bluuebunny/crossref_metadata_2025 huggingface dataset:
Knowledge and Attitudes towards Healthcare Information Technology of the Rural Health Workers in SAMARICA, Occidental Mindoro, Philippines
Authors: Sanqui Rommel C. , Declaro-Ruedas Mary Yole Apple
Published: March 2020

The descriptive research aims to determine the socio-demographic characteristics of the healthcare providers, the health workers’ knowledge of and attitudes towards computer applications and the relationship between socio-demographic characteristics of the healthcare providers and their knowledge of and attitudes towards computer applications.

The study was conducted in the Rural Health Units of San Jose, Magsaysay, Rizal & Calintaan, Occidental Mindoro from March 2017 to June 2018. The 51 health workers were purposively selected as respondents of the study. Survey and interview were used to gather the data needed. Descriptive statistics and Pearson Moment Correlation were used to analyse the gathered data.

Results shows the healthcare providers are female, young, college graduate, and have long work experience in the maternal and newborn care section and had assisted the rural health doctor during consultations. The healthcare providers have “high” level of knowledge on computer and its applications and had expressed “positive” attitudes towards the use of computers in their work.

Further, only age has a significant relationship with the healthcare providers’ knowledge of and attitude towards computer applications.
In-vitro Anti-cancer Activity of Endophytic Fungi Isolated from Ziziphus mauritiana in Cervical Cancer Cell Line
Authors: Sheeba H. , Ali M. Syed , Anuradha V.
Published: March 2020

Aim: The fungal crude extract of Trichoderma viride isolated from the medicinal plant of Ziziphus mauritiana was investigated for anti-cancer activity against HeLa cell line.

Place and Duration of Study: The entire research work was done in the Department of Biotechnology, Mohammed Sathak College of Arts and Science, Chennai, India and Stellixir Biotech Pvt Ltd, Bangalore, Karnataka, between April 2019 to June 2019.

Methodology: In MTT assay, cells were seeded in 96 well plates with concentrations of 2.5, 25, 50, 100, 200 μl/ml of fungal bioactive compound and the absorbance was measured at 570 nm. Apoptosis was carried out via flow cytometry using control Camptothecin and fungal extract concentration. Subsequently, cell cycle arrest was determined by 400 μl PI/RNAse staining buffer and further analyzed using PI solutions by flow cytometry. Finally, the damage of the nucleus observed under a Fluorescent microscope using DAPI staining.

Results: MTT assay revealed an obtained fungal compound showed IC50 concentration against the HeLa cells at 23.57 μg/ml. Apoptosis analysis suggested under the M1 population the viable cells are low in mean Annexin V-FITC while M2 is the apoptotic cells have taken up the Annexin V-FITC and high in mean Annexin V-FITC fluorescence intensity. The cell cycle arrest has been noted by decreasing the percentage of arrest in the G0/G1 phase and increased in S and G2/M phase compared to controls. In the course of DAPI staining, it has been understood that IC50 23.57 μg/ml has an efficient nuclear dent after the treatment.

Conclusion: In-vitro studies revealed that Trichoderma viride has promising cytotoxicity effect against the HeLa cell line. Hence the bioactive compounds of 3-beta-hydroxy urs-12-en-28-oic acid which is responsible for the treatment of cervical cancer. However in-vivo experiments need to be conceded out for further studies.
The 2019 Novel Coronavirus Outbreak: Current Crises, Controversies and Global Strategies to Prevent a Pandemic
Authors: Enitan Seyi Samson , Ibeh Isaiah Nnana , Oluremi Adeolu Sunday , Olayanju Ayodeji OluSola , Itodo Grace Eleojo
Published: March 2020

The 2019 novel coronavirus (2019-nCov) has been implicated in the outbreak of an uncommon pneumonia in Chinese City of Wuhan, Hubei Province first reported in late December 2019. Since then, infection has spread to other Chinese cities, as well as internationally, threatening to trigger a pandemic. On January 30 2020, the World Health Organization (WHO) in an effort to slow down the global spread of the virus declared the outbreak, “A global public health emergency of international concern”. As at the time of this review, there were more than 31 000 confirmed cases and 638 deaths reported globally. Controversies exist on the origin of the virus with diverse views. The swift rise in morbidity and mortality rate of the virus has caused widespread alarm in China and other parts of the world. This review is aimed at providing relevant information on the possible origin of the virus, its mode of transmission, associated risk factors, existing controversies, consequences of the current trend and control interventions required to halt the widespread of the new coronavirus outbreak.
Isolation of Bacteria with Potential of Producing Extracellular Enzymes (Amylase, Cellulase and Protease) from Soil Samples
Authors: Fasiku Samuel Adedayo , Ogunsola Olaolu Fikayo , Fakunle Adeola , Olanbiwoninu Afolake Atinuke
Published: March 2020

Introduction: Amylase, cellulase and protease are known for hydrolyzing starch, cellulose and protein respectively and these enzymes can be produced by microorganisms. A single bacterium with potential of producing amylase, cellulase and protease will be an organism of high industrial value.

Aims: This work aimed at isolating bacteria that will be able to produce three extracellular enzymes (amylase, cellulase and protease).

Methodology: Soil samples were collected from eight different locations within Ajayi Crowther University, Oyo Town, Nigeria. Bacteria were isolated from these soil samples and were identified using morphological and biochemical characteristics. Isolated bacteria were screened for their ability to produce amylase, cellulase and protease on plate and enzymes’ relative activities on plate were determined.

Results: Forty two bacteria were isolated from soil samples and identified to belong to the Genera Bacillus (30), Enterobacter (6), Klebsiella (3) and Staphylococcus (3). Eight (19%), Eleven (26%) and Nineteen (45%) out of 42 isolated bacteria were able to produce amylase, cellulase and protease on plate with relative activities ranging from 1.25 – 2.88, 1.39 – 4.50 and 1.13 – 5.17 respectively. All the eight amylolytic isolates (Bacillus species (5) and Enterobacter species (3)) were able to produce the three enzymes (amylase, cellulase and protease).

Conclusion: Eight bacteria with ability to produce three enzymes (amylase, cellulase and protease) were isolated from soil samples and could be further employed in enzyme-producing industries.
Sensitivity Analysis of the Quadratic Discriminant Function for Predicting Pregnancy Outcomes
Authors: Asosega Killian Asampana , Adedia David , Adebanji Atinuke O.
Published: March 2020

The prevalence rate of stillbirth is ten times higher in developing countries relative to developed countries with a 2016 rate of 18 percent in Ghana. This study employed the Quadratic Discriminant Function for discriminating and classifying of pregnancy outcomes based on some predictors. The study further examined the sensitivity of the Quadratic Discriminant Function in predicting pregnancy outcomes with variations in the training and test samples of deliveries recorded in a hospital in Accra, Ghana. The study considered the scenarios; 50:50, 60:40, 70:30 and 75:25 ratios of training sets to testing sets. Predictor variables on both maternal factors (maternal age, parity and gravida) and fetus variables (weight at birth and gestational period) were all statistically significant (P < .01) in discriminating between live birth and stillbirth. Results showed that maternal age had a negative effect on the live birth outcomes, while parity, gravida, gestational period and fetus weight recorded positive effects on live birth outcomes. The 75:25 ratio outperformed the other ratios in discriminating between live and stillbirth based on the Actual Error Rate of 7.28% compared to 7.81%, 12.14% and 13.79% for the 50:50, 70:30 and 60:40 ratios respectively whereas, the receiver operating characteristic curve shows the 70:30 (AUC= 0.9233) ratio outperformed the others. The study recommend the use of either the 70:30 or 75:25 training to test ratios for classification and discrimination related problems. Moreover, further research to establish the power of the respective training to test sample ratios with other statistical classification tools and more socio-economic variables can be considered.
Linkages between External Reserves and Economic Performance in Nigeria, 1981-2018: Bounds Test and ARDL Approaches
Authors: Ojiako Ifeanyi A.
Published: March 2020

Aims: This study seeks to explore a two-way relationship between Nigeria’s economic performance, measured by the GDP, and her stock of foreign reserves over time.

Study Design: It uses secondary data - documented time series of Nigeria’s gross domestic product (GDP) and foreign exchange reserves (FER) – collected from various volumes of the Central Bank of Nigeria (CBN) Statistical Bulletin. The annual time series data cover a period of 38 years, from 1981-2018.

Methodology: The time series properties of the variables were verified using the Augmented Dickey-Fuller (ADF) unit roots’ test procedure. Also, the Bounds test technique was used to test for cointegration while the autoregressive distributed-lag (ARDL) and error correction models were estimated to analyze short- and long-run relationships between the variables. Relevant diagnostic tests were carried out to validate the resultant model estimates.

Results: Results of unit roots’ test reveal both GDP and foreign reserves as I(1) series. Bounds test for the GDP model revealed an observed F-statistic (.421) that is less than the critical lower bound F-statistic (4.94) at P=.05 and cointegrating relationship was not confirmed. However, Bounds test for the foreign reserves revealed an observed F-statistic (6.445) lager than the critical upper bound F-statistic (5.73) at P=.05 and cointegration was established leading to specification of a long-run error correction model (ECM). Result of ARDL model estimation shows that only one-year-lag of GDP was significant (P=.05) and positive in explaining variations in the current GDP. Previous year’s values of both GDP and foreign reserves have positive influence on the long-run foreign exchange with over 81.8% explanatory power. The adjustment coefficient of the error correction equation is highly significant (P=.001) with the desired negative sign, implying that previous periods’ errors are correctable by adjustments in the subsequent periods, and convergence is attainable. Granger-Causality test result revealed a unidirectional causality that runs from GDP to the external reserves.

Conclusion: The study establishes a long-run relationship between stock of foreign reserves and economic performance in Nigeria. The finding corroborates the view that a booming economy has the propensity to attract foreign direct investment thereby boosting the stock of the country’s foreign reserves. To attract more FDI in the critical sectors of the Nigerian economy, the government should create enabling and investment-friendly environment, implement policies and programmes capable of amplify ease-of-doing-business, and boost investors’ confidence in the economy.
Preoperative CT Colonography in Partially Obstructed Colon Cancer, and its Benefit in Surgical Management
Authors: Zubaidi A. , Al-Kharji H. , Abdulla M. , Al-Obeed O. , Al-Khayal K. , El-Sharkawy M. , Al Boukai A.
Published: March 2020

Background and aims

Stenotic colorectal carcinoma impending obstruction (SCRCIO) is a frequently encountered situation complicating 10% to 19% of colorectal cancers. This group of patients cannot undergo complete colonoscopic assessment. The aim of this study is to examine the accuracy of computed tomographic colonography (CTC) as preoperative assessment of the colon of patients with SCRCIO and to measure the effect on the surgical decision.

Materials and methods

This was a prospective study, from September 2009 through December 2012, on a cohort of symptomatic adult patients with SCRCIO. Patients underwent CTC evaluation after failed conventional colonoscopy (CC), followed by a follow-up endoscopic examination 3–6 months after surgical treatment.

Results

Twenty-nine patients with an average age of 55 were included in this study; the majority of stenotic masses were located in the sigmoid colon. Preoperative CTC matched the colonoscopy location of the stenotic masses (17 patients). CTC sensitivity per stenotic lesion detection was 100% and 92.5% for the location. Sensitivity was 100% for synchronous lesions, and CTC changed surgical plan in 17% of the patients.

Conclusion

CTC presented high sensitivity, specificity and accuracy for the identification of colonic lesions of any size. Preoperative CTC may possibly become the diagnostic procedure of choice for SCRCIO patients. It enables surgeons to evaluate the entire colon, minimizing the possibility of surgical re-intervention if there is a finding of synchronous neoplastic lesions at postoperative follow-up endoscopy.
Clinical Significance of Soluble Fibrin in Coagulopathy Caused by Highly Invasive Surgery
Authors: Satoh Hajime , Kushihata Fumiki , Hatano Masahide , Watanabe Jota , Takada Yasutsugu
Published: March 2020

Background

The clinical use of soluble fibrin (SF) as a coagulation marker is increasing. However, its diagnostic role in critical coagulopathy during invasive abdominal surgery has not been examined.

Methods

In the present study we evaluated changes in SF and other conventional markers, and we performed statistical examination of risk factors in disseminated intravascular coagulation (DIC). A total of 44 highly invasive surgeries (segmental hepatectomy or more, 28; pancreaticoduodenectomy, 9; distal pancreatectomy, 5; and splenectomy, 2) were included. After excluding 7 patients who did not develop DIC, 37 patients were classified into 2 groups: the SIRS-associated coagulopathy (SAC) group, in which SAC remained after surgery (n = 16), and the DIC group, which developed DIC (n = 21). All patients received a diagnosis of SAC on postoperative day 1 (POD1) and DIC on POD2.

Results

Multivariate analysis revealed significant differences only in the SF level and fibrinogen degradation product (FDP; odds ratios, 14.4 and 7.8). A prediction formula was then prepared based on the β value: P = 1 / [1 + exp {–(2.665 × SF + 2.049 × FDP – 1.309)}]. The sensitivity and specificity of the prediction formula were 71% and 94%, respectively.

Conclusions

These results showed that the risk factors in the DIC group were SF and FDP on POD1, with SF being the stronger risk factor. Operative stress can be quantified using the SF level on POD1, enabling more specific perioperative management from the perspective of postoperative coagulopathy control.
Prognostic Performance of Three Lymph Node Staging Systems in Patients After D2 Lymphadenectomy for Gastric Cancer
Authors: Huang Ze-Ping , Zhang Wen-Jun , Wang Zi-Xian , Liu Hai-Peng , Zeng Xiang-Ting , Chen Kang , Li Mei , Chen Zhao-Feng , Zhang Dong-Sheng , Chen Xiao
Published: March 2020

Background

Accurate staging of lymph node (LN) status is essential for predicting prognosis in patients with gastric cancer. Recent proposals suggest that lymph node ratio (LNR) and log odds of metastatic lymph nodes (LODDS) may have superior accuracy in predicting survival by minimizing stage migration. The aim of the present study was to compare the prognostic performances of the UICC (pN), LNR and LODDS staging systems and incorporate the optimal system into a nomogram for predicting individual survival in patients with resectable gastric cancer.

Methods

The study cohort comprised of 423 patients who had undergone D2 lymphadenectomy. The discriminatory powers of the different LN staging systems were compared using the concordance index (C-index). The optimal system was incorporated into a prognostic nomogram with other independent prognosticators, and bootstrap validation was performed.

Results

When LN status was assessed as a continuous variable, the LNR system (C-index: 0.712) was superior to pN (C-index: 0.695) and LODDS (C-index: 0.704). Age, LNR, and preoperative serum CA 19-9 and CA 125 were incorporated into a nomogram for predicting 2-year overall survival. Internal validation of the nomogram revealed good predictive abilities, with a bootstrap-corrected concordance index of 0.704.

Conclusion

Overall, LNR was the optimum predicator of survival in patients with resectable gastric cancer on the basis of LN status. LNR was incorporated into a nomogram along with age and preoperative serum CA 19-9 and CA 125. Internal validation confirmed the predictive ability of this nomogram.
Emergency Surgery and Male Gender Are Risk Factors of Postoperative Delirium After General or Gastrointestinal Surgery in Elderly Patients: A Multicenter Cohort Study
Authors: Yamamoto Kazuyoshi , Shimakawa Noriko , Mizumoto Takao , Shiroyama Kazuhisa , Shichino Tsutomu , Yuzawa Kenji , Kataoka Masato , Horiuchi Tetsuya , Teshima Shin , Shibasaki Shinichi , Hirao Motohiro
Published: March 2020

Objective

The aim of this study was to investigate the incidence and risk factors of postoperative delirium (PD) in elderly patients after general or gastrointestinal surgery.

Summary of background data

Societies worldwide are rapidly aging, and the number of surgeries in elderly patients has been increasing. PD, which adversely influences postoperative course, has thus become more common.

Methods

The Surgery and Anesthesia Network Group of the National Hospital Organization in Japan conducted this retrospective cohort study of patients older than 70 years of age who underwent general or gastrointestinal surgery.

Results

A total of 219 patients from 9 participating institutes underwent surgery between July 2013 and August 2014. We excluded 2 patients who died within 2 weeks after surgery. Of the remaining 217 cases, 31 (14.3%) developed PD. These patients were older (80 versus 76 years, P = 0.013), more likely to be male (74.2 versus 54.8%, P = 0.039), and had higher American Society of Anesthesia Physical Status scores than those without PD. Emergency surgery was more common than elective surgery in the PD group (41.9 versus 10.2%, P < 0.0001). Multivariate analysis showed that male gender (odds ratio, 3.31; 95% confidence interval, 1.32 to 9.39; P = 0.0098) and emergency surgery (odds ratio, 7.47; 95% confidence interval, 2.79 to 20.83; P < 0.0001) were independent risk factors of PD.

Conclusions

The incidence of PD was high in male patients and those undergoing emergency surgery. Effective interventions in these groups will be necessary to improve treatment outcomes in elderly patients.
Assessing Surgeons' Preferences in the Management of Fistula In Ano
Authors: Zahid Assad , Byrne Chris , Solomon Michael J , Young Christopher J.
Published: March 2020

Background

Fistula in ano is a common condition treated by surgeons worldwide. Despite this, there is a paucity of high-quality data to aid decision-making. Hence, management presents a difficult and frustrating dilemma for the treating surgeon.

Methods

A prospective regional survey was sent to all members of General Surgeons Australia. Questions regarding surgeon demographics, patient evaluation, perianal abscess, and simple and complex fistula in ano were presented.

Results

Equipoise exists in the management of fistula in ano among general surgeons. This was noted in the management of simple and complex fistula in ano.

Conclusion

Because of the uncertainty in certain clinical scenarios and a paucity of high-quality randomized controlled trials on the management of fistula in ano, evidence-based practice is a challenge to the treating surgeon.
Nutritional Assistance by Software Improves Surgical Outcomes of Elective Colorectal Surgery
Authors: Ouaissi Mehdi , di Costanzo Jacques , Boiron Laurence , Hankard Regis , Guilbaud Théophile , Mege Diane , Maignan Aurelie , Rossi Caroline , Frasconi Cecilia , Le Huu Nho Remy , Anderson Loundou , Pirro Nicolas , Iannelli Antonio , Sielezneff Igor
Published: March 2020

Objective

The present study analyzes nutrition support in a group of patients undergoing colorectal surgery managed by nutritional requirement software compared to a group of consecutive patients undergoing colorectal surgery with conventional nutrition

Materials and Methods

A total of 485 patients were treated between January 2000 and January 2013 with colorectal resection. Outcomes (mortality, morbidity according to Clavien classification, length of hospital stay, type of colorectal disease) in a group of patients who received nutrition support through software (SG) were compared to those in a previous series, control group (CG) with conventional nutrition support

Results

Of the patients, 59.6% were men and the median age of the population was 68.2 years (range, 19–95 years), with no difference between the 2 groups. There were significantly more malnourished patients in the SG group (SG 63.8% versus 45.2% CG; P < 0.0001). The overall mortality was 2.1% lower in the SG group, but without a significant difference (SG 0.7% versus 2.7% CG). There were more severe stage III to IV complications according to Clavien classification in the SG group (SG 10.7 GC versus 17% NS), with significantly greater collections (SG 8% versus 16.9% CG; P = 0.015) and greater anastomotic leaks (SG 4% versus 13.9% CG; P < 0.001). The median hospital stay was lower in the SG group (SG 12 days versus 15 days CG; P = 0.049).

Conclusion

The proposed software could contribute to optimizing the strategy of nutritional support in hospitalized patients.
Percutaneous Radiofrequency Ablation With a Multiple-Electrode Switching System for Medium-Sized Hepatocellular Carcinomas
Authors: Tan Tunhua , Li Xuesong , Wang Qiang , Li Kun , Ma Kuansheng
Published: March 2020

Objective

This study aimed to retrospectively evaluate the safety and short-term therapeutic efficacy of radiofrequency ablation (RFA) with a multiple-electrode switching system (MESS) to treat medium-sized (3.1–5.0 cm) hepatocellular carcinomas (HCCs).

Summary of Background Data

Conventional monopolar RFA is limited in achieving local control for tumors larger than 3 cm. Therefore, MESS-RFA was developed, and it can create a sufficiently large ablation volume, including the target tumor and a 5- to 10-mm safety margin in medium-sized tumors.

Methods

We performed a total of 168 RFAs with a MESS for 166 patients. The patients were treated under ultrasonographic guidance by a percutaneous switching system RFA with a multichannel RF generator and 2 or 3 internally cooled electrodes. Technical effectiveness, local progression, and remote recurrence of HCC were determined.

Results

For the 166 isolated HCC tumors, the complete ablation rate of MESS-RFA was 98.79% (164 of 166). Mean ablation time per procedure was 12.33 ± 3.01 minutes; mean ablation diameter was 5.79 ± 0.61 cm. The complication rate was 2.41%. During follow-up (averaging 16.54 months), local tumor progression occurred in 15 of 166 patients (9.03%) with technical effectiveness, whereas new HCCs were detected in 40 of 166 patients (24.09%). Multivariate analyses revealed that local tumor progression was only associated with serum α-fetoprotein levels above 100 ng/mL as a risk factor.

Conclusion

MESS-RFA for achieving sufficient ablation volume is safe and efficient. This method also showed relatively successful therapeutic effectiveness on short-term follow-up in the treatment of medium-sized HCCs.
Changes in Medial Meniscal Three‐Dimensional Position and Morphology As Predictors of Knee Replacement in Rapidly Progressing Knee Osteoarthritis: Data From the Osteoarthritis Initiative
Authors: Roth Melanie , Emmanuel Katja , Wirth Wolfgang , Kwoh C. Kent , Hunter David J. , Hannon Michael J. , Eckstein Felix
Published: March 2020

Objective

To assess whether quantitative changes in the meniscus predict progression from early knee osteoarthritis (OA) to knee replacement (KR).

Methods

A nested case–control study was conducted among Osteoarthritis Initiative participants: all 35 case knees with baseline Kellgren/Lawrence (K/L) grade ≤2 that had KR between 36 and 60 months were matched 1:1 by age, sex, and baseline K/L grade to 35 control knees without subsequent KR. Quantitative 3‐dimensional medial meniscus position and morphologic measures were determined from magnetic resonance imaging at the visit just before KR and 2 years before. Paired t‐tests and case–control odds ratios (ORs, standardized per SD of change in controls) were used to compare changes between groups.

Results

Cases (52% women, age 65 ± 7 years, body mass index [BMI] 30 ± 4 kg/m2, K/L grades 0/1/2: 5/8/22 participants, respectively) and controls (52% women, age 64 ± 7 years, BMI 30 ± 5 kg/m2, K/L grades 0/1/2: 9/4/22 participants, respectively) were similar. Compared to control knees, KR case knees displayed longitudinal changes, specifically, a decrease in tibial plateau coverage, an increase in meniscal extrusion, and a decrease in meniscal width. The odds for KR increased with greater reduction in the percentage of tibial plateau coverage (OR 2.28 [95% CI confidence interval (95% CI) 1.43, 3.64]), a greater increase in maximal extrusion (OR 1.40 [95% CI 1.12, 1.75]), and a greater reduction of mean meniscal width (OR 2.01 [95% CI 1.23, 3.26]). The odds for KR increased with medial compartment cartilage thickness loss (OR 2.86 [95% CI 1.51, 5.41]) for comparison.

Conclusion

Quantitative measures of meniscal position and morphology are associated with subsequent KR in knees with rapidly progressing knee OA. These findings show that structural changes of the meniscus are related to an important clinical and economic outcome of knee OA.
Ultrathin Polydopamine Films with Phospholipid Nanodiscs Containing a Glycophorin A Domain
Authors: Marchesi D'Alvise Tommaso , Harvey Sean , Hueske Lisa , Szelwicka Jolanta , Veith Lothar , Knowles Tuomas P. J. , Kubiczek Dennis , Flaig Carolin , Port Fabian , Gottschalk Kay‐E. , Rosenau Frank , Graczykowski Bartlomiej , Fytas George , Ruggeri Francesco S. , Wunderlich Katrin , Weil Tanja
Published: March 2020

Cellular membranes have long served as an inspiration for nanomaterial research. The preparation of ultrathin polydopamine (PDA) films with integrated protein pores containing phospholipids and an embedded domain of a membrane protein glycophorin A as simplified cell membrane mimics is reported. Large area, ultrathin PDA films are obtained by electropolymerization on gold surfaces with 10–18 nm thickness and dimensions of up to 2.5 cm2. The films are transferred from gold to various other substrates such as nylon mesh, silicon, or substrates containing holes in the micrometer range, and they remain intact even after transfer. The novel transfer technique gives access to freestanding PDA films that remain stable even at the air interfaces with elastic moduli of ≈6–12 GPa, which are higher than any other PDA films reported before. As the PDA film thickness is within the range of cellular membranes, monodisperse protein nanopores, so‐called “nanodiscs,” are integrated as functional entities. These nanodisc‐containing PDA films can serve as semi‐permeable films, in which the embedded pores control material transport. In the future, these simplified cell membrane mimics may offer structural investigations of the embedded membrane proteins to receive an improved understanding of protein‐mediated transport processes in cellular membranes.
Tunable Fano‐Resonant Metasurfaces on a Disposable Plastic‐Template for Multimodal and Multiplex Biosensing
Authors: Ahmed Rajib , Ozen Mehmet Ozgun , Karaaslan Merve Goksin , Prator Cecilia A. , Thanh Cassandra , Kumar Shreya , Torres Leonel , Iyer Nikita , Munter Sadie , Southern Sarka , Henrich Timothy J. , Inci Fatih , Demirci Utkan
Published: March 2020

Metasurfaces are engineered nanostructured interfaces that extend the photonic behavior of natural materials, and they spur many breakthroughs in multiple fields, including quantum optics, optoelectronics, and biosensing. Recent advances in metasurface nanofabrication enable precise manipulation of light–matter interactions at subwavelength scales. However, current fabrication methods are costly and time‐consuming and have a small active area with low reproducibility due to limitations in lithography, where sensing nanosized rare biotargets requires a wide active surface area for efficient binding and detection. Here, a plastic‐templated tunable metasurface with a large active area and periodic metal–dielectric layers to excite plasmonic Fano resonance transitions providing multimodal and multiplex sensing of small biotargets, such as proteins and viruses, is introduced. The tunable Fano resonance feature of the metasurface is enabled via chemical etching steps to manage nanoperiodicity of the plastic template decorated with plasmonic layers and surrounding dielectric medium. This metasurface integrated with microfluidics further enhances the light–matter interactions over a wide sensing area, extending data collection from 3D to 4D by tracking real‐time biomolecular binding events. Overall, this work resolves cost‐ and complexity‐related large‐scale fabrication challenges and improves multilayer sensitivity of detection in biosensing applications.
Fano Resonance in Artificial Photonic Molecules
Authors: Cao Guangtao , Dong Shaohua , Zhou Lei‐Ming , Zhang Qing , Deng Yan , Wang Cong , Zhang Han , Chen Yang , Qiu Cheng‐Wei , Liu Xinke
Published: March 2020

The spectral signatures of chemical molecules are dependent on the hybridization of electronic states. The artificial photonic molecules formed by structured optical microcavities, exhibiting Fano features with sharp asymmetric line shape and strong field enhancement, hold various potential applications in sensors, optical switches, lasing spasers, optical diodes, etc. To design high‐performance photonic devices, it is of great importance to gain the formation and modulation mechanisms of Fano resonance in various artificial photonic molecules. This review is focused on the Fano resonance in artificial photonic molecules. It starts by discussing the properties of Fano resonance, followed by a detailed discussion of the coupled oscillator model and coupled mode theory that could reveal the underlying mechanisms. Then, different types of photonic molecules for realizing Fano resonance are presented, and several representative exciting applications are introduced. Finally, a summary and a brief outlook on challenges are discussed for Fano resonance in artificial photonic molecules.
A Cleavage‐Modification‐Reassembly Process Catalyzed by Rhodium and Brønsted Acid for the Synthesis of Multi‐Substituted Anilines
Authors: Liu Xiangrong , Xiao Guolan , Xu Xinfang , Kang Zhenghui , Zhang Dan , Hu Wenhao
Published: March 2020

A synergistic rhodium‐ and Brønsted acid‐ catalyzed reaction of quinone imine ketals with diazo compounds to access multi‐substituted anilines is presented here. This reaction takes place through a process involving C−O bond cleavage, modification of the leaving alcoholic fragment, and selective reassembly of the reactive fragments. Moderate enantioselectivities are achieved when a chiral 1,1’‐bi(2‐naphthol)‐based phosphoric acid is used.

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Hybrid Perovskite‐Organic Flexible Tandem Solar Cell Enabling Highly Efficient Electrocatalysis Overall Water Splitting
Authors: Li Zhen , Wu Shengfan , Zhang Jie , Lee Ka Chun , Lei Hang , Lin Francis , Wang Zilong , Zhu Zonglong , Jen Alex K. Y.
Published: March 2020

Perovskite‐organic tandem solar cells are attracting more attention due to their potential for highly efficient and flexible photovoltaic device. In this work, efficient perovskite‐organic monolithic tandem solar cells integrating the wide bandgap perovskite (1.74 eV) and low bandgap organic active PBDB‐T:SN6IC‐4F (1.30 eV) layer, which serve as the top and bottom subcell, respectively, are developed. The resulting perovskite‐organic tandem solar cells with passivated wide‐bandgap perovskite show a remarkable power conversion efficiency (PCE) of 15.13%, with an open‐circuit voltage (Voc) of 1.85 V, a short‐circuit photocurrent (Jsc) of 11.52 mA cm−2, and a fill factor (FF) of 70.98%. Thanks to the advantages of low temperature fabrication processes and the flexibility properties of the device, a flexible tandem solar cell which obtain a PCE of 13.61%, with Voc of 1.80 V, Jsc of 11.07 mA cm−2, and FF of 68.31% is fabricated. Moreover, to demonstrate the achieved high Voc in the tandem solar cells for potential applications, a photovoltaic (PV)‐driven electrolysis system combing the tandem solar cell and water splitting electrocatalysis is assembled. The integrated device demonstrates a solar‐to‐hydrogen efficiency of 12.30% and 11.21% for rigid, and flexible perovskite‐organic tandem solar cell based PV‐driven electrolysis systems, respectively.
Piezoelectric Energy Harvesting from a Ferroelectric Hybrid Salt [Ph3MeP]4[Ni(NCS)6] Embedded in a Polymer Matrix
Authors: Vijayakanth Thangavel , Ram Farsa , Praveenkumar Balu , Shanmuganathan Kadhiravan , Boomishankar Ramamoorthy
Published: March 2020

Organic–inorganic hybrid ferroelectrics are an exciting class of molecular materials with promising applications in the area of energy and electronics. The synthesis, ferroelectric and piezoelectric energy harvesting behavior of a 3d metal ion‐containing A4BX6 type organic–inorganic hybrid salt [Ph3MeP]4[Ni(NCS)6] (1) is now presented. P‐E hysteresis loop studies on 1 show a remnant ferroelectric polarization value of 18.71 μC cm−2, at room temperature. Composite thermoplastic polyurethane (TPU) devices with 5, 10, 15 and 20 wt % compositions of 1 were prepared and employed for piezoelectric energy harvesting studies. A maximum output voltage of 19.29 V and a calculated power density value of 2.51 mW cm−3 were observed for the 15 wt % 1‐TPU device. The capacitor charging experiments on the 15 wt % 1‐TPU composite device shows an excellent energy storage performance with the highest stored energies and measured charges of 198.8 μJ and 600 μC, respectively.
Tunable Electrochemical C−N versus N−N Bond Formation of Nitrogen‐Centered Radicals Enabled by Dehydrogenative Dearomatization: Biological Applications
Authors: Lv Shide , Han Xiaoxin , Wang Jian‐Yong , Zhou Mingyang , Wu Yanwei , Ma Li , Niu Liwei , Gao Wei , Zhou Jianhua , Hu Wei , Cui Yuezhi , Chen Jianbin
Published: March 2020

Herein, an environmentally friendly electrochemical approach is reported that takes advantage of the captodative effect and delocalization effect to generate nitrogen‐centered radicals (NCRs). By changing the reaction parameters of the electrode material and feedstock solubility, dearomatization enabled a selective dehydrogenative C−N versus N−N bond formation reaction. Hence, pyrido[1,2‐a]benzimidazole and tetraarylhydrazine frameworks were prepared through a sustainable transition‐metal‐ and exogenous oxidant‐free strategy with broad generality. Bioactivity assays demonstrated that pyrido[1,2‐a]benzimidazoles displayed antimicrobial activity and cytotoxicity against human cancer cells. Compound 21 exhibited good photochemical properties with a large Stokes shift (approximately 130 nm) and was successfully applied to subcellular imaging. A preliminary mechanism investigation and density functional theory (DFT) calculations revealed the possible reaction pathway.
Single‐Molecule Study of a Plasmon‐Induced Reaction for a Strongly Chemisorbed Molecule
Authors: Kazuma Emiko , Lee Minhui , Jung Jaehoon , Trenary Michael , Kim Yousoo
Published: March 2020

Chemical reactions induced by plasmons achieve effective solar‐to‐chemical energy conversion. However, the mechanism of these reactions, which generate a strong electric field, hot carriers, and heat through the excitation and decay processes, is still controversial. In addition, it is not fully understood which factor governs the mechanism. To obtain mechanistic knowledge, we investigated the plasmon‐induced dissociation of a single‐molecule strongly chemisorbed on a metal surface, two O2 species chemisorbed on Ag(110) with different orientations and electronic structures, using a scanning tunneling microscope (STM) combined with light irradiation at 5 K. A combination of quantitative analysis by the STM and density functional theory calculations revealed that the hot carriers are transferred to the antibonding (π*) orbitals of O2 strongly hybridized with the metal states and that the dominant pathway and reaction yield are determined by the electronic structures formed by the molecule–metal chemical interaction.
Gold‐Catalyzed 1,2‐Diarylation of Alkenes
Authors: Chintawar Chetan C. , Yadav Amit K. , Patil Nitin T.
Published: March 2020

Herein, we disclose the gold‐catalyzed 1,2‐diarylation of alkenes through the interplay of ligand‐enabled AuI/AuIII catalysis with the idiosyncratic π‐activation mode of gold complexes. Unlike the classical migratory‐insertion‐based approach to 1,2‐diarylation, the present approach not only circumvents the formation of direct Ar−Ar′ coupling and Heck‐type side products but more intriguingly demonstrates reactivity and selectivity complementary to those of previously known metal catalysis (Pd, Ni, or Cu). Detailed investigations to underpin the mechanistic scenario revealed oxidative addition of aryl iodides to an AuI complex to be the rate‐limiting step owing to the non‐innocent nature of the aryl alkene.
A Biomimetic Nanoparticle to “Lure and Kill” Phospholipase A2
Authors: Zhang Qiangzhe , Fang Ronnie H. , Gao Weiwei , Zhang Liangfang
Published: March 2020

Inhibition of phospholipase A2 (PLA2) has long been considered for treating various diseases associated with an elevated PLA2 activity. However, safe and effective PLA2 inhibitors remain unavailable. Herein, we report a biomimetic nanoparticle design that enables a “lure and kill” mechanism designed for PLA2 inhibition (denoted “L&K‐NP”). The L&K‐NPs are made of polymeric cores wrapped with modified red blood cell membrane with two inserted key components: melittin and oleyloxyethyl phosphorylcholine (OOPC). Melittin acts as a PLA2 attractant that works together with the membrane lipids to “lure” in‐coming PLA2 for attack. Meanwhile, OOPC acts as inhibitor that “kills” PLA2 upon enzymatic attack. Both compounds are integrated into the L&K‐NP structure, which voids toxicity associated with free molecules. In the study, L&K‐NPs effectively inhibit PLA2‐induced hemolysis. In mice administered with a lethal dose of venomous PLA2, L&K‐NPs also inhibit hemolysis and confer a significant survival benefit. Furthermore, L&K‐NPs show no obvious toxicity in mice. and the design provides a platform technology for a safe and effective anti‐PLA2 approach.
Enantioselective Synthesis of Atropisomers with Multiple Stereogenic Axes
Authors: Bao Xiaoze , Rodriguez Jean , Bonne Damien
Published: March 2020

Atropisomers possessing multiple stereogenic axes are intriguing molecules with huge potential. However, only few approaches for their enantioselective synthesis are available due to the difficulties in assembling various stereogenic axes with high enantiocontrol. Only recently, innovative methods have emerged, opening new possibilities for the synthesis of this original class of atropisomeric compounds. This Minireview describes the development of this field based on a classification of the multi‐axis systems according to the distance between the stereogenic axes and the strategy used to build them.
Carbon nanoparticles/polyvinyl alcohol composites with enhanced optical, thermal, mechanical, and flame‐retardant properties
Authors: Zahid Muhammad , Ali Salman , Saleem Sumaiya , Salman Muhammad , Khan Majid
Published: March 2020

In this work, polyvinyl alcohol (PVA) is chemically bonded to carbon nanoparticles (CNPs) by a very simple and versatile solution casting method. Five different kinds of CNPs/PVA composite films were prepared; 0.5, 1.0, 1.5, 2.0, and 3.0 wt% CNPs dispersed in PVA. The as‐prepared samples were characterized using various characterization techniques. The resulting nanocomposites proved to possess homogeneity and better mechanical, thermal, optical, and flame‐retardant properties than pure PVA. Most of the CNPs with average particle size ≤100 nm were homogeneously dispersed in the PVA matrix showing fluorescence in the violet color zone. The crystallinity of the nanocomposites show a decline in the diffraction intensity as compared to pure PVA which results from the dwelling of CNPs inside the gaps of stacked‐layer chains of PVA. The mechanical properties of nanocomposites indicated enhancement in toughness, elastic modulus and tensile strength with an increase in CNPs contents. The assessment for flame‐retardant properties was carried out through cone calorimetry. The results show a decrease in both total heat release rate (THRR) and peak heat release rate (pHRR) of the resulting nanocomposites as compared to pure PVA. The superior properties of the CNPs/PVA composites stemmed from the good interfacial bonding between the CNPs and PVA matrix.
Triple‐functional riboflavin‐based molecule for efficient atom transfer radical polymerization in miniemulsion media
Authors: Zaborniak Izabela , Surmacz Karolina , Flejszar Monika , Chmielarz Paweł
Published: March 2020

Triple‐functional riboflavin‐based macromolecule was synthesized providing an efficient activator regeneration by electron transfer atom transfer radical polymerization of butyl acrylate in a miniemulsion media in a fully oxygen tolerant environment. For the first time, the riboflavin‐inspired supramolecular structure fulfilled three primarily roles, acting simultaneously as (a) an initiator due to incorporation of bromine molecules in a ribitol tail by esterification reaction of riboflavin with α‐bromoisobutyryl bromide; (b) a reducing agent caused by the preservation of redox functionality of isoalloxazine ring in this structure; (c) and enables polymerization in air conditions. Electrochemical characterization of the riboflavin‐based molecule was conducted by a series of cyclic voltammetry measurements, determining an activation rate constant (ka = [1.34 ± 0.58] × 103 M−1 s−1) reflecting a reduction of the copper(II) catalytic complex in the presence of the multifunctional initiator. Proposed reaction system allowed to maintain control during polymerization proved by linear kinetics and a clear shift in molecular weights, resulting in the preparation of polymer brushes with narrow molecular weight distribution (Mw/Mn = 1.39) with high initiation efficiency (ƒi = 72%).
The predictability limit of the amplitude and phase of the Madden‐Julian oscillation
Authors: Lu Deyu , Ding Ruiqiang , Li Jianping
Published: March 2020

The Madden–Julian Oscillation (MJO) is characterized by slowly eastward‐propagating precipitation and circulation anomalies with time scales of about 30–80 days. Both the phase and amplitude of the MJO fluctuate with time as it propagates eastward. Despite recent progress in understanding the predictability limit of the MJO as a whole, little is known of the difference in the predictability limits of its amplitude and phase. This paper investigates these differences using the nonlinear local Lyapunov exponent approach, which provides an estimate of atmospheric predictability based on observational data. The predictability limit of the phase of the MJO is determined as ~32 days, which is higher than that of its amplitude (about 16 days). In state‐of‐the‐art operational forecast models, the phase of the MJO is also found to have a much better forecast skill than does its amplitude. The relatively low limit of the predictability of the amplitude will pose a challenge to MJO prediction.
The response of yeast vacuolar proteins: A novel rapid tool for Salmonella sp. screening
Authors: Nguyen Ngoc‐Tu , Lee Jaewoong , Woo Sung Min , Kim Yang‐Hoon , Min Jiho
Published: March 2020

Human health is recently affected by several factors in which food contamination is one of the most dangerous elements that damage directly on our bodies. In this study, we provided a novel approach for the rapid detection of Salmonella sp. at the molecular level using the response of Saccharomyces cerevisiae’s vacuoles. First, an augmentation of vacuoles intensity was observed by confocal microscopy after treating Salmonella strains with yeast cells. Second, the vacuolar enzymes were isolated and then analyzed by two‐dimensional electrophoresis for the screening of specific biomarkers. After that, various recombinant yeasts containing exclusive biomarkers were constructed by fusing these biomarkers with several fluorescent proteins. Finally, the recombinant strains showed the ability to detect Salmonella strains specifically by appropriate fluorescent signals from 20 CFU/mL after 15 Min of exposure.
Automatic variable selection for exposure‐driven propensity score matching with unmeasured confounders
Authors: Zöller Daniela , Wockner Leesa F. , Binder Harald
Published: March 2020

Multivariable model building for propensity score modeling approaches is challenging. A common propensity score approach is exposure‐driven propensity score matching, where the best model selection strategy is still unclear. In particular, the situation may require variable selection, while it is still unclear if variables included in the propensity score should be associated with the exposure and the outcome, with either the exposure or the outcome, with at least the exposure or with at least the outcome. Unmeasured confounders, complex correlation structures, and non‐normal covariate distributions further complicate matters. We consider the performance of different modeling strategies in a simulation design with a complex but realistic structure and effects on a binary outcome. We compare the strategies in terms of bias and variance in estimated marginal exposure effects. Considering the bias in estimated marginal exposure effects, the most reliable results for estimating the propensity score are obtained by selecting variables related to the exposure. On average this results in the least bias and does not greatly increase variances. Although our results cannot be generalized, this provides a counterexample to existing recommendations in the literature based on simple simulation settings. This highlights that recommendations obtained in simple simulation settings cannot always be generalized to more complex, but realistic settings and that more complex simulation studies are needed.
Developing and applying computational resources for biochemistry education
Authors: Craig Paul A.
Published: March 2020

Biochemistry is about structure and function, but it is also about data and this is where computers come in. From my time as a graduate student and post doc, whenever I encountered data I thought, “I can work this up by hand, but I think a computer could do a better job.” Since that time, I have been working at the interface of biochemistry and computers, by attracting talented students and collaborating with colleagues with complementary skills. This has resulted in several exciting projects: a simulation of 2D electrophoresis and tandem mass spectrometry, the human visualization project, and two different programs that enable biochemists to search protein structures for enzyme active sites: ProMOL (promol.org) and Moltimate (moltimate.appspot.com). The human side of software development for education involved finding the right students and colleagues, communicating effectively across disciplines, building and managing effective teams and the importance of serendipity throughout the process.