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Clinical implications of single- versus multiple-site keloid disorder: a retrospective study in an Asian population

Park TH, Park JH, Tirgan MH, Halim AS, Chang CH

Ann Plast Surg, 2015 Feb;74(2):248-51.
PMID: 24681623 DOI: 10.1097/SAP.0b013e3182a2b537

There is strong evidence of genetic susceptibility in individuals with keloid disorder. The purpose of this cross-sectional study was to determine the clinical relevance of our proposed variables on the multiplicity of keloids by further investigating the presence of other keloids and a family history.
Fulltext Validation of the Short Version (TLS-15) of the Triangular Love Scale (TLS-45) across 37 Languages

Kowal M, Sorokowski P, Dinić BM, Pisanski K, Gjoneska B, Frederick DA, et al.

Arch Sex Behav, 2024 Feb;53(2):839-857.
PMID: 37884798 DOI: 10.1007/s10508-023-02702-7

Love is a phenomenon that occurs across the world and affects many aspects of human life, including the choice of, and process of bonding with, a romantic partner. Thus, developing a reliable and valid measure of love experiences is crucial. One of the most popular tools to quantify love is Sternberg's 45-item Triangular Love Scale (TLS-45), which measures three love components: intimacy, passion, and commitment. However, our literature review reveals that most studies (64%) use a broad variety of shortened versions of the TLS-45. Here, aiming to achieve scientific consensus and improve the reliability, comparability, and generalizability of results across studies, we developed a short version of the scale-the TLS-15-comprised of 15 items with 5-point, rather than 9-point, response scales. In Study 1 (N = 7,332), we re-analyzed secondary data from a large-scale multinational study that validated the original TLS-45 to establish whether the scale could be truncated. In Study 2 (N = 307), we provided evidence for the three-factor structure of the TLS-15 and its reliability. Study 3 (N = 413) confirmed convergent validity and test-retest stability of the TLS-15. Study 4 (N = 60,311) presented a large-scale validation across 37 linguistic versions of the TLS-15 on a cross-cultural sample spanning every continent of the globe. The overall results provide support for the reliability, validity, and cross-cultural invariance of the TLS-15, which can be used as a measure of love components-either separately or jointly as a three-factor measure.
Fulltext Exploring Attitudes Toward "Sugar Relationships" Across 87 Countries: A Global Perspective on Exchanges of Resources for Sex and Companionship

Meskó N, Kowal M, Láng A, Kocsor F, Bandi SA, Putz A, et al.

Arch Sex Behav, 2024 Feb;53(2):811-837.
PMID: 38127113 DOI: 10.1007/s10508-023-02724-1

The current study investigates attitudes toward one form of sex for resources: the so-called sugar relationships, which often involve exchanges of resources for sex and/or companionship. The present study examined associations among attitudes toward sugar relationships and relevant variables (e.g., sex, sociosexuality, gender inequality, parasitic exposure) in 69,924 participants across 87 countries. Two self-report measures of Acceptance of Sugar Relationships (ASR) developed for younger companion providers (ASR-YWMS) and older resource providers (ASR-OMWS) were translated into 37 languages. We tested cross-sex and cross-linguistic construct equivalence, cross-cultural invariance in sex differences, and the importance of the hypothetical predictors of ASR. Both measures showed adequate psychometric properties in all languages (except the Persian version of ASR-YWMS). Results partially supported our hypotheses and were consistent with previous theoretical considerations and empirical evidence on human mating. For example, at the individual level, sociosexual orientation, traditional gender roles, and pathogen prevalence were significant predictors of both ASR-YWMS and ASR-OMWS. At the country level, gender inequality and parasite stress positively predicted the ASR-YWMS. However, being a woman negatively predicted the ASR-OMWS, but positively predicted the ASR-YWMS. At country-level, ingroup favoritism and parasite stress positively predicted the ASR-OMWS. Furthermore, significant cross-subregional differences were found in the openness to sugar relationships (both ASR-YWMS and ASR-OMWS scores) across subregions. Finally, significant differences were found between ASR-YWMS and ASR-OMWS when compared in each subregion. The ASR-YWMS was significantly higher than the ASR-OMWS in all subregions, except for Northern Africa and Western Asia.
Correction to: Validation of the Short Version (TLS-15) of the Triangular Love Scale (TLS-45) Across 37 Languages

Kowal M, Sorokowski P, Dinić BM, Pisanski K, Gjoneska B, Frederick DA, et al.

Arch Sex Behav, 2024 Feb;53(2):859-861.
PMID: 38038856 DOI: 10.1007/s10508-023-02751-y
Estrogenic chemicals and estrogenicity in river waters of South Korea and seven Asian countries

Duong CN, Ra JS, Cho J, Kim SD, Choi HK, Park JH, et al.

Chemosphere, 2010 Jan;78(3):286-93.
PMID: 19931116 DOI: 10.1016/j.chemosphere.2009.10.048

The effects of treatment processes on estrogenicity were evaluated by examining estradiol equivalent (EEQ) concentrations in influents and effluents of sewage treatment plants (STPs) located along Yeongsan and Seomjin rivers in Korea. The occurrence and distribution of estrogenic chemicals were also estimated for surface water in Korea and compared with seven other Asian countries including Laos, Cambodia, Vietnam, China, Indonesia, Thailand and Malaysia. Target compounds were nonylphenol (NP), octylphenol (OP), bisphenol A (BPA), estrone (E1), 17beta-estradiol (E2), 17alpha-ethynylestradiol (EE2) and genistein (Gen). Water samples were pretreated and analyzed by liquid-liquid extraction (LLE) and gas chromatography/mass spectrometry (GC/MS). The results showed that the treatment processes of Korean STPs were sufficient to reduce the estrogenic activity of municipal wastewater. The concentrations of phenolic xenoestrogens (i.e., NP, OP and BPA) in samples of Yeongsan and Seomjin rivers were smaller than those reported by previous studies in Korea. In most samples taken from the seven Asian countries, the presence of E2 and EE2 was a major contributor toward estrogenic activity. The EEQ concentrations in surface water samples of the seven Asian countries were at a higher level in comparison to that reported in European countries, America and Japan. However, further studies with more sampling frequencies and sampling areas should be carried out for better evaluation of the occurrence and distribution of estrogenic compounds in these Asian countries.
IAEA Activities on 67Cu, 186Re, 47Sc Theranostic Radionuclides and Radiopharmaceuticals

Jalilian AR, Gizawy MA, Alliot C, Takacs S, Chakarborty S, Rovais MRA, et al.

Curr Radiopharm, 2021;14(4):306-314.
PMID: 32988359 DOI: 10.2174/1874471013999200928162322

Despite interesting properties, the use of 67Cu, 186Re and 47Sc theranostic radionuclides in preclinical studies and clinical trials is curtailed by their limited availability due to a lack of widely established production methods. An IAEA Coordinated Research Project (CRP) was initiated to identify important technical issues related to the production and quality control of these emerging radionuclides and related radiopharmaceuticals, based on the request from IAEA Member States. The international team worked on targetry, separation, quality control and radiopharmaceutical aspects of the radionuclides obtained from research reactors and cyclotrons leading to preparation of a standard recommendations for all Member States. The CRP was initiated in 2016 with fourteen participants from thirteen Member States from four continents. Extraordinary results on the production, quality control and preclinical evaluation of selected radionuclides were reported in this project that was finalized in 2020. The outcomes, outputs and results of this project achieved by participating Member States are described in this minireview.
Robotic thyroidectomy learning curve for beginning surgeons with little or no experience of endoscopic surgery

Park JH, Lee J, Hakim NA, Kim HY, Kang SW, Jeong JJ, et al.

Head Neck, 2015 Dec;37(12):1705-11.
PMID: 24986508 DOI: 10.1002/hed.23824

This study assessed the results of robotic thyroidectomy by fellowship-trained surgeons in their initial independent practice, and whether standard fellowship training for robotic surgery shortens the learning curve.
Fulltext Oil Palm Phenolics Inhibit the In Vitro Aggregation of β-Amyloid Peptide into Oligomeric Complexes

Weinberg RP, Koledova VV, Shin H, Park JH, Tan YA, Sinskey AJ, et al.

Int J Alzheimers Dis, 2018;2018:7608038.
PMID: 29666700 DOI: 10.1155/2018/7608038

Alzheimer's disease is a severe neurodegenerative disease characterized by the aggregation of amyloid-β peptide (Aβ) into toxic oligomers which activate microglia and astrocytes causing acute neuroinflammation. Multiple studies show that the soluble oligomers of Aβ42 are neurotoxic and proinflammatory, whereas the monomers and insoluble fibrils are relatively nontoxic. We show that Aβ42 aggregation is inhibited in vitro by oil palm phenolics (OPP), an aqueous extract from the oil palm tree (Elaeis guineensis). The data shows that OPP inhibits stacking of β-pleated sheets, which is essential for oligomerization. We demonstrate the inhibition of Aβ42 aggregation by (1) mass spectrometry; (2) Congo Red dye binding; (3) 2D-IR spectroscopy; (4) dynamic light scattering; (5) transmission electron microscopy; and (6) transgenic yeast rescue assay. In the yeast rescue assay, OPP significantly reduces the cytotoxicity of aggregating neuropeptides in yeast genetically engineered to overexpress these peptides. The data shows that OPP inhibits (1) the aggregation of Aβ into oligomers; (2) stacking of β-pleated sheets; and (3) fibrillar growth and coalescence. These inhibitory effects prevent the formation of neurotoxic oligomers and hold potential as a means to reduce neuroinflammation and neuronal death and thereby may play some role in the prevention or treatment of Alzheimer's disease.
Clozapine Use for Bipolar Disorder: An Asian Psychotropic Prescription Patterns Consortium Study

Loo LWJ, Chew QH, Lin SK, Yang SY, Ouyang WC, Chen CK, et al.

J Clin Psychopharmacol, 2023 Apr 18.
PMID: 37068038 DOI: 10.1097/JCP.0000000000001693

BACKGROUND: Pharmacoepidemiological studies of clozapine use to treat bipolar disorder (BD), especially in Asia, are rare, although they can provide insights into associated clinical characteristics and support international comparisons of indications and drug dosing.
METHODS: We examined the prevalence and clinical correlates of clozapine treatment for BD in 13 Asian countries and regions (China, Hong Kong SAR, India, Indonesia, Japan, Korea, Malaysia, Myanmar, Pakistan, Singapore, Sri Lanka, Taiwan, and Thailand) within an Asian Prescription Patterns Research Consortium. We compared BD patients treated with clozapine or not in initial bivariate comparisons followed by multivariable logistic regression modeling.
RESULTS: Clozapine was given to 2.13% of BD patients overall, at a mean daily dose of 275 (confidence interval, 267-282) chlorpromazine-equivalent mg/day. Patients receiving clozapine were older, more likely males, hospitalized, currently manic, and given greater numbers of mood-stabilizing and antipsychotic drugs in addition to clozapine. Logistic regression revealed that older age, male sex, current mania, and greater number of other antipsychotics remained significantly associated with clozapine treatment. Clozapine use was not associated with depressed mood, remission of illness, suicidal risk, or electroconvulsive treatment within the previous 12 months.
CONCLUSIONS: The identified associations of clozapine use with particular clinical features call for vigilance in personalized clinical monitoring so as to optimize clinical outcomes of BD patients and to limit risks of adverse effects of polytherapy.
Pharmacoepidemiology and Clinical Correlates of Lithium Treatment for Bipolar Disorder in Asia

Shuy YK, Santharan S, Chew QH, Lin SK, Ouyang WC, Chen CK, et al.

J Clin Psychopharmacol, 2024 01 16;44(2):117-123.
PMID: 38230861 DOI: 10.1097/JCP.0000000000001813

BACKGROUND: As clinical practices with lithium salts for patients diagnosed with bipolar disorder (BD) are poorly documented in Asia, we studied the prevalence and clinical correlates of lithium use there to support international comparisons.
METHODS: We conducted a cross-sectional study of use and dosing of lithium salts for BD patients across 13 Asian sites and evaluated bivariate relationships of lithium treatment with clinical correlates followed by multivariate logistic regression modeling.
RESULTS: In a total of 2139 BD participants (52.3% women) of mean age 42.4 years, lithium salts were prescribed in 27.3% of cases overall, varying among regions from 3.20% to 59.5%. Associated with lithium treatment were male sex, presence of euthymia or mild depression, and a history of seasonal mood change. Other mood stabilizers usually were given with lithium, often at relatively high doses. Lithium use was associated with newly emerging and dose-dependent risk of tremors as well as risk of hypothyroidism. We found no significant differences in rates of clinical remission or of suicidal behavior if treatment included lithium or not.
CONCLUSIONS: Study findings clarify current prevalence, dosing, and clinical correlates of lithium treatment for BD in Asia. This information should support clinical decision-making regarding treatment of BD patients and international comparisons of therapeutic practices.
Fulltext 2019 Seoul Consensus on Esophageal Achalasia Guidelines

Jung HK, Hong SJ, Lee OY, Pandolfino J, Park H, Miwa H, et al.

J Neurogastroenterol Motil, 2020 04 30;26(2):180-203.
PMID: 32235027 DOI: 10.5056/jnm20014

Esophageal achalasia is a primary motility disorder characterized by insufficient lower esophageal sphincter relaxation and loss of esophageal peristalsis. Achalasia is a chronic disease that causes progressive irreversible loss of esophageal motor function. The recent development of high-resolution manometry has facilitated the diagnosis of achalasia, and determining the achalasia subtypes based on high-resolution manometry can be important when deciding on treatment methods. Peroral endoscopic myotomy is less invasive than surgery with comparable efficacy. The present guidelines (the "2019 Seoul Consensus on Esophageal Achalasia Guidelines") were developed based on evidence-based medicine; the Asian Neurogastroenterology and Motility Association and Korean Society of Neurogastroenterology and Motility served as the operating and development committees, respectively. The development of the guidelines began in June 2018, and a draft consensus based on the Delphi process was achieved in April 2019. The guidelines consist of 18 recommendations: 2 pertaining to the definition and epidemiology of achalasia, 6 pertaining to diagnoses, and 10 pertaining to treatments. The endoscopic treatment section is based on the latest evidence from meta-analyses. Clinicians (including gastroenterologists, upper gastrointestinal tract surgeons, general physicians, nurses, and other hospital workers) and patients could use these guidelines to make an informed decision on the management of achalasia.
Fulltext The Practice of Gastrointestinal Motility Laboratory During COVID-19 Pandemic: Position Statements of the Asian Neurogastroenterology and Motility Association (ANMA-GML-COVID-19 Position Statements)

Siah KTH, Rahman MM, Ong AML, Soh AYS, Lee YY, Xiao Y, et al.

J Neurogastroenterol Motil, 2020 07 30;26(3):299-310.
PMID: 32606253 DOI: 10.5056/jnm20107

During the Coronavirus Disease 2019 (COVID-19) pandemic, practices of gastrointestinal procedures within the digestive tract require special precautions due to the risk of contraction of severe acute respiratoy syndrome coronavirus-2 (SARS-CoV-2) infection. Many procedures in the gastrointestinal motility laboratory may be considered moderate to high-risk for viral transmission. Healthcare staff working in gastrointestinal motility laboratories are frequently exposed to splashes, air droplets, mucus, or saliva during the procedures. Moreover, some are aerosol-generating and thus have a high risk of viral transmission. There are multiple guidelines on the practices of gastrointestinal endoscopy during this pandemic. However, such guidelines are still lacking and urgently needed for the practice of gastrointestinal motility laboratories. Hence, the Asian Neurogastroenterology and Motility Association had organized a group of gastrointestinal motility experts and infectious disease specialists to produce a position statement paper based-on current available evidence and consensus opinion with aims to provide a clear guidance on the practices of gastrointestinal motility laboratories during the COVID-19 pandemic. This guideline covers a wide range of topics on gastrointestinal motility activities from scheduling a motility test, the precautions at different steps of the procedure to disinfection for the safety and well-being of the patients and the healthcare workers. These practices may vary in different countries depending on the stages of the pandemic, local or institutional policy, and the availability of healthcare resources. This guideline is useful when the transmission rate of SARS-CoV-2 is high. It may change rapidly depending on the situation of the epidemic and when new evidence becomes available.
Prediction of Mortality Among Patients With Isolated Traumatic Brain Injury Using Machine Learning Models in Asian Countries: An International Multi-Center Cohort Study

Song J, Shin SD, Jamaluddin SF, Chiang WC, Tanaka H, Song KJ, et al.

J Neurotrauma, 2023 Jul;40(13-14):1376-1387.
PMID: 36656672 DOI: 10.1089/neu.2022.0280

Abstract Traumatic brain injury (TBI) is a significant healthcare concern in several countries, accounting for a major burden of morbidity, mortality, disability, and socioeconomic losses. Although conventional prognostic models for patients with TBI have been validated, their performance has been limited. Therefore, we aimed to construct machine learning (ML) models to predict the clinical outcomes in adult patients with isolated TBI in Asian countries. The Pan-Asian Trauma Outcome Study registry was used in this study, and the data were prospectively collected from January 1, 2015, to December 31, 2020. Among a total of 6540 patients (≥ 15 years) with isolated moderate and severe TBI, 3276 (50.1%) patients were randomly included with stratification by outcomes and subgrouping variables for model evaluation, and 3264 (49.9%) patients were included for model training and validation. Logistic regression was considered as a baseline, and ML models were constructed and evaluated using the area under the precision-recall curve (AUPRC) as the primary outcome metric, area under the receiver operating characteristic curve (AUROC), and precision at fixed levels of recall. The contribution of the variables to the model prediction was measured using the SHapley Additive exPlanations (SHAP) method. The ML models outperformed logistic regression in predicting the in-hospital mortality. Among the tested models, the gradient-boosted decision tree showed the best performance (AUPRC, 0.746 [0.700-0.789]; AUROC, 0.940 [0.929-0.952]). The most powerful contributors to model prediction were the Glasgow Coma Scale, O2 saturation, transfusion, systolic and diastolic blood pressure, body temperature, and age. Our study suggests that ML techniques might perform better than conventional multi-variate models in predicting the outcomes among adult patients with isolated moderate and severe TBI.
Fulltext 2017 Multimodality Appropriate Use Criteria for Noninvasive Cardiac Imaging: Expert Consensus of the Asian Society of Cardiovascular Imaging

ASCI Practice Guideline Working Group, Beck KS, Kim JA, Choe YH, Sim KH, Hoe J, et al.

Korean J Radiol, 2017 Nov-Dec;18(6):871-880.
PMID: 29089819 DOI: 10.3348/kjr.2017.18.6.871

In 2010, the Asian Society of Cardiovascular Imaging (ASCI) provided recommendations for cardiac CT and MRI, and this document reflects an update of the 2010 ASCI appropriate use criteria (AUC). In 2016, the ASCI formed a new working group for revision of AUC for noninvasive cardiac imaging. A major change that we made in this document is the rating of various noninvasive tests (exercise electrocardiogram, echocardiography, positron emission tomography, single-photon emission computed tomography, radionuclide imaging, cardiac magnetic resonance, and cardiac computed tomography/angiography), compared side by side for their applications in various clinical scenarios. Ninety-five clinical scenarios were developed from eight selected pre-existing guidelines and classified into four sections as follows: 1) detection of coronary artery disease, symptomatic or asymptomatic; 2) cardiac evaluation in various clinical scenarios; 3) use of imaging modality according to prior testing; and 4) evaluation of cardiac structure and function. The clinical scenarios were scored by a separate rating committee on a scale of 1-9 to designate appropriate use, uncertain use, or inappropriate use according to a modified Delphi method. Overall, the AUC ratings for CT were higher than those of previous guidelines. These new AUC provide guidance for clinicians choosing among available testing modalities for various cardiac diseases and are also unique, given that most previous AUC for noninvasive imaging include only one imaging technique. As cardiac imaging is multimodal in nature, we believe that these AUC will be more useful for clinical decision making.
Fulltext Global, regional, and national levels and causes of maternal mortality during 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013

Kassebaum NJ, Bertozzi-Villa A, Coggeshall MS, Shackelford KA, Steiner C, Heuton KR, et al.

Lancet, 2014 Sep 13;384(9947):980-1004.
PMID: 24797575 DOI: 10.1016/S0140-6736(14)60696-6

BACKGROUND: The fifth Millennium Development Goal (MDG 5) established the goal of a 75% reduction in the maternal mortality ratio (MMR; number of maternal deaths per 100,000 livebirths) between 1990 and 2015. We aimed to measure levels and track trends in maternal mortality, the key causes contributing to maternal death, and timing of maternal death with respect to delivery.
METHODS: We used robust statistical methods including the Cause of Death Ensemble model (CODEm) to analyse a database of data for 7065 site-years and estimate the number of maternal deaths from all causes in 188 countries between 1990 and 2013. We estimated the number of pregnancy-related deaths caused by HIV on the basis of a systematic review of the relative risk of dying during pregnancy for HIV-positive women compared with HIV-negative women. We also estimated the fraction of these deaths aggravated by pregnancy on the basis of a systematic review. To estimate the numbers of maternal deaths due to nine different causes, we identified 61 sources from a systematic review and 943 site-years of vital registration data. We also did a systematic review of reports about the timing of maternal death, identifying 142 sources to use in our analysis. We developed estimates for each country for 1990-2013 using Bayesian meta-regression. We estimated 95% uncertainty intervals (UIs) for all values.
FINDINGS: 292,982 (95% UI 261,017-327,792) maternal deaths occurred in 2013, compared with 376,034 (343,483-407,574) in 1990. The global annual rate of change in the MMR was -0·3% (-1·1 to 0·6) from 1990 to 2003, and -2·7% (-3·9 to -1·5) from 2003 to 2013, with evidence of continued acceleration. MMRs reduced consistently in south, east, and southeast Asia between 1990 and 2013, but maternal deaths increased in much of sub-Saharan Africa during the 1990s. 2070 (1290-2866) maternal deaths were related to HIV in 2013, 0·4% (0·2-0·6) of the global total. MMR was highest in the oldest age groups in both 1990 and 2013. In 2013, most deaths occurred intrapartum or postpartum. Causes varied by region and between 1990 and 2013. We recorded substantial variation in the MMR by country in 2013, from 956·8 (685·1-1262·8) in South Sudan to 2·4 (1·6-3·6) in Iceland.
INTERPRETATION: Global rates of change suggest that only 16 countries will achieve the MDG 5 target by 2015. Accelerated reductions since the Millennium Declaration in 2000 coincide with increased development assistance for maternal, newborn, and child health. Setting of targets and associated interventions for after 2015 will need careful consideration of regions that are making slow progress, such as west and central Africa.
FUNDING: Bill & Melinda Gates Foundation.
Fulltext In vitro invasion inhibition assay using antibodies against Plasmodium knowlesi Duffy binding protein alpha and apical membrane antigen protein 1 in human erythrocyte-adapted P. knowlesi A1-H.1 strain

Muh F, Lee SK, Hoque MR, Han JH, Park JH, Firdaus ER, et al.

Malar J, 2018 Jul 27;17(1):272.
PMID: 30049277 DOI: 10.1186/s12936-018-2420-4

BACKGROUND: The rapid process of malaria erythrocyte invasion involves ligand-receptor interactions. Inducing antibodies against specific ligands or receptors that abrogate the invasion process is a key challenge for blood stage vaccine development. However, few candidates were reported and remain to be validated for the discovery of new vaccine candidates in Plasmodium knowlesi.
METHODS: In order to investigate the efficacy of pre-clinical vaccine candidates in P. knowlesi-infected human cases, this study describes an in vitro invasion inhibition assay, using a P. knowlesi strain adapted to in vitro growth in human erythrocytes, PkA1-H.1. Recombinant proteins of P. knowlesi Duffy binding protein alpha (PkDBPα) and apical membrane antigen 1 (PkAMA1) were produced in Escherichia coli system and rabbit antibodies were generated from immune animals.
RESULTS: PkDBPα and PkAMA1 recombinant proteins were expressed as insoluble and produced as a functional refolded form for this study. Antibodies against PkDBPα and PkAMA1 specifically recognized recombinant proteins and native parasite proteins in schizont-stage parasites on the merozoite organelles. Single and combination of anti-PkDBPα and anti-PkAMA1 antibodies elicited strong growth inhibitory effects on the parasite in concentration-dependent manner. Meanwhile, IgG prevalence of PkDBPα and PkAMA1 were observed in 13.0 and 46.7% in human clinical patients, respectively.
CONCLUSION: These data provide support for the validation of in vitro growth inhibition assay using antibodies of DBPα and AMA1 in human-adapted P. knowlesi parasite PkA1-H.1 strain.
Fulltext Protection of Reinforced Concrete Structures of Waste Water Treatment Reservoirs with Stainless Steel Coating Using Arc Thermal Spraying Technique in Acidified Water

Lee HS, Park JH, Singh JK, Ismail MA

Materials (Basel), 2016 Sep 03;9(9).
PMID: 28773875 DOI: 10.3390/ma9090753

Waste water treatment reservoirs are contaminated with many hazardous chemicals and acids. Reservoirs typically comprise concrete and reinforcement steel bars, and the main elements responsible for their deterioration are hazardous chemicals, acids, and ozone. Currently, a variety of techniques are being used to protect reservoirs from exposure to these elements. The most widely used techniques are stainless steel plating and polymeric coating. In this study, a technique known as arc thermal spraying was used. It is a more convenient and economical method for protecting both concrete and reinforcement steel bar from deterioration in waste water treatment reservoirs. In this study, 316L stainless steel coating was applied to a concrete surface, and different electrochemical experiments were performed to evaluate the performance of coatings in different acidic pH solutions. The coating generated from the arc thermal spraying process significantly protected the concrete surface from corrosion in acidic pH solutions, owing to the formation of a double layer capacitance-a mixture of Cr3+ enriched with Cr₂O₃ and Cr-hydroxide in inner and Fe3+ oxide on the outer layer of the coating. The formation of this passive film is defective owing to the non-homogeneous 316L stainless steel coating surface. In the pH 5 solution, the growth of a passive film is adequate due to the presence of un-dissociated water molecules in the aqueous sulfuric acid solution. The coated surface is sealed with alkyl epoxide, which acts as a barrier against the penetration of acidic solutions. This coating exhibits higher impedance values among the three studied acidic pH solutions.
Fulltext Crystallization of Electrodeposited Germanium Thin Film on Silicon (100)

Abidin MSZ, Matsumura R, Anisuzzaman M, Park JH, Muta S, Mahmood MR, et al.

Materials (Basel), 2013 Nov 06;6(11):5047-5057.
PMID: 28788375 DOI: 10.3390/ma6115047

We report the crystallization of electrodeposited germanium (Ge) thin films on n-silicon (Si) (100) by rapid melting process. The electrodeposition was carried out in germanium (IV) chloride: propylene glycol (GeCl₄:C₃H₈O₂) electrolyte with constant current of 50 mA for 30 min. The measured Raman spectra and electron backscattering diffraction (EBSD) images show that the as-deposited Ge thin film was amorphous. The crystallization of deposited Ge was achieved by rapid thermal annealing (RTA) at 980 °C for 1 s. The EBSD images confirm that the orientations of the annealed Ge are similar to that of the Si substrate. The highly intense peak of Raman spectra at 300 cm(-1) corresponding to Ge-Ge vibration mode was observed, indicating good crystal quality of Ge. An additional sub peak near to 390 cm(-1) corresponding to the Si-Ge vibration mode was also observed, indicating the Ge-Si mixing at Ge/Si interface. Auger electron spectroscopy (AES) reveals that the intermixing depth was around 60 nm. The calculated Si fraction from Raman spectra was found to be in good agreement with the value estimated from Ge-Si equilibrium phase diagram. The proposed technique is expected to be an effective way to crystallize Ge films for various device applications as well as to create strain at the Ge-Si interface for enhancement of mobility.
Fulltext The Effects of Annealing Temperatures on Composition and Strain in Si x Ge1-x Obtained by Melting Growth of Electrodeposited Ge on Si (100)

Abidin MSZ, Morshed T, Chikita H, Kinoshita Y, Muta S, Anisuzzaman M, et al.

Materials (Basel), 2014 Feb 24;7(2):1409-1421.
PMID: 28788521 DOI: 10.3390/ma7021409

The effects of annealing temperatures on composition and strain in Si
x
Ge1-x, obtained by rapid melting growth of electrodeposited Ge on Si (100) substrate were investigated. Here, a rapid melting process was performed at temperatures of 1000, 1050 and 1100 °C for 1 s. All annealed samples show single crystalline structure in (100) orientation. A significant appearance of Si-Ge vibration mode peak at ~400 cm-1 confirms the existence of Si-Ge intermixing due to out-diffusion of Si into Ge region. On a rapid melting process, Ge melts and reaches the thermal equilibrium in short time. Si at Ge/Si interface begins to dissolve once in contact with the molten Ge to produce Si-Ge intermixing. The Si fraction in Si-Ge intermixing was calculated by taking into account the intensity ratio of Ge-Ge and Si-Ge vibration mode peaks and was found to increase with the annealing temperatures. It is found that the strain turns from tensile to compressive as the annealing temperature increases. The Si fraction dependent thermal expansion coefficient of Si
x
Ge1-x is a possible cause to generate such strain behavior. The understanding of compositional and strain characteristics is important in Ge/Si heterostructure as these properties seem to give significant effects in device performance.
Fulltext Cross-species reactivity of antibodies against Plasmodium vivax blood-stage antigens to Plasmodium knowlesi

Muh F, Kim N, Nyunt MH, Firdaus ER, Han JH, Hoque MR, et al.

PLoS Negl Trop Dis, 2020 06;14(6):e0008323.
PMID: 32559186 DOI: 10.1371/journal.pntd.0008323

Malaria is caused by multiple different species of protozoan parasites, and interventions in the pre-elimination phase can lead to drastic changes in the proportion of each species causing malaria. In endemic areas, cross-reactivity may play an important role in the protection and blocking transmission. Thus, successful control of one species could lead to an increase in other parasite species. A few studies have reported cross-reactivity producing cross-immunity, but the extent of cross-reactive, particularly between closely related species, is poorly understood. P. vivax and P. knowlesi are particularly closely related species causing malaria infections in SE Asia, and whilst P. vivax cases are in decline, zoonotic P. knowlesi infections are rising in some areas. In this study, the cross-species reactivity and growth inhibition activity of P. vivax blood-stage antigen-specific antibodies against P. knowlesi parasites were investigated. Bioinformatics analysis, immunofluorescence assay, western blotting, protein microarray, and growth inhibition assay were performed to investigate the cross-reactivity. P. vivax blood-stage antigen-specific antibodies recognized the molecules located on the surface or released from apical organelles of P. knowlesi merozoites. Recombinant P. vivax and P. knowlesi proteins were also recognized by P. knowlesi- and P. vivax-infected patient antibodies, respectively. Immunoglobulin G against P. vivax antigens from both immune animals and human malaria patients inhibited the erythrocyte invasion by P. knowlesi. This study demonstrates that there is extensive cross-reactivity between antibodies against P. vivax to P. knowlesi in the blood stage, and these antibodies can potently inhibit in vitro invasion, highlighting the potential cross-protective immunity in endemic areas.

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