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Fulltext Ionic conductivity studies on magnesium-based cellulose acetate polymer gel electrolytes

Aniza Omar, Ainnur Sherene Kamisan, Muhd Zu Azhan bin Yahya, Siti Zafirah Zainal Abidin, Ab Malik Marwan Ali, Siti Irma Yuana Saaid

Scientific Research Journal, 2015;12(2):0-0.
MyJurnal

Magnesium-based polymer gel electrolytes consist of magnesium triflate (MgTf) salt, a mixture of ethylene carbonate (EC) and diethyl carbonate (DEC) solvents as well as cellulose acetate as a polymeric agent were prepared via direct dissolution method. The highest ionic conductivity obtained for MgTf-EC:DEC(1:1) liquid electrolytes was 2.66 x 10-3 S cm-1 and enhanced to 2.73 x 10-3 S cm-1 with the addition of cellulose acetate. These results were in agreement with the activation energy obtained with the lowest value of 0.11. The best explanation on the enhancement in ionic conductivity of PGE is due to the “breathing polymeric chain model”. The plots of conductivity-temperature shown to obey an Arrhenius rule. The electrical properties of the sample with the highest conductivity were analyzed using electrical permittivity-based frequency and temperature dependence in the range of 100 Hz - 1 MHz and 303-373K, respectively. The variation in dielectric permittivity (εr and εi) as a function of frequency at different temperatures exhibited decays at higher frequencies and a dispersive behavior at low frequencies. Based on the observed electrical properties, it can be inferred that this polymer gel electrolyte could be a promising candidate as an electrolyte in electrochemical devices.
Fulltext Comparison of energy and performance from biodegradation of freeze dried and spray dried Algae biomass

Muhamad Haikal Zainal, Khairul Baqir Alkhair Khairul Amin, Oskar Hasdinor Hassan, Sharifah Aminah Syed Mohamad, Abd Malik Marwan Ali, Fathiah Abdullah, et al.

Pertanika Journal of Science & Technology, 2017;25(103):53-62.
MyJurnal

Many kinds of substrates have been used to investigate bioelectricity production with Microbial Fuel Cell (MFC). Dry algae biomass has the highest maximum power density compared to other substrates due to high carbon sources from its lipid. However, the bacterial digestion of algae biomass is not simple because of the complexity and strength of the algal cell wall structure. An algae biomass extraction is needed to break the cell wall structure and facilitate digestion. Spray drying method is commonly used in highvalue products but may degrade some algal components which are crucial for microbial degradation in MFC, while the freeze-drying method is able to preserve algal cell constituents. The MFC was fed with freeze dried and spray dried algae biomass to produce energy and determine the degradation efficiency. Results showed the average voltage generated was 739 mV and 740 mV from freeze dried and spray dried algae biomass, respectively. The maximum power density of freeze dried algae biomass is 159.9 mW/m2 and spray dried algae biomass is 152.3 mW/m2. Freeze dried algae biomass has 54.2% of COD removal and 28.4% of Coulombic Efficiency while spray dried algae biomass has 50.1% of COD removal and 24.9% of Coulombic Efficiency.
Fulltext Electrical properties of plasticised Proton conducting MG49 polymer electrolyte

Zaidatul Salwa Mahmud, Siti Nor Hafiza Mohd Yusoff, Nur Hamizah Mohd Zaki, Mohamad Fariz Mohamad Taib, Mohamad Kamil Yaakob, Oskar Hasdinor Hassan, et al.

Pertanika Journal of Science & Technology, 2017;25(103):363-370.
MyJurnal

A free-standing film consisting of 49% PMMA grafted-natural rubber electrolytes was prepared. Potassium hydroxide (KOH) and propylene carbonate (PC) was added to the preparation and the properties of the electrolytes measured using complex impedance analysis at various temperatures. The addition of plasticiser in alkaline polymer electrolyte gives rise to the ionic conductivity up to 2.647 x 10-6 S cm-1 at composition consisting of 50wt.% of PC. The dielectric properties of the GPEs were studied and the relaxations at higher frequencies appear in both imaginary and real part of the permittivity. These relaxations are related with the interface ion polarisations at the polymer-electrode interface and segmental motion of the polymer electrolyte molecular chains. The influence of the impedance spectra on temperature was studied. Results showed rising temperature increased conductivity, top frequency (f*), relative dielectric constant (εr) and geometrical capacitance (Cg) due to the mobility of free ion carriers.
Case series of buprenorphine injectors in Kuala Lumpur, Malaysia

Bruce RD, Govindasamy S, Sylla L, Haddad MS, Kamarulzaman A, Altice FL

Am J Drug Alcohol Abuse, 2008;34(4):511-7.
PMID: 18584580 DOI: 10.1080/00952990802122259

Diversion of buprenorphine has been described in settings where it is legally prescribed and has become an increasing concern in Malaysia; it resulted in banning of buprenorphine in Singapore where unsubstantiated case reports suggested that buprenorphine injection was associated with particularly poor outcomes. We therefore conducted a case series of qualitative interviews with buprenorphine injectors in Kuala Lumpur, Malaysia to examine further the issues surrounding buprenorphine injection as well as the abuse of midazolam in combination with buprenorphine. Interviews with 19 men do not suggest significant adverse health consequences from buprenorphine injection alone and injectors have adapted diverted buprenorphine as a treatment modality. A subset of these injectors, however, combined buprenorphine and midazolam for euphoric effects with resultant symptoms of a possible pharmacological interaction. Prospective cohort studies, rather than hospital-derived samples, are needed to better understand the safety of buprenorphine injection.
The Impact of Alcohol Use and Related Disorders on the HIV Continuum of Care: a Systematic Review : Alcohol and the HIV Continuum of Care

Vagenas P, Azar MM, Copenhaver MM, Springer SA, Molina PE, Altice FL

Curr HIV/AIDS Rep, 2015 Dec;12(4):421-36.
PMID: 26412084 DOI: 10.1007/s11904-015-0285-5

Alcohol use is highly prevalent globally with numerous negative consequences to human health, including HIV progression, in people living with HIV (PLH). The HIV continuum of care, or treatment cascade, represents a sequence of targets for intervention that can result in viral suppression, which ultimately benefits individuals and society. The extent to which alcohol impacts each step in the cascade, however, has not been systematically examined. International targets for HIV treatment as prevention aim for 90 % of PLH to be diagnosed, 90 % of them to be prescribed with antiretroviral therapy (ART), and 90 % to achieve viral suppression; currently, only 20 % of PLH are virally suppressed. This systematic review, from 2010 through May 2015, found 53 clinical research papers examining the impact of alcohol use on each step of the HIV treatment cascade. These studies were mostly cross-sectional or cohort studies and from all income settings. Most (77 %) found a negative association between alcohol consumption on one or more stages of the treatment cascade. Lack of consistency in measurement, however, reduced the ability to draw consistent conclusions. Nonetheless, the strong negative correlations suggest that problematic alcohol consumption should be targeted, preferably using evidence-based behavioral and pharmacological interventions, to indirectly increase the proportion of PLH achieving viral suppression, to achieve treatment as prevention mandates, and to reduce HIV transmission.
Fulltext The loading effect of Pt clusters on Pt/graphene nano sheets catalysts

Siburian R, Ali AMM, Sebayang K, Supeno M, Tarigan K, Simanjuntak C, et al.

Sci Rep, 2021 Jan 28;11(1):2532.
PMID: 33510232 DOI: 10.1038/s41598-020-80472-1

In this paper, we report about chemically interaction between Pt Subnano-Clusters on Graphene Nano Sheets (GNS). The aim of this research is to clarify the size effect of Pt clusters on Pt 1-7 wt.%/GNS. This research is an experimental laboratory research. GNS was synthesized by using modified Hummer's method and 1-7 wt.% Pt/GNS were prepared with impregnation method. Then, they were analyzed with TG/DTA, XRD, TEM and XPS, respectively. The results show that Pt clusters are well deposited on GNS (TG/DTA and TEM data). Those data also are consistent with XRD data. The weak and broad peaks appear at 2θ = 39°, indicating Pt metal exists on GNS. The state of Pt is confirmed by using XPS. The appearance of Pt 4f. peaks proves that Pt metal is chemical interaction on GNS. The size of Pt clusters may affect the chemically properties of Pt/GNS catalysts.
Mucoadhesive Low Molecular Chitosan Complexes to Protect rHuKGF from Proteolysis: In-vitro Characterization and FHs 74 Int Cell Proliferation Studies

Tee YN, Kumar PV, Maki MAA, Elumalai M, Rahman SAKMEH, Cheah SC

Curr Pharm Biotechnol, 2021;22(7):969-982.
PMID: 33342408 DOI: 10.2174/1389201021666201218124450

BACKGROUND: Recombinant Keratinocyte Growth Factor (rHuKGF) is a therapeutic protein used widely in oral mucositis after chemotherapy in various cancers, stimulating lung morphogenesis and gastrointestinal tract cell proliferation. In this research study, chitosan-rHuKGF polymeric complex was implemented to improve the stability of rHuKGF and used as rejuvenation therapy for the treatment of oral mucositis in cancer patients.
OBJECTIVE: Complexation of rHuKGF with mucoadhesive low molecular weight chitosan to protect rHuKGF from proteolysis and investigate the effect of chitosan-rHuKGF complex on the proliferation rate of FHs 74 Int cells.
METHODS: The interaction between chitosan and rHuKGF was studied by molecular docking. Malvern ZetaSizer Nano Zs and Fourier-Transform Infrared spectroscopy (FTIR) tests were carried out to characterize the chitosan-rHuKGF complex. In addition, SDS-PAGE was performed to investigate the interaction between chitosan-rHuKGF complex and pepsin. The effect of chitosan-rHuKGF complex on the proliferation rate of FHs 74 Int cells was studied by MTT assay.
RESULTS: Chitosan-rHuKGF complex was formed through the hydrogen bonding proven by the docking studies. A stable chitosan-rHuKGF complex was formed at pH 4.5 and was protected from proteolysis and assessed by SDS PAGE. According to the MTT assay results, chitosan-rHuKGF complex increased the cell proliferation rate of FHs 74 Int cells.
CONCLUSION: The developed complex improved the stability and the biological function of rHuKGF.
Concomitant measurements of serum annexin A5 levels and hematological indices as markers in recent and old myocardial infarction with low ejection fraction: A preliminary study

Alhusseiny AH, Al-Nimer MS, Mohammad FI, Ali Jadoo SA

Int J Cardiol, 2016 Nov 15;223:514-518.
PMID: 27552568 DOI: 10.1016/j.ijcard.2016.08.244

Serum annexin A5 (anxA5) level is significantly increased in patients with acute coronary syndrome. Hematological indices are significantly increased in patients with ischemic heart disease. This study aimed to demonstrate the changes in the distribution of blood cells and the levels of anxA5 in patients presented with significant low ejection fraction ST-elevation acute myocardial infarction (STEMI) in comparison with corresponding patients with ischemic heart disease.
Extended-release naltrexone reduces alcohol consumption among released prisoners with HIV disease as they transition to the community

Springer SA, Di Paola A, Azar MM, Barbour R, Krishnan A, Altice FL

Drug Alcohol Depend, 2017 05 01;174:158-170.
PMID: 28334661 DOI: 10.1016/j.drugalcdep.2017.01.026

BACKGROUND: Alcohol use disorders (AUDs) are highly prevalent among persons living with HIV (PLH) within the criminal justice system (CJS). Extended-release naltrexone (XR-NTX) has not been previously evaluated among CJS-involved PLH with AUDs.
METHODS: A randomized, double-blind, placebo-controlled trial was conducted among 100 HIV+ prisoners with AUDs. Participants were randomized 2:1 to receive 6 monthly injections of XR-NTX or placebo starting one week prior to release. Using multiple imputation strategies for data missing completely at random, data were analyzed for the 6-month post-incarceration period. Main outcomes included: time to first heavy drinking day; number of standardized drinks/drinking day; percent of heavy drinking days; pre- to post-incarceration change in average drinks/day; total number of drinking days; and a composite alcohol improvement score comprised of all 5 parameters.
RESULTS: There was no statistically significant difference overall between treatment arms for time-to-heavy-drinking day. However, participants aged 20-29 years who received XR-NTX had a longer time to first heavy drinking day compared to the placebo group (24.1 vs. 9.5days; p<0.001). There were no statistically significant differences between groups for other individual drinking outcomes. A sub-analysis, however, found participants who received ≥4 XR-NTX were more likely (p<0.005) to have improved composite alcohol scores than the placebo group. Post-hoc power analysis revealed that despite the study being powered for HIV outcomes, sufficient power (0.94) was available to distinguish the observed differences.
CONCLUSIONS: Among CJS-involved PLH with AUDs transitioning to the community, XR-NTX lengthens the time to heavy drinking day for younger persons; reduces alcohol consumption when using a composite alcohol consumption score; and is not associated with any serious adverse events.
Fulltext Extended-release Naltrexone Improves Viral Suppression Among Incarcerated Persons Living with HIV and Alcohol use Disorders Transitioning to the Community: Results From a Double-Blind, Placebo-Controlled Trial

Springer SA, Di Paola A, Barbour R, Azar MM, Altice FL

J Acquir Immune Defic Syndr, 2018 09 01;79(1):92-100.
PMID: 29781884 DOI: 10.1097/QAI.0000000000001759

OBJECTIVE: To determine whether extended-release naltrexone (XR-NTX) would improve or maintain viral suppression (VS) among incarcerated individuals with HIV and alcohol use disorders (AUDs) transitioning to the community.
DESIGN: A randomized, double-blind, placebo-controlled trial was conducted among incarcerated individuals with HIV and AUDs transitioning to the community from 2010 through 2016.
METHODS: Eligible participants (N = 100) were randomized 2:1 to receive 6 monthly injections of XR-NTX (n = 67) or placebo (n = 33) starting at release and continued for 6 months. The primary and secondary outcomes were the proportion that maintained or improved VS at <200 and <50 copies per milliliter from baseline to 6 months, respectively, using an intention-to-treat analysis.
RESULTS: Participants allocated to XR-NTX improved VS from baseline to 6 months for <200 copies per milliliter (48.0%-64.2%, P = 0.024) and for <50 copies per milliliter (31.0%-56.7%, P = 0.001), whereas the placebo group did not (<200 copies/mL: 64%-42.4%, P = 0.070; <50 copies/mL: 42.0%-30.3%, P = 0.292). XR-NTX participants were more likely to achieve VS than the placebo group at 6 months (<200 copies/mL: 64.2% vs. 42.4%; P = 0.041; <50 copies/mL: 56.7% vs. 30.3%; P = 0.015). XR-NTX independently predicted VS [<200 copies/mL: adjusted odds ratio (aOR) = 2.68, 95% confidence interval (CI) = 1.01 to 7.09, P = 0.047; <50 copies/mL: aOR = 4.54; 95% CI = 1.43 to 14.43, P = 0.009] as did receipt of ≥3 injections (<200 copies/mL: aOR = 3.26; 95% CI = 1.26 to 8.47, P = 0.010; <50 copies/mL: aOR = 6.34; 95% CI = 2.08 to 19.29, P = 0.001). Reductions in alcohol consumption (aOR = 1.43, 95% CI = 1.03 to 1.98, P = 0.033) and white race (aOR = 5.37, 95% CI = 1.08 to 27.72, P = 0.040) also predicted VS at <50 copies per milliliter.
CONCLUSIONS: XR-NTX improves or maintains VS after release to the community for incarcerated people living with HIV and AUDs.
Fulltext A Robust Framework for Data Generative and Heart Disease Prediction Based on Efficient Deep Learning Models

Sarra RR, Dinar AM, Mohammed MA, Ghani MKA, Albahar MA

Diagnostics (Basel), 2022 Nov 22;12(12).
PMID: 36552906 DOI: 10.3390/diagnostics12122899

Biomarkers including fasting blood sugar, heart rate, electrocardiogram (ECG), blood pressure, etc. are essential in the heart disease (HD) diagnosing. Using wearable sensors, these measures are collected and applied as inputs to a deep learning (DL) model for HD diagnosis. However, it is observed that model accuracy weakens when the data gathered are scarce or imbalanced. Therefore, this work proposes two DL-based frameworks, GAN-1D-CNN, and GAN-Bi-LSTM. These frameworks contain: (1) a generative adversarial network (GAN) and (2) a one-dimensional convolutional neural network (1D-CNN) or bi-directional long short-term memory (Bi-LSTM). The GAN model is utilized to augment the small and imbalanced dataset, which is the Cleveland dataset. The 1D-CNN and Bi-LSTM models are then trained using the enlarged dataset to diagnose HD. Unlike previous works, the proposed frameworks increase the dataset first to avoid the prediction bias caused by the limited data. The GAN-1D-CNN achieved 99.1% accuracy, specificity, sensitivity, F1-score, and 100% area under the curve (AUC). Similarly, the GAN-Bi-LSTM obtained 99.3% accuracy, 99.2% specificity, 99.3% sensitivity, 99.2% F1-score, and 100% AUC. Furthermore, time complexity of proposed frameworks is investigated with and without principal component analysis (PCA). The PCA method reduced prediction times for 61 samples using GAN-1D-CNN and GAN-Bi-LSTM to 68.8 and 74.8 ms, respectively. These results show that it is reliable to use our frameworks for augmenting limited data and predicting heart disease.
A Review: The Antiviral Activity of Cyclic Peptides

Chia LY, Kumar PV, Maki MAA, Ravichandran G, Thilagar S

Int J Pept Res Ther, 2023;29(1):7.
PMID: 36471676 DOI: 10.1007/s10989-022-10478-y

In the design and development of therapeutic agents, macromolecules with restricted structures have stronger competitive edges than linear biological entities since cyclization can overcome the limitations of linear structures. The common issues of linear peptides include susceptibility to degradation of the peptidase enzyme, off-target effects, and necessity of routine dosing, leading to instability and ineffectiveness. The unique conformational constraint of cyclic peptides provides a larger surface area to interact with the target at the same time, improving the membrane permeability and in vivo stability compared to their linear counterparts. Currently, cyclic peptides have been reported to possess various activities, such as antifungal, antiviral and antimicrobial activities. To date, there is emerging interest in cyclic peptide therapeutics, and increasing numbers of clinically approved cyclic peptide drugs are available on the market. In this review, the medical significance of cyclic peptides in the defence against viral infections will be highlighted. Except for chikungunya virus, which lacks specific antiviral treatment, all the viral diseases targeted in this review are those with effective treatments yet with certain limitations to date. Thus, strategies and approaches to optimise the antiviral effect of cyclic peptides will be discussed along with their respective outcomes. Apart from isolated naturally occurring cyclic peptides, chemically synthesized or modified cyclic peptides with antiviral activities targeting coronavirus, herpes simplex viruses, human immunodeficiency virus, Ebola virus, influenza virus, dengue virus, five main hepatitis viruses, termed as type A, B, C, D and E and chikungunya virus will be reviewed herein.
Fulltext Methadone dose at the time of release from prison significantly influences retention in treatment: implications from a pilot study of HIV-infected prisoners transitioning to the community in Malaysia

Wickersham JA, Zahari MM, Azar MM, Kamarulzaman A, Altice FL

Drug Alcohol Depend, 2013 Sep 01;132(1-2):378-82.
PMID: 23414931 DOI: 10.1016/j.drugalcdep.2013.01.005

OBJECTIVE: To evaluate the impact of methadone dose on post-release retention in treatment among HIV-infected prisoners initiating methadone maintenance treatment (MMT) within prison.
METHODS: Thirty HIV-infected prisoners meeting DSM-IV pre-incarceration criteria for opioid dependence were enrolled in a prison-based, pre-release MMT program in Klang Valley, Malaysia; 3 died before release from prison leaving 27 evaluable participants. Beginning 4 months before release, standardized methadone initiation and dose escalation procedures began with 5mg daily for the first week and 5mg/daily increases weekly until 80 mg/day or craving was satisfied. Participants were followed for 12 months post-release at a MMT clinic within 25 kilometers of the prison. Kaplan-Meier survival analysis was used to evaluate the impact of methadone dose on post-release retention in treatment.
FINDINGS: Methadone dose ≥80 mg/day at the time of release was significantly associated with retention in treatment. After 12 months of release, only 21.4% of participants on <80 mg were retained at 12 months compared to 61.5% of those on ≥80 mg (Log Rank χ(2)=(1,26) 7.6, p<0.01).
CONCLUSIONS: Higher doses of MMT at time of release are associated with greater retention on MMT after release to the community. Important attention should be given to monitoring and optimizing MMT doses to address cravings and side effects prior to community re-entry from prisons.
Fulltext Jordanian English language educators' perceived readiness for virtual learning environment

Madanat H, Ab Rashid R, Hashmi UM, Alqaryouti MH, Mohamed M, Al Smadi OA

Heliyon, 2024 Feb 29;10(4):e25766.
PMID: 38370217 DOI: 10.1016/j.heliyon.2024.e25766

Online engagement has assumed a pivotal role within educational pedagogy, particularly during the COVID-19 pandemic. This study delves into the perceptions of Jordanian English language educators regarding their preparedness for online teaching in the post-pandemic landscape. In this quantitative study, a group of 101 English language educators from Jordanian universities participated, and their responses were subjected to analysis through descriptive statistics. The findings of this analysis indicate that the respondents exhibited a moderate level of familiarity with technology and e-learning platforms, alongside a similarly moderate level of competence in managing their online courses. Furthermore, the study underscores a noteworthy gap in their exposure to online education, despite their considerable tenure in teaching English. Consequently, the study underscores the necessity for tailored training programs designed to comprehensively enhance the online teaching proficiency of English language educators, thereby facilitating a more effective virtual learning environment.
Fulltext A case report of a patient with recurrent and severe infections highlighting the importance of considering inborn errors of immunity

Altammar F, Alshamali M, Alqunaee M, Alali AJ, Elshafie RM, Al-Herz W

Front Pediatr, 2024;12:1340367.
PMID: 38487470 DOI: 10.3389/fped.2024.1340367

Inborn errors of immunity (IEI) can often be misdiagnosed early in life due to their heterogenous clinical presentations. Interleukin-1 receptor-associated kinase 4 (IRAK-4) deficiency is one of the rare innate immunodeficiency disorders. We present the case of a patient who presented at the age of 15 days with meningitis and septic shock that responded to antibiotics. She was admitted again at the age of 45 days with pseudomonas aeruginosa bacteremia that was associated with increased inflammatory markers. Her third admission was at the age of 2.5 months due to left sided peri-orbital cellulitis that was again associated with elevated inflammatory markers. At 3.5 months, she experienced left orbital cellulitis, which was complicated by extensive sinus involvement, erosion, and abscess formation in the pterygopalatine fossa. Her condition progressed to septic shock and required multiple antibiotics and surgical interventions for drainage and control of the infection source. Both abscess and blood culture were positive for pseudomonas aeruginosa. An IEI was suspected but basic immunology testing was normal. Whole Exome Sequencing was performed and a novel mutation in IRAK4 was detected. In conclusion, we highlight the importance of raising awareness among pediatricians about the potentially lethal IEI and the need to consult specialists when these diseases are suspected. Among them is IRAK-4 deficiency which can be diagnosed by sophisticated functional assays and/or genetic testing.
Thermal design and zeotropic working fluids mixture selection optimization for a solar waste heat driven combined cooling and power system

Kheimi M, K Salamah S, A Maddah H, Mustafa Al Bakri Abdullah M

Chemosphere, 2023 Sep;335:139036.
PMID: 37245592 DOI: 10.1016/j.chemosphere.2023.139036

Considering the limitation of fossil fuel resources and their environmental effects, the use of renewable energies is increasing. In the current research, a combined cooling and power production (CCPP) system is investigated, the energy source of which is solar energy. Solar energy absorbs by solar flat plate collectors (SFPC). The system produces power with the help of an organic Rankine cycle (ORC). An ejector refrigeration cycle (ERC) system is considered to provide cooling capacity. The motive flow is supplied from the expander extraction in the ERC system. Various working fluids have been applied so far for the ORC-ERC cogeneration system. This research investigates the effect of using two working fluids R-11 and R-2545fa, and the zeotropic mixtures obtained by mixing these two fluids. A multiobjective optimization process is considered to select the appropriate working fluid. In the optimization design process, the goal is to minimize the total cost rate (TCR) and maximize the exergy efficiency of the system. The design variables are the quantity of SFPC, heat recovery vapor generator (HRVG) pressure, ejector motive flow pressure, evaporator pressure, condenser pressure, and entertainment ratio. Finally, it is observed that using zeotropic mixtures obtained from these two refrigerants has a better result than using pure refrigerants. Finally, it is observed that the best performance is achieved when R-11 and R245fa are mixed with a ratio of 80 to 20%, respectively and led to 8.5% improvement in exergy efficiency, while the increase in TCR is only 1.5%.
Fulltext Enhancement of gallium nitride on silicon (111) using pulse atomic-layer epitaxy (PALE) AlN with composition-graded AlGaN buffer

Mansor M, Norhaniza R, Shuhaimi A, Hisyam MI, Omar AZ, Williams A, et al.

Sci Rep, 2023 May 31;13(1):8793.
PMID: 37258537 DOI: 10.1038/s41598-023-35677-5

The ability to configure the optimal buffer layer for GaN growth depends on the knowledge of relaxation processes that occurs during the cooling step while countering the tensile stresses due to the contrast of thermal expansion coefficient between GaN and Si(111) substrate. Here, we inaugurate the pulse atomic-layer epitaxy (PALE) AlN layer to reinforce the buffer layer to achieve a thick GaN epilayer which is crucial for high performance power devices. The characteristics of grown GaN on Si substrate based on PALE AlN thickness of 0 ~ 100 nm are investigated along with microstructural evolution between AlN NL and composition-graded AlGaN buffer layer. PALE AlN layer deposited with an optimum thickness of 50 nm and above was observed to exhibit a highly uniform coalesced GaN epilayer surface with root-mean square (RMS) roughness of 0.512 nm. The thickness of the PALE AlN layer substantially affected the crystallinity of the top GaN epilayer where the lowest value for symmetric (0 0 0 2) and asymmetric (1 0 -1 2) x-ray rocking curve analysis were achieved, indicating the reduction of threading dislocation density in the growth structure. Transition of the E2 (high) peak from the Raman spectrum shows that the strain compression in GaN epilayer is directly proportional to the thickness of the PALE AlN layer.
Protective effect of treatment with black cumin oil on spatial cognitive functions of rats that suffered global cerebrovascular hypoperfusion

Azzubaidi MS, Saxena AK, Talib NA, Ahmed QU, Dogarai BB

Acta Neurobiol Exp (Wars), 2012;72(2):154-65.
PMID: 22810217

The fixed oil of black cumin seeds, Nigella sativa L. (NSO), has shown considerable antioxidant and anti-inflammatory activities. Chronic cerebral hypoperfusion has been linked to neurodegenerative disorders including Alzheimer's disease (AD) and its subsequent cognitive impairment in which oxidative stress and neuroinflammation are the principal culprits. Cerebrovascular hypoperfusion was experimentally achieved by bilateral common carotid arteries occlusion (2VO) in rats. Morris water maze (MWM) test was employed to assess the effects of NSO on spatial cognitive function before and after 2VO intervention. Rats were divided into long-term memory (LTM) and short-term memory (STM) groups, each was further subdivided into 3 subgroups: sham control, untreated 2VO and NSO treated 2VO group. All subgroups were tested with MWM at the tenth postoperative week. Working memory test results for both sham control and NSO treated groups showed significantly lower escape latency time and total distance travelled than untreated 2VO group. Similarly, LTM and STM MWM tests for sham control and NSO treated groups revealed significantly better maze test performance as compared to untreated 2VO group. Sham control and NSO treated 2VO groups demonstrated superior probe memory test performance as compared to untreated 2VO group. The fixed oil of Nigella sativa seeds has demonstrated noticeable spatial cognitive preservation in rats challenged with chronic cerebral hypoperfusion which indicates a promising prospective neuroprotective effect.
Development and validation of the genitourinary syndrome of menopause symptoms and vaginal treatments acceptability questionnaire (GSM-SVTAQ): An electronic patient-reported outcomes measure

Hassanein MM, Huri HZ, Baig K, Abduelkarem AR, Al-Momani M

Int J Gynaecol Obstet, 2024 Feb;164(2):613-623.
PMID: 37702968 DOI: 10.1002/ijgo.15106

OBJECTIVES: To develop and validate an electronic, patient-reported outcomes measure (PROM) specific for genitourinary syndrome of menopause (GSM) patients. The PROM aimed to accurately assess the burden of GSM symptoms, their impact on health-related and sexual quality of life, and the acceptability of vaginal treatments.
METHODS: The study encompassed a comprehensive three-stage approach to the development and validation of the PROM. Initially, during the preliminary design stage, the necessity for a new PROM was recognized, an expert panel was formed, and semi-structured qualitative interviews were carried out with GSM patients. In the second stage, the study used the five-step pre-validation methodology established by Prior et al. to generate and refine the PROM items. The third and final stage encompassed the determination of scale and item content validity indexes to ensure validity. Additionally, the reliability of each construct was evaluated using Cronbach's α.
RESULTS: The resulting PROM was named GSM-SVTAQ (GSM-symptoms and vaginal treatments acceptability questionnaire). It demonstrated excellent validity in assessing symptoms burden, health-related and sexual quality of life, and vaginal treatment acceptability, with high content validity indices and strong internal consistency. The scale content validity indices and Cronbach's α coefficients for the three domains were (0.926, 0.939), (0.875, 0.947), and (0.824, 0.855), respectively.
CONCLUSION: The GSM-SVTAQ stands as the first GSM-specific, valid, and reliable PROM capable of comprehensively measuring the three components of GSM and the acceptability of vaginal treatments. Its implementation has the potential to significantly enhance patient care and outcomes in GSM management.
Salmonella serovars trend in poultry Malaysia from 2011 to 2020

Ibrahim MM, Jusoh MB, Rose FZC, Azami MM, Roslee R

Vet Res Commun, 2024 Jan 19.
PMID: 38238509 DOI: 10.1007/s11259-024-10303-5

Data and geographical trend of Salmonella serovars infecting poultry in Malaysia is limited. In this study, the trend of Salmonella serovars infection was presented for the past ten years from 2011 to 2020 and the predominant serovars were mapped based on geographical distribution. Analysis of passive surveillance data demonstrated a shift of Salmonella serovars that infected poultry in Malaysia. The Salmonella serovars varied within ten years of registered cases with the Veterinary Research Institute, Ipoh, Malaysia involving samples from live and dead birds. Total number of cases found from the year 2011 to 2020 were 391 cases, involving 73 Salmonella serovars with an additional one group of unclassified serovars known as Salmonella spp. Further analysis revealed that eight serovars were found predominant throughout the ten-year period. These included S. Albany, S. Braenderup, S. Brancaster, S. Corvallis, S. Enteritidis, S. Kentucky, S. Typhimurium and S. Weltevreden. Salmonella spp. (Salmonella that is incapable to be identified based on serotyping) were also one of the major groups observed throughout the years. This study could help the authorities to improvise policies for better disease control programs through the establishment of diagnostic tools for rapid Salmonella screening in poultry.

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