bluuebunny/crossref_metadata_2025 huggingface dataset:
Resilience of BST-2/Tetherin structure to single amino acid substitutions
Authors: Roy Ian R. , Sutton Camden K. , Berndsen Christopher E.
Published: May 2019

Human tetherin, also known as BST-2 or CD317, is a dimeric, extracellular membrane-bound protein that consists of N and C terminal membrane anchors connected by an extracellular domain. BST-2 is involved in binding enveloped viruses, such as HIV, and inhibiting viral release in addition to a role in NF-kB signaling. Viral tethering by tetherin can be disrupted by the interaction with Vpu in HIV-1 in addition to other viral proteins. The structural mechanism of tetherin function is not clear and the effects of human tetherin mutations identified by sequencing consortiums are not known. To address this gap in the knowledge, we used data from the Ensembl database to construct and model known human missense mutations within the ectodomain to investigate how the structure of the ectodomain influences function. From the data, we identified an island of sequence stability within the ectodomain, which corresponds to a functionally and structurally important region identified in previous biochemical and biophysical studies. Most of the modeled mutations had little effect on the structure of the dimer and the coiled-coil, suggesting that the coiled-coil compensates for changes in primary structure. Thus, many of the functional defects observed in previous studies may not be due to changes in tetherin structure, but rather, due to in changes in protein-protein interactions or in aspects of tetherin not currently understood. The lack of structural effects by mutations known to decrease function further illustrates the need for more study of the structure-function connection for this system. Finally, apparent flexibility in tetherin sequence may allow for greater anti-viral activities with a larger number of viruses by reducing specific interactions with anti-tetherin proteins, while maintaining virus restriction.
JOGOS DIDÁTICOS PARA O ENSINO DE CIÊNCIAS NATURAIS E MATEMÁTICA NO ATENDIMENTO PEDAGÓGICO DOMICILIAR / DIDACTIC GAMES FOR THE TEACHING OF SCIENCES AND MATHEMATICS IN THE PEDAGOGICAL HOME CARE
Authors: Silva Margarete Virgínia Gonçalves , Hussein Fabiana Roberta Gonçalves e Silva , Marques Carlos Alberto
Published: May 2019

Este trabalho é parte do estudo realizado com professores que atuam no programa de Atendimento Pedagógico Domiciliar da SEED de Curitiba – PR, discutindo suas concepções quanto à utilização de jogos didáticos no ensino e aprendizagem de conceitos científicos das disciplinas de Ciências Naturais e Matemática. Busca-se ainda evidenciar e problematizar a estratégia dos jogos didáticos como fator de contribuição para o desenvolvimento de habilidades cognitivas e da autoestima do aluno-paciente, seriamente comprometida em função de sua doença. A produção e elaboração dos jogos foi artesanal. A metodologia da pesquisa e de análise de dados com os professores foi a de estudo de caso com enfoque qualitativo. Para os professores entrevistados, os jogos didáticos apresentam-se como uma boa estratégia de ensino, enriquecendo as aulas e proporcionando aos alunos nessa condição de APD uma oportunidade de aquisição do conhecimento de forma eficiente e também divertida.
RESOLUÇÃO DE PROBLEMAS: UMA PRÁTICA REALIZADA POR PROFESSORES COM ALUNOS DO ENSINO MÉDIO / PROBLEM-SOLVING: A PRACTICE PERFORMED BY MATH TEACHERS WITH HIGH SCHOOL STUDENTS
Authors: Kliemann Geovana Luiza , Dullius Maria Madalena
Published: May 2019

Este estudo objetiva auxiliar professores de Matemática a fazerem uso da metodologia de resolução de problemas em suas aulas, desvinculado de conteúdos específicos. Para atingir o objetivo, foi realizado um estudo qualitativo, a partir do qual organizou-se um material pedagógico que foi experimentado e problematizado por sete professores com seus respectivos alunos do 1º ano do Ensino Médio de seis escolas públicas, do Vale do Taquari, RS. A partir dos relatos, escritos e falados dos professores sujeitos da pesquisa e da observação participante dos pesquisadores a algumas aulas, emergiram diferentes categorias.Como resultados, é possível destacar que os educadores apresentaram capacidade para inovar, mostrando que o apoio a partir de material concreto pode ser bastante significativo. Concluiu-se, também, que um profissional sozinho apresenta maior dificuldade em diversificar sua prática, porém, com pequenos incentivos é capaz de realizar inovações positivas que beneficiam a aprendizagem de seus alunos.
Investigations on Bacteriological Quality of Tap Water Sources within the University of Port Harcourt
Authors: Stanley H. O. , Ugboma C. J. , Uzoaru P. C.
Published: May 2019

In this study, the sanitary quality of tap water sources within the University of Port Harcourt was investigated in order to determine its suitability for drinking and other domestic applications. Eight composite samples of tap water were collected from Eight different locations within the three campuses of the University of Port Harcourt using 300 ml-capacity sterile containers. These locations included NDDC Hostel, Sports Hostel, Medical Hostel, NUH Hostel, Dan Etete Hostel, Delta A Hostel, Delta B Hostel and Choba Campus. After collection, water samples were taken to the laboratory for enumeration and identification of Total heterotrophic bacteria (THB), Total coliform (TC) and Faecal coliform (FC) using the membrane filtration method. Result showed that the average THB, TC and FC counts recorded in the tap water samples across the eight locations ranged from 12.4 CFU to 36.7 CFU, 4.3 CFU to 10.1 CFU and 2.8 CFU to 5.2 CFU per 100ml respectively. Bacterial isolates were identified as probably belonging to genera such as Bacillus spp., Klebsiella spp., Enterobacter spp., Staphylococcus spp., Proteus spp., Citrobacter spp., Serratia spp. and Escherichia spp., respectively. Samples from Delta B hostel and Choba campus recorded the lowest and highest THB, TC and FC counts respectively. According to WHO standard, the result of THB, TC and FC counts indicated that the tap water in all eight locations were above the limit acceptable for drinking but within acceptable limit for other domestic use such as bathing and washing.
Opinions of Pregnant Womens Intended to Male Midwives
Authors: Bolsoy Nursen , Sen Selma , Ulas Seval Cambaz , Durgun Seçil Köken
Published: May 2019

Aim: The study was conducted to determine opinion of pregnant women about their gender preferences related with midwife profession.

Methods: The study was conducted in cross-sectional and descriptive type. Whereas the research universe was consisted of 2954 pregnant women,the sampling group was including 384 pregnant women. The study was conducted in three randomly-selected Family Health Centers under the jurisdiction of the Manisa Public Health Directorship. The questionnaire consisted of 42 questions, developed by the researchers was harnessed in data collection process. In analysis process of the collected data, mean, percentage and chi-square methods were utilized.

Results: It was determined that although 52.2% of pregnant women agree with the opinion that both women and men could participate in childbearing operation; 97.9% of women preferred to have service from a midwife; and 98.4% preferred to have assistance from a woman midwife. When descriptive characteristics of pregnant women and their opinions regarding gender preferences in midwifery are compared, it was determined that whereas no any statistically significant difference was determined with age, education status, marital status, longest residential place, social security and family types of pregnant women (p>0.05); a statistically significant difference was determined with their employment status, one of their descriptive characteristic (p<0.05).

Conclusion: Whereas majority of pregnant women agree with the opinion that men could be midwife; when it comes to receiving service from midwife during delivery, almost all of them preferwomen midwives. Therefore, if key role of midwives in enhancement of public health are taken into consideration, childbearing, pre- and post-partum care services are especially required to be provided by women midwives.
White‐Light Emission from Dual‐Way Photon Energy Conversion in a Dye‐Encapsulated Metal–Organic Framework
Authors: Wang Zheng , Zhu Cheng‐Yi , Mo Jun‐Ting , Fu Peng‐Yan , Zhao Yan‐Wu , Yin Shao‐Yun , Jiang Ji‐Jun , Pan Mei , Su Cheng‐Yong
Published: May 2019

The design of white‐light phosphors is attractive in solid‐state lighting (SSL) and related fields. A new strategy in obtaining white light emission (WLE) from dual‐way photon energy conversion in a series of dye@MOF (LIFM‐WZ‐6) systems is presented. Besides the traditional UV‐excited one‐photon absorption (OPA) pathway, white‐light modulation can also be gained from the combination of NIR‐excited green and red emissions of MOF backbone and encapsulated dyes via two‐photon absorption (TPA) pathway. As a result, down‐conversion OPA white light was obtained for RhB+@LIFM‐WZ‐6 (0.1 wt %), BR‐2+@LIFM‐WZ‐6 (2 wt %), and APFG+@LIFM‐WZ‐6 (0.1 wt %) samples under 365 nm excitation. RhB+@LIFM‐WZ‐6 (0.05 wt %), BR‐2+@LIFM‐WZ‐6 (1 wt %) and APFG+@LIFM‐WZ‐6 (0.05 wt %) exhibit up‐conversion TPA white light under the excitation of 800, 790, and 730 nm, respectively. This new WLE generation strategy combines different photon energy conversion mechanisms together.
Inverse‐Electron‐Demand Palladium‐Catalyzed Asymmetric [4+2] Cycloadditions Enabled by Chiral P,S‐Ligand and Hydrogen Bonding
Authors: Wang Ya‐Ni , Xiong Qin , Lu Liang‐Qiu , Zhang Qun‐Liang , Wang Ying , Lan Yu , Xiao Wen‐Jing
Published: May 2019

Catalytic asymmetric cycloadditions of ambident Pd‐containing dipolar species with nucleophilic dipolarophiles, namely, inverse‐electron‐demand cycloadditions, are challenging and underdeveloped. Possibly, the inherent linear selectivity of Pd‐catalyzed intermolecular allylations and the lack of efficient chiral ligands are responsible for this limitation. Herein, two cycloadditions of such intermediates with deconjugated butenolides and azlactones were accomplished by using a novel chiral hybrid P,S‐ligand and hydrogen bonding. By doing so, highly functionalized, optically active dihydroquinol‐2‐ones were produced with generally high reaction efficiencies and selectivities. Preliminary DFT calculations were performed to explain the high enantio‐ and diastereoselectivities.
Unprecedented isolation of a dinuclear tin (II) complex stabilized by pyridine‐2,6‐dimethanol: structure, DFT and in vitro screening of cytotoxic properties
Authors: I. Mantasha , Raza Md Kausar , Shahid M. , Ansari Azaj , Ahmad Musheer , Khan Ishaat M.
Published: May 2019

In this work, we report a novel dinuclear Sn (II) complex, [Sn2(Hpdm)2(H2O)6] 2H2O 2Cl (1) (H2pdm = pyridine‐2,6‐dimethanol), which has been crystallized out and characterized by elemental analysis, FTIR, 1H and 13C NMR, single crystal X‐ray studies and Density Functional Theory (DFT) analysis. X‐ray structure of 1 has confirmed it to be a dinuclear alkoxo‐bridged Sn (II) species where each metal adopts a seven coordinate distorted pentagonal bipyramidal (pbp) geometry. This is the first hepta‐coordinated Sn (II) complex ever isolated apart from already reported stannylenes. Spin density plots from DFT support the +2 oxidation state of each tin metal. Hirshfeld surface analysis reveals the presence of various H‐bonding interactions in the molecule and molecular docking results along with DFT confirm higher binding affinity of the present complex towards DNA. Moreover, the complex exhibits promising anticancer activities against HeLa and A549 cancer cell lines.
Morphological evaluation and phase behavior of PVDF/PEO blends in the presence of graphene nanoplatelets through rheological measurements
Authors: Mohamadi Mahboube , Papila Melih , Garmabi Hamid , Gohari Bajestani Zahra
Published: May 2019

In this study, graphene nanoplatelets (GNPs) were incorporated into poly(vinylidene fluoride) (PVDF), poly(ethylene oxide) (PEO), and PVDF/PEO blends using solution casting method in order to achieve binary and ternary polymer nanocomposites. The focus of the work is on the compatibilizing effects of the GNPs on partially miscible PVDF/PEO blends. X‐ray diffraction method, rheological measurements, scanning electron microscopy (SEM), and atomic force microscopy observations enabled us to track the dispersion state and localization of the graphene nanosheets in the nanocomposites. The results exhibited that the nanoplatelets were preferentially distributed through the PVDF phase and/or at the interface of the PVDF/PEO phases. Evaluation of the wetting parameter for the PVDF/PEO/GNPs nanocomposite also verified better affinity of the selected nanofiller with the PVDF component. Extend of the miscibility in the nanocomposites was studied by a well‐known rheological method. A tangible increment in binodal (Tb) and spinodal (Ts) decomposition temperatures by addition of a very low content of the GNPs (0.5 wt %) revealed well‐defined compatibilization effects of the graphene on this binary polymer blend. SEM images at different temperatures confirmed the rheologically determined liquid–liquid phase diagram. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48017.
Pharmacokinetics of cligosiban in dog plasma after oral administration by liquid chromatography electrospray ionization tandem mass spectrometry
Authors: Xi Wang , Zou Qiaogen , Ouyang Pingkai
Published: May 2019

In this study, a simple and reliable liquid chromatography coupled with Q‐Exactive‐Orbitrap–MS was developed and validated for detecting and quantifying cligosiban and its metabolites in dog plasma after oral administration. The plasma samples were pretreated with acetonitrile and separated on a Diamonsil C18 column (4.6 × 100 mm, i.d. 3 μm) with 0.1% formic acid in water and acetonitrile as mobile phase. The method was validated according to the guidance of the US Food and Drug Administration. The assay was linear over the tested concentration ranges with coefficients of correlation >0.995. The extraction recovery was >83.23% with RSD <15%. Precision was <9.31% and accuracy ranged from −4.40 to 10.20%. The method was free of matrix effects. Under the conditions used, four metabolites were detected and their identities were identified by accurate masses and fragment ions. M1 and M3 were further confirmed by reference standards. The biotransformation pathways included demethylation and glucuronidation. The validated method was further applied to quantify cligosiban, M1 and M3 in dog plasma. After oral administration, cligosiban was detectable in dog plasma and reached the maximum concentration at ~1.67 ± 0.58 h post‐dose. It was rapidly eliminated with a half‐life of 3.48 ± 0.80 h. M1 showed high plasma exposure with its area under the curve being 23.31% of that of cligosiban.
Differences between physicians' and nurse practitioners' viewpoints on reasons for clozapine underprescription
Authors: Okhuijsen‐Pfeifer Cynthia , Cohen Dan , Bogers Jan P. A. M. , de Vos Cato M. H. , Huijsman Elianne A. H. , Kahn René S. , Luykx Jurjen J.
Published: May 2019

Introduction

Clozapine (CLZ) is the only proven effective therapy for treatment‐resistant schizophrenia, but it is underutilized across the globe. Previous findings suggest a lack of experience with CLZ prescription and concerns about CLZ's pharmacological characteristics are the prime reasons for CLZ underutilization. To our knowledge, it is currently unknown whether the reasons for underutilization and suggested solutions differ between physicians and nurse practitioners. Such differences are important as nurse practitioners are becoming increasingly involved in prescribing CLZ.

Methods

To examine to what degree physicians and nurse practitioners differ with regard to their take on reasons for CLZ underutilization and suggested solutions, an online questionnaire was distributed to physicians and nurse practitioners. The primary outcome was to compare the patient‐related and prescriber‐related reasons for CLZ underprescription between physicians and nurse practitioners, while secondary outcome measures included the potential solutions to prevent this underprescription.

Results

Physicians (N = 112) and nurse practitioners (N = 41) agreed that the two most common reasons for underprescription (patient‐related and prescriber‐related) were refusal to undergo regular blood tests and side‐effect concerns. They also agreed that the third most common prescriber‐related reason was medical complications. Physicians rated patients' unwillingness to switch medication as the third most common reason for CLZ underprescription, whereas nurse practitioners rated refusal to undergo baseline bloodtests as the third most common reason. The solutions to reduce underprescription largely corresponded between both groups.

Conclusions

We conclude that slight differences exist between physicians' and nurse practitioners' viewpoints on patient‐related and prescriber‐related reasons for CLZ underprescription. Future research projects should involve patients to elucidate whether the patient‐related factors put forward by prescribers align with the patients' opinions.
Response to pneumococcal vaccination in multiple myeloma
Authors: Renaud Loïc , Schraen Susanna , Fouquet Guillemette , Guidez Stephanie , Demarquette Hélène , Nudel Morgane , Cayssials Emilie , Bories Claire , Herbaux Charles , Systchenko Thomas , Faucompré Jean‐Luc , Machet Antoine , Sabirou Florence , Levy Antony , Bobin Arthur , Richez Valentine , Moya Niels , Gruchet Cécile , Desmier Deborah , van de Wyngaert Zoe , Carpentier Benjamin , Manier Salomon , Facon Thierry , Harding Stephen , Leleu Xavier
Published: May 2019

Background

Streptococcus pneumoniae infection causes morbidity and mortality in multiple myeloma patients. Pneumococcal vaccination is commonly given to immunocompromised myeloma patients; however response data are sparse. Here, we present longitudinal response data to pneumococcal vaccination in multiple myeloma patients.

Method

Twenty‐eight multiple myeloma patients were included, 25 of whom were newly diagnosed. All the patients received two vaccines Prevnar13® and Pneumo23®. Serotype‐specific IgG was measured by ELISA for all 23 vaccine serotypes at baseline, and then sequentially at different time points postvaccination until treatment ended. Response to vaccination is available for 20 patients. The primary endpoint was the incidence rate of patients who obtained an isotype response serum concentration after vaccination. Secondary endpoints included detailed isotype increase, time to first increase, further assessment of a decreased anti‐pneumococcal serum concentrations following treatment including autologous stem cell transplantation (ASCT), rate of infection with a special attention to pneumococcal infection.

Results

The median age was 66 years and the male to female ratio was 0.6. Anti‐pneumococcal capsular polysaccharide (anti‐PCP23) IgG, IgG2, IgA, and IgM responses were detected within 1 week postvaccination. Response to at least one subtype of antibody was obtained in 85% (n = 17) of patients, for at least two subtypes in 65% (n = 13), for at least three subtypes in 55% (n = 11), and 2 patients responded to all four subtypes. The median increase in the concentration of anti‐PCP23 isotypes was threefold following vaccination, with the highest increase observed when Pneumo23® was given more than 30 days after Prevnar13®. The anti‐pneumococcal geometric mean concentration decreased significantly for all subtypes over time independently of treatment approaches.

Conclusion

Myeloma has the ability to demonstrate a response to pneumococcal vaccine, independently of preexisting hypogammaglobulinemia and possibly of treatment‐induced immunodepression. We also observed a drop in the serum response overtime and following autologous transplantation. Further studies in larger sample are needed to understand the benefit of vaccination strategies in these patients.
Dialectical behaviour therapy and 12‐step programmes for substance use disorder: A systematic review and meta‐analysis
Authors: Giannelli Ezechiele , Gold Christian , Bieleninik Lucja , Ghetti Claire , Gelo Omar C. G.
Published: May 2019

Background

Research on dialectical behaviour therapy (DBT) or 12‐step programmes has shown inconclusive results; no systematic review has directly compared the two.

Objectives

The goals of this meta‐analytic review were to assess if DBT is more effective than treatment as usual (TAU) and if DBT is more effective than 12‐step programmes (including twelve‐step facilitation [TSF] and self‐help groups like Alcoholics Anonymous) for substance use disorder (SUD).

Methods

We searched for randomised controlled trials (RCTs) and extracted data on the following outcomes: reduction in substance use, retention in treatment, severity of substance dependence/abuse and severity of mental health symptoms. Studies involved adult (>18 years) women with SUD, according to DSM‐5 or the equivalent diagnoses in DSM‐IV. Three RCTs met the inclusion criteria and contained appropriate data for meta‐analysis (75 participants).

Results

No significant effects of DBT have been found compared to 12‐step programmes. Comparing DBT with TAU, we found a beneficial short‐term (1 RCT, n = 12, SMD = −0.84; 95% CI [−1.64, −0.04]) and long‐term (2 RCTs, n = 29, SMD = −1.26; 95% CI [−2.13, −0.40]) effect of DBT on severity of substance use.

Conclusions

Despite the limited evidence of the present review, contextual evidence supports DBT and 12‐step programmes. RCTs with larger sample sizes are needed to better elucidate the impact of both treatments on SUD and facilitate the comparison between DBT and 12 steps programmes.
Not just who you are, but who you were before: Social identification, identity incompatibility, and performance‐undermining learning behaviour in higher education
Authors: Smyth Lillian , Mavor Kenneth I. , Gray Louie R.
Published: May 2019

The current study builds on links between academic social identification and learning behaviours and extends these models by also considering the level of compatibility between the student identity and the pre‐existing self‐concept. This is a crucial extension, in the context of broadening access to higher education and fostering belonging and learning in nontraditional students. Further, where previous work focused on learning behaviours that enhance performance (often learning approaches), we also consider performance‐undermining behaviours (self‐handicapping and procrastination). These effects are explored in survey responses from an undergraduate student sample (N = 121) from UK and broader European samples. Participants were predominantly female (69%) and native English speakers (87%). Three models of the relationships between these variables were tested using Mplus. Results indicate that performance‐undermining behaviours are predicted by identity incompatibility, but not identification level; deep learning approaches are predicted by identification level, but not identity incompatibility. This provides first evidence that identity incompatibility is not just a moderator of the identification‐learning relationships but, in fact, a separate identity process for consideration. We also present initial evidence for a mediation model, where in the identity variables are related to procrastination and self‐handicapping via learning approaches.
Very Bright Phycoerythrobilin Chromophore for Fluorescence Biolabeling
Authors: Hou Ya‐Nan , Ding Wen‐Long , Hu Ji‐Ling , Jiang Xiang‐Xiang , Tan Zi‐Zhu , Zhao Kai‐Hong
Published: May 2019

Biliproteins have extended the spectral range of fluorescent proteins into the far‐red (FR) and near‐infrared (NIR) regions. These FR and NIR fluorescent proteins are suitable for the bioimaging of mammalian tissues and are indispensable for multiplex labeling. Their application, however, presents considerable challenges in increasing their brightness, while maintaining emission in FR regions and oligomerization of monomers. Two fluorescent biliprotein triads, termed BDFP1.2/1.6:3.3:1.2/1.6, are reported. In mammalian cells, these triads not only have extremely high brightness in the FR region, but also have monomeric oligomerization. The BDFP1.2 and BDFP1.6 domains covalently bind to biliverdin, which is accessible in most cells. The BDFP3.3 domain noncovalently binds phycoerythrobilin that is added externally. A new method of replacing phycoerythrobilin with proteolytically digested BDFP3.3 facilitates this labeling. BDFP3.3 has a very high fluorescence quantum yield of 66 %, with maximal absorbance at λ=608 nm and fluorescence at λ=619 nm. In BDFP1.2/1.6:3.3:1.2/1.6, the excitation energy that is absorbed in the red region by phycoerythrobilin in the BDFP3.3 domain is transferred to biliverdin in the two BDFP1.2 or BDFP1.6 domains and fluoresces at λ≈670 nm. The combination of BDFP3.3 and BDFP1.2/1.6:3.3:1.2/1.6 can realize dual‐color labeling. Labeling various proteins by fusion to these new fluorescent biliproteins is demonstrated in prokaryotic and mammalian cells.
Selective Aerobic Oxidation of Lactate to Pyruvate Catalyzed by Vanadium‐Nitrogen‐Doped Carbon Nanosheets
Authors: Zhang Wei , Oulego Paula , Slot Thierry K. , Rothenberg Gadi , Shiju N. Raveendran
Published: May 2019

The catalytic oxidative dehydrogenation of lactates with molecular oxygen is a promising yet challenging route for producing high‐value pyruvates from biomass. Here we report a simple synthetic strategy for preparing nitrogen‐doped carbon nanosheets (NCNs) starting from two abundant precursors, cheap melamine and glucose, and using a simple thermal‐annealing process. The resulting NCNs feature numerous edges and holes for anchoring vanadium oxides (V‐NCNs). This creates cooperative catalytic sites that boost the catalytic oxidation of ethyl lactate to ethyl pyruvate. Additionally, we systematically studied the surface nitrogen species of NCNs by varying the pyrolysis temperature, and found that the active pyridinic N‐oxide species formed in a high thermal‐annealing treatment, acting synergistically with vanadium active sites in converting ethyl lactate with oxygen into ethyl pyruvate under mild conditions.
Effect of light irradiation on esterification of oleic acid with ethanol catalyzed by immobilized Pseudomonas cepacia lipase
Authors: Ong Huei Ruey , Ganasen Ponnarasy , Abul Kalam Md. , Ethiraj Baranitharan , Mahmud Mohd Sabri , Maksudur Rahman Khan Md.
Published: May 2019

The present study demonstrates the effect of light irradiation on the esterification of oleic acid catalyzed by immobilized Pseudomonas cepacia lipase. The reaction rates of all the experiments under light irradiation were found to be higher than dark conditions. The kinetics of reactions supported the Ping‐Pong Bi‐Bi mechanism with dead end inhibition by both the alcohol and acid substrates. Moreover, circular dichroism (CD) spectroscopy was used to analyze the effect of light on lipase enzyme. The CD spectroscopic studies confirmed that the conformational changes in the secondary structure of the lipase enzyme increased the reaction rate of light‐illuminated experiments, which might have opened up the active sites of enzymes and thus, resulted in higher reaction rates compared to dark reactions. These results have successfully demonstrated that the light illumination positively influenced the rate of P. cepacia enzyme‐catalyzed esterification reactions.
Modelling and experimental study of hydrate formation kinetics of natural gas‐water‐surfactant system in a multi‐tube bubble column reactor
Authors: Xin Ya′nan , Zhang Jianwen , He Yingwei , Wang Chuansheng
Published: May 2019

To promote the heat and mass transfer during the hydrate formation process, an internal spiral‐grooved tube (ISGT) was proposed as the reaction tube in a large‐scale multi‐tube bubble column reactor with external slurry circulation. In order to investigate such multi‐component gas (natural gas)‐water‐surfactant systems during the hydrate formation process in the ISGT, based on the solute permeation model and Kolmogorov isotropic turbulence theory, a CFD method combined with the population balance model (PBM) was utilized to simulate gas‐liquid mass transfer coefficient. Then, the hydrate formation kinetics model in ISGT was modelled based on the model proposed by Kashchiev and Firoozabadi. The hydrate formation experiments were carried out in the multi‐tube bubble column reactor at six different pressure‐temperature‐circulating flow velocities of piston pump regimes to investigate the actual formation process of natural gas hydrate. The experimental results were then used to finetune the optimized parameters to facilitate accurate model predictions.
Atypical cytological changes mimicking SIL of the uterine cervix in allogenic hematopoietic stem cell transplantation recipients treated with busulfan
Authors: Saco Adela , Alòs Silvia , Esteve Roser , Suárez‐Lledó María , Martínez Carmen , Perez Francisco M. , Vega Naiara , Martí Cristina , Torne Aureli , Ordi Jaume , del Pino Marta
Published: May 2019

Background

Allogenic hematopoietic stem cell transplantation (allo‐HSCT) is a common procedure in hematological disorders and is preceded by a conditioning regimen that usually includes busulfan. The immunosuppression caused by the conditioning regimen and graft‐versus‐host disease prophylaxis is associated with human papillomavirus (HPV) persistence and, consequently, with an increased risk of cervical cancer (CC) and squamous intraepithelial lesions (SILs)—the precursors of CC. A gynecological check‐up that includes CC screening is recommended in these patients.

Methods

All female recipients of allo‐HSCT undergo routine gynecological check‐up that includes CC screening. Cervical samples were obtained for liquid‐based cytology and HPV testing. Cytology smears were stained with the Papanicolaou (Pap) technique. A colposcopy evaluation was performed if any abnormal result in the screening tests was obtained.

Results

Among 15 women undergoing gynecological examination at 1 year after allo‐HSCT who had received a conditioning regimen that included busulfan, 4 (26.7%) showed atypical squamous cells in the Pap smear, suggesting high‐grade SIL. The abnormalities were identified from 136 to 271 days after allo‐HSCT. In all cases, HPV testing was negative, and colposcopy examination was normal. The cytological abnormalities regressed in 3 of the women after 1 year but persisted in 1 woman at day 382 after allo‐HSCT.

Conclusions

Treatment‐related atypia mimicking SIL is a common finding in allo‐HSCT recipients who have received busulfan, particularly in the first year after the procedure. However, atypical changes may persist for more than 1 year. Clinical information, HPV testing, and colposcopy examination are critical to prevent misdiagnosis and overtreatment in these patients.
Theoretical Identification of the Factors Governing the Reactivity of C−H Bond Activation by Non‐Heme Iron(IV)‐Oxo Complexes
Authors: Roy Lisa
Published: May 2019

Selective functionalization of C−H bonds provides a straightforward approach to a large variety of well‐defined derivatives. High‐valent mononuclear iron(IV)‐oxo complexes are proposed to carry out these C−H activation reactions in enzymes or in biomimetic syntheses. In this Minireview, we aim to highlight the features that delineate the distinct reactivity of non‐heme oxo‐iron(IV) motifs to cleave strong C−H bonds in hydrocarbons, primarily focusing on the hydrogen atom transfer (HAT) process. We describe how the structural and electronic properties of supporting ligands modulate the oxidative property of the iron(IV)‐oxo complexes. Furthermore, we highlight the decisive role played by spin‐state in these biomimetic reactions. We also discuss how tunneling and external perturbations like electric field influence the transfer of hydrogen atoms. Lastly, we emphasize how computations could work as a practical guide to sketch and develop synthetic models with greater efficacy.
Quantifying the Dynamics of Hematopoiesis by In Vivo IdU Pulse‐Chase, Mass Cytometry, and Mathematical Modeling
Authors: Erez Amir , Mukherjee Ratnadeep , Altan‐Bonnet Grégoire
Published: May 2019

We present a new method to directly quantify the dynamics of differentiation of multiple cellular subsets in unperturbed mice. We combine a pulse‐chase protocol of 5‐iodo‐2′‐deoxyuridine (IdU) injections with subsequent analysis by mass cytometry (CyTOF) and mathematical modeling of the IdU dynamics. Measurements by CyTOF allow for a wide range of cells to be analyzed at once, due to the availability of a large staining panel without the complication of fluorescence spillover. These are also compatible with direct detection of integrated iodine signal, with minimal impact on immunophenotyping based on the surface markers. Mathematical modeling beyond a binary classification of surface marker abundance allows for a continuum of cellular states as the cells transition from one state to another. Thus, we present a complete and robust method for directly quantifying differentiation at the systemic level, allowing for system‐wide comparisons between different mouse strains and/or experimental conditions. Published 2019. This article is a U.S. Government work and is in the public domain in the USA.
Accounting for ocean connectivity and hydroclimate in fish recruitment fluctuations within transboundary metapopulations
Authors: Hidalgo Manuel , Rossi Vincent , Monroy Pedro , Ser‐Giacomi Enrico , Hernández‐García Emilio , Guijarro Beatriz , Massutí Enric , Alemany Francisco , Jadaud Angelique , Perez José Luis , Reglero Patricia
Published: May 2019

Marine resources stewardships are progressively becoming more receptive to an effective incorporation of both ecosystem and environmental complexities into the analytical frameworks of fisheries assessment. Understanding and predicting marine fish production for spatially and demographically complex populations in changing environmental conditions is however still a difficult task. Indeed, fisheries assessment is mostly based on deterministic models that lack realistic parameterizations of the intricate biological and physical processes shaping recruitment, a cornerstone in population dynamics. We use here a large metapopulation of a harvested fish, the European hake (Merluccius merluccius), managed across transnational boundaries in the northwestern Mediterranean, to model fish recruitment dynamics in terms of physics‐dependent drivers related to dispersal and survival. The connectivity among nearby subpopulations is evaluated by simulating multi‐annual Lagrangian indices of larval retention, imports, and self‐recruitment. Along with a proxy of the regional hydroclimate influencing early life stages survival, we then statistically determine the relative contribution of dispersal and hydroclimate for recruitment across contiguous management units. We show that inter‐annual variability of recruitment is well reproduced by hydroclimatic influences and synthetic connectivity estimates. Self‐recruitment (i.e., the ratio of retained locally produced larvae to the total number of incoming larvae) is the most powerful metric as it integrates the roles of retained local recruits and immigrants from surrounding subpopulations and is able to capture circulation patterns affecting recruitment at the scale of management units. We also reveal that the climatic impact on recruitment is spatially structured at regional scale due to contrasting biophysical processes not related to dispersal. Self‐recruitment calculated for each management unit explains between 19% and 32.9% of the variance of recruitment variability, that is much larger than the one explained by spawning stock biomass alone, supporting an increase of consideration of connectivity processes into stocks assessment. By acknowledging the structural and ecological complexity of marine populations, this study provides the scientific basis to link spatial management and temporal assessment within large marine metapopulations. Our results suggest that fisheries management could be improved by combining information of physical oceanography (from observing systems and operational models), opening new opportunities such as the development of short‐term projections and dynamic spatial management.
Complexes Containing a Phenol–Platinum(II) Hydrogen Bond: Synthons for Supramolecular Self‐Assembly and Precursors for Hydridoplatinum(IV) Complexes
Authors: Behnia Ava , Fard Mahmood Azizpoor , Boyle Paul D. , Puddephatt Richard J.
Published: May 2019

The cycloneophylplatinum(II) complexes [Pt(CH2CMe2C6H4)(κ2‐NN′‐2‐C5H4NCH2‐NH‐R], R = 2‐C6H4OH, 1; R = 3‐C6H4OH, 2; R = 4‐C6H4OH, 3, and [Pt(CH2CMe2C6H4)(κ2‐NN′‐2‐C5H4NCH=N‐2‐C6H4OH)], 4, are reported. The structures of 1 and 4 each contain an intramolecular OH··Pt hydrogen bond, while complex 3 contains an intermolecular OH··Pt hydrogen bond and forms a new type of supramolecular polymer. In contrast, the complex [PtCl2(κ2‐NN′‐2‐C5H4NCH=N‐2‐C6H4OH)], 5, forms a dimer through intermolecular OH··ClPt hydrogen bonding. Reaction of complex 4 with HCl or HBr occurs by oxidative addition to give hydridoplatinum(IV) complexes [PtHX(CH2CMe2C6H4)(κ2‐NN′‐2‐C5H4NCH=N‐2‐C6H4OH)], 6, X = Cl; 7, X = Br. The sequential formation of isomers of these compounds is interpreted in terms of a proposed reaction mechanism.
The Development of Synthetic Routes to 1,1,n,n‐Tetramethyl[n](2,11)teropyrenophanes
Authors: Unikela Kiran Sagar , Merner Bradley L. , Ghasemabadi Parisa Ghods , Warford C. Chad , Qiu Christopher S. , Dawe Louise N. , Zhao Yuming , Bodwell Graham J.
Published: May 2019

A concise synthetic approach to 1,1,n,n‐tetramethyl[n](2,11)teropyrenophanes has been developed. It involves the construction of triply‐bridged pyrenophanes, during which the three bridges are installed successively using Friedel‐Crafts alkylation, Wurtz coupling and McMurry reactions. At the same time, the innate regiochemical preferences of pyrene toward electrophilic aromatic substitution are relied upon to control the substitution pattern. A cyclodehydrogenation reaction is then employed to generate the teropyrene system directly in a nonplanar conformation. The crystal structure of 1,1,7,7‐tetramethyl[7](2,11)teropyrenophane was determined and the teropyrene system was found to have an end‐to‐end bend angle of 177.9°.
Distribution of Experimentally Added Selenium in a Boreal Lake Ecosystem
Authors: Graves Stephanie D. , Liber Karsten , Palace Vince , Hecker Markus , Doig Lorne E. , Janz David M.
Published: May 2019

Human activities have increased the release of selenium (Se) to aquatic environments, but information about the trophic transfer dynamics of Se in Canadian boreal lake systems is limited. In the present study, Se was added as selenite to limnocorrals (2-m-diameter, 3000-L in situ enclosures) in a boreal lake in northwestern Ontario to reach nominal concentrations of 1 and 10 µg Se/L in triplicate each for 77 d, and 3 additional limnocorrals were controls with no Se added. Total Se concentrations were determined in water, sediment, periphyton, benthic macroinvertebrates, zooplankton, and reproductively mature female fathead minnows (Pimephales promelas; added on day 33) collected throughout (and at the end of) the exposure period. Mean measured water Se concentrations in the control, 1-, and 10-µg/L treatments were 0.12, 1.0, and 8.9 µg/L. At the end of exposure (day 77), enrichment functions ranged from 7772 L/kg dry mass in the 8.9-µg/L treatment to 23 495 L/kg dry mass in the 0.12-µg/L treatment, and trophic transfer factors for benthic macroinvertebrates ranged from 0.49 for Gammaridae to 2.3 for Chironomidae. Selenium accumulated in fathead minnow ovaries to concentrations near or above the current US Environmental Protection Agency criterion (15.1 µg/g dry mass for fish ovary/egg) in the 1.0- and 8.9-µg/L treatments, suggesting that, depending on aqueous Se speciation, such exposures have the potential to cause Se accumulation in fish to levels of concern in cold-water, boreal lake systems. Environ Toxicol Chem 2019;38:1954–1966. © 2019 SETAC.
Interactions of resveratrol with other phenolics and activity against food‐borne pathogens
Authors: Skroza Danijela , Šimat Vida , Smole Možina Sonja , Katalinić Višnja , Boban Nataša , Generalić Mekinić Ivana
Published: May 2019

The aim of this study was to investigate the antibacterial activity of individual phenolics and their binary mixtures with resveratrol against selected food‐borne pathogens. The antibacterial activity was quantified using the broth microdilution method by the determination of minimal inhibitory concentrations (MICs). Interactions between compounds in the binary phenolic mixtures were determined by calculating the fractional inhibitory concentration index (FICI). The influence of the number of OH groups in the phenols’ structure on their antibacterial activity was assessed by principal component analysis (PCA). The most effective compounds were flavone luteolin and flavonol rutin, while the weakest antimicrobial activity was observed for phenolic acid and flavan‐3‐ols (catechin and epicatechin). The synergistic effect (FICI ≤0.5) of equimolar mixture of resveratrol with kaempferol was confirmed against Staphylococcus aureus, Bacillus cereus, and Escherichia coli, while the mixture of rutin with resveratrol proved synergistic only against S. aureus. The increasing concentrations of resveratrol in the mixtures with kaempferol and rutin resulted in a loss of synergism which indicates that only selected phenolic mixtures, with optimal concentrations of their individual components, result in synergistic antibacterial activity. We did not find an association between total number of OH groups and antibacterial activity of either individual phenolics or their mixtures.
Spatiotemporal variability in hydrochemistry of shallow groundwater in a small pre‐alpine catchment: The importance of landscape elements
Authors: Kiewiet Leonie , von Freyberg Jana , van Meerveld H.J. (Ilja)
Published: May 2019

Topography and landscape characteristics affect the storage and release of water and, thus, groundwater dynamics and chemistry. Quantification of catchment scale variability in groundwater chemistry and groundwater dynamics may therefore help to delineate different groundwater types and improve our understanding of which parts of the catchment contribute to streamflow. We sampled shallow groundwater from 34 to 47 wells and streamflow at seven locations in a 20‐ha steep mountainous catchment in the Swiss pre‐Alps, during nine baseflow snapshot campaigns. The spatial variability in electrical conductivity, stable water isotopic composition, and major and trace ion concentrations was large and for almost all parameters larger than the temporal variability. Concentrations of copper, zinc, and lead were highest at sites that were relatively dry, whereas concentrations of manganese and iron were highest at sites that had persistent shallow groundwater levels. The major cation and anion concentrations were only weakly correlated to individual topographic or hydrodynamic characteristics. However, we could distinguish four shallow groundwater types based on differences from the catchment average concentrations: riparian zone‐like groundwater, hillslopes and areas with small upslope contributing areas, deeper groundwater, and sites characterized by high magnesium and sulfate concentrations that likely reflect different bedrock material. Baseflow was not an equal mixture of the different groundwater types. For the majority of the campaigns, baseflow chemistry most strongly resembled riparian‐like groundwater for all but one subcatchment. However, the similarity to the hillslope‐type groundwater was larger shortly after snowmelt, reflecting differences in hydrologic connectivity. We expect that similar groundwater types can be found in other catchments with steep hillslopes and wet areas with shallow groundwater levels and recommend sampling of groundwater from all landscape elements to understand groundwater chemistry and groundwater contributions to streamflow.
Cancer of unknown primary: Incidence rates, risk factors and survival among adolescents and young adults
Authors: Pavlidis Nicholas , Rassy Elie , Smith‐Gagen Julie
Published: May 2019

Cancer of unknown primary (CUP) is a clinical challenge especially when it occurs in adolescents and young adults (AYA), aged 15–39 years, due to the sparse data in this population. The available data has not described the population‐based epidemiological features of CUP among AYA. Therefore, we collected patient information from the Surveillance, Epidemiology and End Results (SEER) registry, 1990–2015. Age, gender, ethnic, five pathological classification groups were assessed along with an aggregate level socioeconomic status (SES) index and population density at the county level. Incidence rates, modeled relative risks and survival of AYA patients with CUP were assessed. Among 2,480 AYA patients, 907 met the definition of standard pathology classifications. The majority of AYA patients with CUP had a neuroendocrine, squamous cell and poorly differentiated carcinomas with 0.4 cases per 1,000,000 population. AYA living in areas with the highest SES level had the highest risks of CUP; adjusted relative risks (ARR) of 1.17 (95% CI 1.0–1.4) and 1.99 (95% CI 1.5–2.6), respectively. AYA living in nonmetropolitan areas had a lower risk of CUP (ARR = 0.16; 95% CI 0.1–0.2). The incidence of differentiated neoplasms has been decreasing slower than undifferentiated neoplasms since the early 1990s. The median overall survival (OS) was 11 months (95% CI 9–13 months) with squamous CUP having the longest median OS 16 years (95% CI 3–24 years). In conclusion, this analysis answers several gaps in the knowledge of CUP among AYA and provides a platform to better understand this disease and its management within this group.
Laparoscopic‐assisted surgery for liposarcoma of the spermatic cord extending to the retroperitoneal cavity through the internal inguinal ring
Authors: Ochi Atsuhiko , Toki Sari , Vanichakarn Dollacha , Suzuki Koichiro , Kitagawa Yasuhide , Abe Hirokazu
Published: May 2019

Introduction

Liposarcoma of the spermatic cord is a rare disease, reportedly treated with radical high orchiectomy. However, laparoscopic‐assisted surgery for spermatic cord liposarcoma extending to the retroperitoneal cavity through the internal inguinal ring has not yet been reported.

Case presentation

A 78‐year‐old man had a spermatic cord tumor that extended to the retroperitoneal cavity through the internal inguinal ring and invaded the abdominal wall muscles. We performed laparoscopic‐assisted surgery and successfully separated the tumor from the contiguous organs and vessels. The tumor was resected en bloc with abdominal wall muscles, and a muscular defect was repaired with a left tensor fascia lata muscle flap. Pathological analysis revealed a well‐differentiated liposarcoma with negative surgical margins. There was no recurrence at 1 year post‐surgery.

Conclusion

Laparoscopic‐assisted surgery is a feasible and minimally invasive procedure for treating liposarcoma of the spermatic cord extending to the retroperitoneal cavity through the internal inguinal ring.
Low‐dimensional nanomaterial/Si heterostructure‐based photodetectors
Authors: Tian Wei , Sun Haoxuan , Chen Liang , Wangyang Peihua , Chen Xinrui , Xiong Jie , Li Liang
Published: May 2019

Due to its excellent electrical and optical features, silicon (Si) is highly attractive for photodetector applications. The design and fabrication of low‐dimensional semiconductor/Si hybrid heterostructures provide a great platform for fabricating high‐performance photodetectors, thereby overcoming the inherent limitations of Si. This review focuses on state‐of‐the‐art Si heterostructure‐based photodetectors. It starts with the introduction of three different device configurations, that is, photoconductors, photodiodes, and phototransistors. Their working mechanisms and relative pros and cons are introduced, and the figures of merit of photodetectors are summarized. Then, we discuss the device physics/design, photodetection performance, and optimization strategies for Si‐based photodetectors. Finally, future challenges in the photodetector applications of Si‐based hybrid heterostructures are discussed.