucleotide polymorphisms (SNPs) using wet laboratory experiments is an arduous task hence the computational analysis of putative SNPs is essential before conducting a study on a large population. SNP in the leptin receptor (LEPR) could result in the retention of intracellular signalling due to the structural and functional instability of the receptor causing abnormal reproductive function in human. In this first comprehensive computational analysis of LEPR gene mutation, we have identified and analyzed the functional consequence and structural significance of the SNPs in LEPR using recently developed several computational algorithms. Thirteen deleterious mutations such as W13C, S93G, I232R, Q307H, Y354C, E497A, Q571H, R612H, K656N, T690A, T699M V741M, and L760R were identified in the LEPR gene coding region. Backpropagation algorithm has been developed to forestall the deleterious nature of SNP and to validate the outcome of the tested computational tools. From ConSurf prediction three SNPs (Q571H, R612H, and T699M) were highly conserved on LEPR protein and the most deleterious variant R612H had one hydrogen bond abolished and severely reduced protein stability. Molecular docking suggested that the mutant (R612H) LEPR had lowest binding energy than native LEPR with the ligand molecule. Thus the energetically destructive changeover of ARG to HIS in R612H could possibly affect the LEPR protein structural stability and functional constancy due to interruption in the amino acid interactions and could result in reproductive disorders in human and increases the complication in obstetric and pregnancy outcome.
“The hook‐up”: How youth‐serving organizations facilitate network‐based social capital for urban youth of color
Authors: Dill LeConté J. , Ozer Emily J. 
Published: June 2019

AbstractYoung people of color residing in distressed urban contexts face challenges in accessing social capital that supports positive development and the transition to educational and employment opportunities. Youth‐serving organizations play potentially important roles for youth participants to access and leverage networks. This ethnographic study draws on qualitative interviews, conducted with adolescents at a youth‐serving organization based in East Oakland, California, to examine how network‐based social capital is activated and sustained for and by urban Black and Latinx youth. We found that relationships with supportive adult staff at the organization put youth in contact with caring, trusted adults of color outside of their families who serve as role models for them. These adults provide loving accountability to young people, serving as critical forces in distressed and stigmatized communities. We also found that adult staff activate social leverage to garner various current and future educational and professional opportunities for the youth there. These unique opportunities serve to boost young people's current self‐esteem and also to prime them to envision positive futures for themselves. Overall, these findings point to the importance of interpersonal pathways embedded within neighborhood institutions in the activation of network‐based social capital.
Endoscopic yield of chronic dyspepsia in outpatients: A single‐center experience in Cambodia
Authors: Oung Borathchakra , Chea Khang , Oung Chakravuth , Saurin Jean‐Christophe , Ko Cynthia W 
Published: June 2019

Background and AimThe diagnostic evaluation and management of patients with chronic dyspepsia may differ geographically according to patient age, prevalence of Helicobacter pylori or parasitic infection, and risk of gastric cancer. The characteristics and appropriate investigation of Cambodian patients with dyspepsia have not previously been studied. The aim of this study was to investigate the characteristics of Cambodian patients with chronic dyspepsia, the yield of upper endoscopy in these patients, and the value of alarm features in identifying patients with organic causes of dyspepsia.MethodsWe conducted a retrospective, single‐center study of 1231 adults with chronic dyspepsia who underwent upper endoscopy. We compared clinical characteristics, H. pylori prevalence, and endoscopic and histological findings of patients with functional or organic causes of dyspepsia. This study was approved by the National Ethics Committee for Health Research.ResultsThe majority of patients had overlapping symptoms of epigastric pain/burning and postprandial fullness/early satiety (40.6%), followed by epigastric pain/burning alone (29.7%) and postprandial fullness/early satiety alone (29.7%). Organic lesions were diagnosed in 6.9% of patients. The overall prevalence of H. pylori infection was 46% and was similar in the three clinical subgroups. The sensitivity and specificity of alarm features for organic causes of dyspepsia were 14 and 96%, respectively. The majority of patients with gastric cancer were 40 years of age or older.ConclusionsThe majority of patients with chronic dyspepsia seen at our outpatient center were diagnosed with functional or H. pylori‐associated dyspepsia. The presence of alarm features was not sensitive or specific for differentiating organic and functional dyspepsia.
Clinical impact of the sequentially‐checked drain removal criteria on postoperative outcomes after pancreatectomy: a retrospective study
Authors: Kosaka Hisashi , Satoi Sohei , Yamamoto Tomohisa , Hirooka Satoshi , Yamaki So , Kotsuka Masaya , Sakaguchi Tatsuma , Inoue Kentaro , Matsui Yoichi , Sekimoto Mitsugu 
Published: June 2019

AbstractBackgroundStrict criteria for impeccably safe drain management following pancreatectomy have not yet been developed. We evaluated the utility of the sequentially‐checked drain removal criteria by comparison with conventional criteria.MethodsPostoperative outcomes of 801 patients who underwent pancreatectomy, including 395 patients for whom drain fluid amylase (DFA) < 375U/l on postoperative day (POD) 3 (control group), were used and 406 patients for whom the sequentially‐checked criteria of DFA <5,000 U/l on POD 1 and DFA <3,000 U/l on POD 3 (sequentially‐checked group) were used and were retrospectively evaluated.ResultsDFA on POD 3 and fistula risk score did not differ between groups. Significantly more patients in the sequentially‐checked group met the criteria (control, 63.8% vs. sequentially‐checked, 76.1%, P < 0.001). The incidences of clinically relevant postoperative pancreatic fistula (CR‐POPF) (17.0% vs. 11.1%), intra‐abdominal abscess (21.0% vs. 9.1%) were significantly lower in the sequentially‐checked group (all P < 0.05). Multivariate analysis revealed that use of the sequentially‐checked criteria was significantly associated with CR‐POPF (odds ratio 0.601, 95% confidence interval [CI] 0.389–0.929; P = 0.022). C‐reactive protein <15 mg/dl at POD 3 was identified as an independent predictive factor for false positive CR‐POPF results in the sequentially‐checked group (odds ratio 0.872, 95% CI 0.811–0.939; P < 0.001); thus, this criterion was added to create the new triple‐checked criteria.ConclusionsThe sequentially‐checked criteria can provide safe drain management and improve postoperative outcomes.
Efficient Solvent‐Free Synthesis of Sucrose Esters via Sand‐Milling Pretreatment on Solid–Liquid Mixtures
Authors: Chen Jiazhi , Li Yuan , Chen Xiaotian , Mai Yuliang , Gao Minjie , Zhang Junjie , Wang Xi 
Published: June 2019

AbstractA general and efficient method, involving sand‐milling pretreatment and base‐catalyzed transesterification of sucrose and fatty acid methyl ester (FAME), was presented for the solvent‐free synthesis of sucrose esters. A metastable homogeneous paste with a solid particle size of 13 μm (D50) was obtained by milling at 1000 rpm for 1 h. This reaction mixture generated a total SE yield of 88.2% with a methyl stearate (MS) conversion of 91.4% using K2CO3 as a catalyst at 135 °C for 3 h at a stirring rate of 500 rpm, while those without milling (D50, 153 μm) yielded a total sucrose fatty acid esters (SE) of 49.3% with a MS conversion of 83.1% under the same reaction conditions. The reaction kinetics revealed that the reaction mixture with milling pretreatment displays a shorter induction time and a faster reaction rate for the formation of SE. The promotion of the solvent‐free synthesis of SE in the current study could be attributed to the reduction of solid particle sizes and the increased compatibility of solid–liquid phases. We believe that this strategy could be used as a general way for strengthening other heterogeneous reactions in the organic synthesis.
Percutaneous cryoablation for the treatment of extra‐abdominal desmoid tumors
Authors: Redifer Tremblay Kaila , Lea William B. , Neilson John C. , King David M. , Tutton Sean M. 
Published: June 2019

AbstractBackgroundDesmoid tumors are rare locally invasive, benign neoplasms that develop along aponeurotic structures. Current treatment is complicated by associated morbidity and high recurrence rates.MethodsA retrospective, single‐institution review identified 23 patients (age: 16‐77) with extra‐abdominal desmoid tumors who received CT‐guided percutaneous cryoablation as either a first‐line (61%) or salvage (39%) treatment in 30 sessions between 2014 and 2018. Median maximal lesion diameter was 69 mm (range: 11‐209). Intent was curative in 52% and palliative in 48%. Contrast‐enhanced cross‐sectional imaging was obtained before and after treatment in addition to routine clinical follow‐up.ResultsTechnical success was achieved in all patients. The median follow‐up was 15.4 months (3.5‐43.4). Symptomatic improvement was demonstrated in 89% of patients. At 12 months, the average change in viable volume was  −80% (range −100% to  + 10%) and response by modified response evaluation criteria in solid tumors (mRECIST) was CR 36%, PR 36%, and SD 28% No rapid postablation growth or track seeding was observed. Four patients underwent repeat cryoablation for either residual or recurrent disease. Two patients sustained a major procedural complication consisting of significant neuropraxia.ConclusionCryoablation for desmoid tumors demonstrates a high degree of symptom improvement and local tumor control on early follow‐up imaging with relatively low morbidity.
Rethinking Viscosupplementation: Ultrasound‐ Versus Landmark‐Guided Injection for Knee Osteoarthritis
Authors: Lundstrom Zachary T. , Sytsma Terin T. , Greenlund Laura S. 
Published: June 2019

ObjectivesViscosupplementation, intra‐articular injection of hyaluronic acid (HA), for knee osteoarthritis has fallen somewhat out of favor, with studies failing to show consistent benefits in pain reduction. Hyaluronic acid must enter the joint space to be beneficial; however, landmark‐guided injection can be substantially inaccurate, especially in obese patients. We aimed to determine whether ultrasound (US) guidance to ensure needle placement for HA knee injection resulted in improved outcomes as reflected by surgery‐free survival compared to landmark‐guided HA knee injection.MethodsAll community‐dwelling patients in 6 contiguous surrounding counties receiving HA knee injection either by landmark guidance (n = 647) or by US guidance (n = 500) were analyzed for the degree of arthritis, body mass index, follow‐up injection, and subsequent need for knee arthroplasty. A subgroup analysis of obese patients was also performed.ResultsThe US‐ and landmark‐guided HA injection cohorts were similar with respect to sex, body mass index, and the degree of arthritis. Of 1147 patients receiving knee HA injection, 462 subsequently underwent knee arthroplasty. Significantly fewer patients in the US‐guided HA injection cohort went to surgery (33.2%) compared to the landmark‐guided cohort (45.8%; P < .001). The subgroup analysis for obese patients showed even larger differences (34.8% versus 51.8%; P < .001).ConclusionsKnee osteoarthritis treatment by viscosupplementation can be optimized by US guidance, ensuring intra‐articular needle placement. Using an objective surgical outcome, our study shows that rethinking viscosupplementation to ensure intra‐articular delivery improves effectiveness. Patients receiving US‐guided knee HA injection were significantly less likely to undergo subsequent knee arthroplasty than patients receiving landmark‐guided HA injection.
Altered facial muscle innervation pattern in patients with postparetic facial synkinesis
Authors: Raslan Ashraf , Guntinas‐Lichius Orlando , Volk Gerd Fabian 
Published: June 2019

Objectives/HypothesisUsing surface electrostimulation, we aimed to use facial nerve mapping (FNM) in healthy subjects and patients with postparetic facial synkinesis (PPFS) to define functional facial target regions that can be stimulated selectively.Study DesignSingle‐center prospective cohort study.MethodsFNM was performed bilaterally in 20 healthy subjects and 20 patients with PPFS. Single‐pulse surface FNM started at the main trunk of the facial nerve and followed the peripheral branches in a distal direction. Stimulation started with 0.1 mA and increased in 0.1 mA increments. The procedure was simultaneously video recorded and evaluated offline.ResultsA total of 1,873 spots were stimulated, and 1,875 facial movements were evaluated. The stimulation threshold was higher on the PPFS side (average = 9.8 ± 1.0 mA) compared to the contralateral side (4.1 ± 0.8 mA) for all stimulation sites or compared to healthy subjects (4.1 ± 0.5 mA; all P < .01). In healthy subjects, selective electrostimulation ± one unintended coactivation was possible at all sites in >80% of cases, with the exception of pulling up the corner of the mouth (65%–75%). On the PPFS side, stimulation was possible for puckering lips movements in 60%/75% (selective stimulation ± one coactivation, respectively), blinking in 55%/80%, pulling up the corner of the mouth in 50%/85%, brow raising in 5%/85, and raising the chin in 0%/35% of patients, respectively.ConclusionsFNM mapping for surgical planning and selective electrostimulation of functional facial regions is possible even in patients with PPFS. FNM may be a tool for patient‐specific evaluation and placement of electrodes to stimulate the correct nerve branches in future bionic devices (e.g., for a bionic eye blink).Level of Evidence2bLaryngoscope, 130:E320–E326, 2020
Dynamics of benthic metabolism, O2, and pCO2 in a temperate seagrass meadow
Authors: Berg Peter , Delgard Marie Lise , Polsenaere Pierre , McGlathery Karen J. , Doney Scott C. , Berger Amelie C. 
Published: June 2019

AbstractSeagrass meadows play an important role in “blue carbon” sequestration and storage, but their dynamic metabolism is not fully understood. In a dense Zostera marina meadow, we measured benthic O2 fluxes by aquatic eddy covariance, water column concentrations of O2, and partial pressures of CO2 (pCO2) over 21 full days during peak growing season in April and June. Seagrass metabolism, derived from the O2 flux, varied markedly between the 2 months as biomass accumulated and water temperature increased from 16°C to 28°C, triggering a twofold increase in respiration and a trophic shift of the seagrass meadow from being a carbon sink to a carbon source. Seagrass metabolism was the major driver of diurnal fluctuations in water column O2 concentration and pCO2, ranging from 173 to 377 μmol L−1 and 193 to 859 ppmv, respectively. This 4.5‐fold variation in pCO2 was observed despite buffering by the carbonate system. Hysteresis in diurnal water column pCO2 vs. O2 concentration was attributed to storage of O2 and CO2 in seagrass tissue, air–water exchange of O2 and CO2, and CO2 storage in surface sediment. There was a ~ 1:1 mol‐to‐mol stoichiometric relationship between diurnal fluctuations in concentrations of O2 and dissolved inorganic carbon. Our measurements showed no stimulation of photosynthesis at high CO2 and low O2 concentrations, even though CO2 reached levels used in IPCC ocean acidification scenarios. This field study does not support the notion that seagrass meadows may be “winners” in future oceans with elevated CO2 concentrations and more frequent temperature extremes.
Transformation of Thioester‐Initiated Star Polymers into Linear Arms via Native Chemical Ligation
Authors: Aksakal Suzan , Aksakal Resat , Becer Caglar Remzi 
Published: June 2019

AbstractThe synthesis of a new class of Cu‐mediated polymerization initiators with thioester functionality is demonstrated and their polymerization kinetics via single‐electron transfer living radical polymerization is reported. From periodic sampling, it is found that thioester‐ or ester‐based initiators can be employed interchangeably, resulting in very similar polymerization rates. Furthermore, a multifunctional thioester initiator is employed for the preparation of a well‐defined four‐arm star‐shaped polymer. It is further shown that the full dissociation of the star polymer into linear arms via native chemical ligation can easily be followed via size exclusion chromatography, as a result of the change in hydrodynamic volume. Finally, the obtained linear polymers are characterized via matrix‐assisted laser desorption/ionization–time of flight mass spectrometry and found to be in good agreement with the expected molecular weight distribution that confirms the successful transformation.
SNCA Rep1 promoter variability influences cognition in Parkinson's disease
Authors: Ng Adeline S.L. , Tan Yi Jayne , Zhao Yi , Saffari Seyed Ehsan , Lu Zhonghao , Ng Ebonne Y.L. , Ng Samuel Y.E. , Chia Nicole S.Y. , Setiawan Fiona , Xu Zheyu , Tay Kay Yaw , Au Wing Lok , Tan Louis C.S. , Tan Eng‐King 
Published: June 2019

AbstractBackgroundWhile the association between alpha‐synuclein gene promoter (Rep1) variability and risk of PD is well established, its association with cognition is unclear.ObjectivesTo investigate the association between Rep1 and motor and cognitive outcomes in PD.MethodsRep1 allele lengths were determined in 172 PD patients who were grouped into “long” and “short” carriers according to previous methods. Multivariable regression analysis was performed to investigate the effect of Rep1 length on cognitive and motor scores.ResultsLong Rep1 allele carriers had significantly lower MMSE (P = 0.010) and higher UPDRS Part III (P = 0.026) and H & Y (P = 0.008) scores compared to short allele carriers (controlled for age, sex, and disease duration). Interaction analyses of Rep1 with apolipoprotein 4 revealed no significant effect on clinical outcomes.ConclusionsPD patients carrying long Rep1 alleles are more impaired on cognitive and motor function independent of apolipoprotein 4 genotype. © 2019 International Parkinson and Movement Disorder Society
Transparent dual band Wi‐Fi filter for double glazed energy saving window as a smart network
Authors: Pakdin Mahdi , Ghayekhloo Alireza , Rezaei Pejman , Afsahi Majid 
Published: June 2019

AbstractA transparent advanced electromagnetic structure is designed to be used in real‐world Wi‐Fi shielding applications. Concentric square loops as frequency selective surfaces (FSSs) are analytically presented with the Pyrex glass substrate based on the equivalent electric circuit model. The designed FSS window suppresses signals at both 2.5 and 5 GHz bands, and reflects back to the indoor medium. Visible light transmittance of the studied window is achieved as 87%. Accordingly, other electromagnetic communication links can transfer through the designed filter such as cell phone, and radio. The dependency of the proposed window to polarization and angular variations is examined numerically, which shows stable frequency response at 2.5 GHz and an acceptable one for 5 GHz. As a figure of merit, the proposed structure is a double glazed window with potential application for smart, secure, and energy‐saving buildings. Also, practical considerations regarding the deployment of FSS on window glass and the separation distance between the glass layers have been investigated. A prototype of the proposed design is fabricated and measured that a good agreement between measurement and simulation is demonstrated. Therefore, parametric circuit model analysis, deployment of transparent substrate, thin metallic parts on one layer, secure indoor communications, and energy‐saving are some of the advantages of the proposed window.
Low loss semi‐MIM hybrid plasmonic waveguide with high electric field confinement
Authors: Manzoor Zahra , Mirala Ali , Pak Amin , Panahi Mohammad A. 
Published: June 2019

AbstractAmong different types of plasmonic waveguides that support surface‐plasmon‐polariton (SPP) mode, metal‐insulator‐metal (MIM) waveguides have the best electric field confinement in expense of high propagation loss. On the other hand, hybrid plasmonic waveguides (HPWGs) are represented as low loss plasmonic waveguides with moderate confinement. In this work, a new design of HPWG is proposed with higher electric field confinement compare with conventional HPWG by adding lossy spacer layer to the designed HPWG. This modification causes the proposed design be more similar to metal‐insulator‐metal (MIM) waveguides but with less propagation loss. The proposed design is called semi‐MIM HPWG and its structure is studied analytically and numerically. Dimensions of the proposed semi‐MIM HPWG is optimized to work at 193.5 THz and the proper stepped taper transition is designed to feed the waveguide by photonic feed lines.