On the versatility of graphene-cellulose composites: An overview and bibliometric assessment.

Practical benefits of graphene-cellulose composites (GCC) are categorical. Diverse salient features like thermal and electrical conductivity, mechanical strength, and durability make GCC advantageous for widespread applications. Despite extensive studies the basic understanding of various fundamental aspects of this novel complex remains deficient. Based on this fact, a critical overview and bibliometric analysis involving the overall prospects of GCC was made wherein a total of 1245 research articles from the Scopus database published during the year 2002 to 2020 were used. For the bibliometric assessment, various criteria including the publication outputs, co-authorships, affiliated countries, and co-occurrences of the authors' keywords were explored. Environmental amiability, sustainability, economy, and energy efficiency of GCC were emphasized. In addition, the recent trends, upcoming challenges, and applied interests of GCC were highlighted. The findings revealed that the studies on GCC related to the energy storage, adsorption, sensing, and printing are ever-increasing, indicating the global research drifts on GCC. The bibliometric map analysis displayed that among the researchers from 61 countries/territories, China alone contributed about 50 % of the international publications. It is asserted that the current article may offer taxonomy to navigate into the field of GCC wherein stronger collaboration networks can be established worldwide through integrated research activities desirable for sustainable development.

Uv-vis spectroscopy for simple chloride content analysis in edible oil using charged amino-functionalized carbon quantum dots fluorophore reagent.

The utilization of UV-Vis spectroscopy with amino-functionalized carbon quantum dots (NCQD) as a positive fluorophore reagent for chloride sensing in oil marks a notable advancement in analytical spectroscopy chemistry. This approach streamlines the detection process by eliminating the need for lengthy procedures and pretreatment steps typically associated with chloride detection in edible oil. By incorporating NCQD in chloride detection within the oil matrix, the wavelength analysis transitions from the UV to the visible region. This shift eliminates interference from oil matrix interactions, ensuring more accurate results. Molecular analysis of NCQD reveals significant shifts in its Fourier Transformation Infrared and photoluminescence spectroscopy peaks due to interaction with chloride in edible oil. It has two impressive sensitivity ranges spanning from 0.1-1.0 to 1.0-8.0 ppm, with a value of -0.4656 au. ppm-1 (R2 = 0.998) and -0.0361 au. ppm-1 (R2 = 0.931), respectively, the technique meets regulatory standards while achieving a low limit of detection (LOD) of 0.1 ppm. This places it on par with conventional methods and commercial sensors. The NCQD-UV-Vis spectroscopy method not only enhances the efficiency and accuracy of chloride detection but also holds promise for various industrial applications requiring simple and precise monitoring of chloride levels in oil samples.

Effectiveness of stingless bee (Kelulut) honey versus conventional gel dressing in diabetic wound bed preparation: A randomized controlled trial.

Purpose: Kelulut honey contains trehalulose and has high antioxidant content, such as phenolic and flavonoid substances, which can promote wound healing. This study evaluated the effectiveness of Kelulut honey in diabetic wound healing compared to a commercially available conventional gel dressing (Intrasite gel). Methods: A prospective, randomized, single-blinded control trial was performed on eligible diabetic patients with full-thickness cavity wounds. Patients' demographics, size and site of wounds, and baseline routine blood investigations were recorded. The wounds were dressed every other day with Kelulut honey for the intervention group or gel for the control group. The wound size reduction and granulation tissue formation percentage were calculated every 6 days for 1 month. Results: Seventy-one patients were randomized. After 30 days of follow-up, 62 participants were available for analysis: 30 from the control group and 32 from the treatment group. The control group had increased granulation tissue at baseline and more wounds on the lower limb and posterior trunk. Both groups showed an increasing mean and median percentage of wound epithelialization and granulation tissue over time, with significantly higher values at every timepoint in the honey group (p < 0.05). However, repeated measures analysis of variance and analysis of covariance revealed no significant interaction effect between the different treatments and time, with F (2.02, 121.28) = 0.88, p = 0.417 and F (1.60, 93.95) = 0.79, p = 0.431, respectively. Conclusion: This study revealed that Kelulut honey was comparable to and as effective as the conventional gel in treating diabetic wounds in terms of promoting epithelialization and granulation tissue formation.

Comparing Low Volume Versus Conventional Volume of Polyethylene Glycol for Bowel Preparation during Colonoscopy: A Randomised Controlled Trial.

Background: Polyethylene glycol (PEG) solution is widely used as a colonoscopic bowel cleaning agent, although some patients are intolerant due to the need for ingesting large solution volumes and unpleasant taste. A low-volume solution may enhance patient tolerability and compliance in bowel preparation. Accordingly, this study compared the effectiveness of two difference PEG volumes for bowel preparation before colonoscopy in terms of bowel cleanliness, completeness of colonoscopy, patient tolerability and colonoscopy duration. Methods: Using a prospective randomised controlled single-blinded study design, 164 patients scheduled for colonoscopy were allocated to two groups (n = 82 patients in each) to receive either the conventional PEG volume (3 L, control group) or the low volume (2 L, intervention group). The Boston Bowel Preparation Scale (BBPS), a validated scale for assessing bowel cleanliness during colonoscopy, was used to score bowel cleanliness in three colon segments. Secondarily, colonoscopy completeness, tolerability to drinking PEG and the duration of colonoscopy were compared between the groups. Results: There were no statistically significant differences between the two intervention groups in terms of bowel cleanliness (P = 0.119), colonoscopy completion (P = 0.535), tolerability (P = 0.190) or the amount of sedation/analgesia required (midazolam, P = 0.162; pethidine, P = 0.708). Only the duration of colonoscopy differed between the two groups (longer duration in the control group, P = 0.039). Conclusion: Low-volume (2 L) PEG is as effective as the standard 3 L solution in bowel cleaning before colonoscopy; however, the superiority of either solution could not be established.

The effect of pre-endoscopy maltodextrin beverage on gastric residual volume and patient's well-being: a randomised controlled trial.

Prolonged fasting prior to oesophagogastroduodenoscopy (OGDS) could be noxious to patients' well-being. Strict fasting protocol has been used prior to OGDS with the concern of reduced visibility or suboptimal endoscopic assessment. Maltodextrin beverages were also commonly used as the pre-operative carbohydrate loading in enhanced recovery after surgery (ERAS) protocol. Our study aimed to look for the effects of maltodextrin beverage 2 h before OGDS on gastric residual volume and patient's well-being scores. This was a single-blinded, stratified randomised controlled trial, comparing control group (A, received 400 ml of plain water) and carbohydrate loading group (B, received 400 ml of Carborie). The primary objectives were to measure the gastric residual volume (GRV) and patient's well-being scores using visual analogue scale (VAS) scores for hunger, thirst, anxiety, tiredness and general discomfort. Of 80 randomised patients, 78 completed the study (38 received plain water and 40 Carborie). The median (IQR) GRV was not significantly different between group A and B (5.0 ml (20) vs 4.0 ml (19), p = 0.777). Both groups showed significant reduction in VAS scores in all five parameters (p ≤ 0.001). There were no complications attributed to endoscopy in either group. Pre-endoscopy maltodextrin beverage is as safe as clear water with improved patient's well-being in both groups.Clinical Trial Registration: NCT05106933.

All silicon MIR super absorber using fractal metasurfaces.

Perfect absorbers can be used in photodetectors, thermal imaging, microbolometers, and thermal photovoltaic solar energy conversions. The spectrum of Mid-infrared (MIR) wavelengths offers numerous advantages across a wide range of applications. In this work, we propose a fractal MIR broadband absorber which is composed of three layers: metal, dielectric, and metal (MDM), with the metal being considered as n-type doped silicon (D-Si) and the dielectric is silicon carbide (SiC). The architectural design was derived from the Sierpinski carpet fractal, and different building blocks were simulated to attain optimal absorption. The 3D finite element method (FEM) approach using COMSOL Multiphysics software is used to obtain numerical results. The suggested fractal absorber exhibits high absorption enhancement for MIR in the range between 3 and 9 µm. D-Si exhibits superior performance compared to metals in energy harvesting applications that utilize plasmonics at the mid-infrared range. Typically, semiconductors exhibit rougher surfaces than noble metals, resulting in lower scattering losses. Moreover, silicon presents various advantages, including compatibility with complementary metal-oxide-semiconductor (CMOS) and simple manufacturing through conventional silicon fabrication methods. In addition, the utilization of doped silicon material in the mid-IR region facilitates the development of microscale integrated plasmonic devices.

A decade of amphibian studies (Animalia, Amphibia) at Sekayu lowland forest, Hulu Terengganu, Peninsular Malaysia.

Amphibians of Sekayu lowland forest have been studied more than a decade, with discoveries of new records of species showing no sign of abating between the years 2003 to 2020, indicating the remarkably rich diversity of anurans in this forest. Despite ceaseless anthropogenic activities in this area, this study successfully recorded 52 species of amphibians from 32 genera in the lowland forest of Sekayu. The species composition consisted of a single species from the family Ichthyophiidae and 51 species of anurans of 31 genera and six families. The number of species recorded has steadily increased especially during more recent surveys from 2015 to 2020. This study augments the total number of amphibian species recorded from Hulu Terengganu by ten additional species, increasing the total to 70 species for the district.

Nanosizing Approach-A Case Study on the Thermal Decomposition of Hydrazine Borane.

Hydrazine borane (HB) is a chemical hydrogen storage material with high gravimetric hydrogen density of 15.4 wt%, containing both protic and hydridic hydrogen. However, its limitation is the formation of unfavorable gaseous by-products, such as hydrazine (N2H4) and ammonia (NH3), which are poisons to fuel cell catalyst, upon pyrolysis. Previous studies proved that confinement of ammonia borane (AB) greatly improved the dehydrogenation kinetics and thermodynamics. They function by reducing the particle size of AB and establishing bonds between silica functional groups and AB molecules. In current study, we employed the same strategy using MCM-41 and silica aerogel to investigate the effect of nanosizing towards the hydrogen storage properties of HB. Different loading of HB to the porous supports were investigated and optimized. The optimized loading of HB in MCM-41 and silica aerogel was 1:1 and 0.25:1, respectively. Both confined samples demonstrated great suppression of melting induced sample foaming. However, by-products formation was enhanced over dehydrogenation in an open system decomposition owing to the presence of extensive Si-O···BH3(HB) coordination that further promote the B-N bond cleavage to release N2H4. The Si-OH···N(N2H4) hydrogen bonding may further promote N-N bond cleavage in the resulting N2H4, facilitating the formation of NH3. As temperature increases, the remaining N-N-B oligomeric chains in the porous silica, which are lacking the long-range structure may further undergo intramolecular B-N or N-N cleavage to release substantial amount of N2H4 or NH3. Besides open system decomposition, we also reported a closed system decomposition where complete utilization of the N-H from the released N2H4 and NH3 in the secondary reaction can be achieved, releasing mainly hydrogen upon being heated up to high temperatures. Nanosizing of HB particles via PMMA encapsulation was also attempted. Despite the ester functional group that may favor multiple coordination with HB molecules, these interactions did not impart significant change towards the decomposition of HB selectively towards dehydrogenation.

The ChoCO-W prospective observational global study: Does COVID-19 increase gangrenous cholecystitis?

BACKGROUND: The incidence of the highly morbid and potentially lethal gangrenous cholecystitis was reportedly increased during the COVID-19 pandemic. The aim of the ChoCO-W study was to compare the clinical findings and outcomes of acute cholecystitis in patients who had COVID-19 disease with those who did not. METHODS: Data were prospectively collected over 6 months (October 1, 2020, to April 30, 2021) with 1-month follow-up. In October 2020, Delta variant of SARS CoV-2 was isolated for the first time. Demographic and clinical data were analyzed and reported according to the STROBE guidelines. Baseline characteristics and clinical outcomes of patients who had COVID-19 were compared with those who did not. RESULTS: A total of 2893 patients, from 42 countries, 218 centers, involved, with a median age of 61.3 (SD: 17.39) years were prospectively enrolled in this study; 1481 (51%) patients were males. One hundred and eighty (6.9%) patients were COVID-19 positive, while 2412 (93.1%) were negative. Concomitant preexisting diseases including cardiovascular diseases (p < 0.0001), diabetes (p < 0.0001), and severe chronic obstructive airway disease (p = 0.005) were significantly more frequent in the COVID-19 group. Markers of sepsis severity including ARDS (p < 0.0001), PIPAS score (p < 0.0001), WSES sepsis score (p < 0.0001), qSOFA (p < 0.0001), and Tokyo classification of severity of acute cholecystitis (p < 0.0001) were significantly higher in the COVID-19 group. The COVID-19 group had significantly higher postoperative complications (32.2% compared with 11.7%, p < 0.0001), longer mean hospital stay (13.21 compared with 6.51 days, p < 0.0001), and mortality rate (13.4% compared with 1.7%, p < 0.0001). The incidence of gangrenous cholecystitis was doubled in the COVID-19 group (40.7% compared with 22.3%). The mean wall thickness of the gallbladder was significantly higher in the COVID-19 group [6.32 (SD: 2.44) mm compared with 5.4 (SD: 3.45) mm; p < 0.0001]. CONCLUSIONS: The incidence of gangrenous cholecystitis is higher in COVID patients compared with non-COVID patients admitted to the emergency department with acute cholecystitis. Gangrenous cholecystitis in COVID patients is associated with high-grade Clavien-Dindo postoperative complications, longer hospital stay and higher mortality rate. The open cholecystectomy rate is higher in COVID compared with non -COVID patients. It is recommended to delay the surgical treatment in COVID patients, when it is possible, to decrease morbidity and mortality rates. COVID-19 infection and gangrenous cholecystistis are not absolute contraindications to perform laparoscopic cholecystectomy, in a case by case evaluation, in expert hands.

Plasmonic Biosensors: Review.

Biosensors have globally been considered as biomedical diagnostic tools required in abundant areas including the development of diseases, detection of viruses, diagnosing ecological pollution, food monitoring, and a wide range of other diagnostic and therapeutic biomedical research. Recently, the broadly emerging and promising technique of plasmonic resonance has proven to provide label-free and highly sensitive real-time analysis when used in biosensing applications. In this review, a thorough discussion regarding the most recent techniques used in the design, fabrication, and characterization of plasmonic biosensors is conducted in addition to a comparison between those techniques with regard to their advantages and possible drawbacks when applied in different fields.

Serotonin transporter in the temporal lobe, hippocampus and amygdala in SUDEP.

Several lines of evidence link deficient serotonin function and SUDEP. Chronic treatment with serotonin reuptake inhibitors (SRIs) reduces ictal central apnoea, a risk factor for SUDEP. Reduced medullary serotonergic neurones, modulators of respiration in response to hypercapnia, were reported in a SUDEP post-mortem series. The amygdala and hippocampus have high serotonergic innervation and are functionally implicated in seizure-related respiratory dysregulation. We explored serotonergic networks in mesial temporal lobe structures in a surgical and post-mortem epilepsy series in relation to SUDEP risk. We stratified 75 temporal lobe epilepsy patients with hippocampal sclerosis (TLE/HS) into high (N = 16), medium (N = 11) and low risk (N = 48) groups for SUDEP based on generalised seizure frequency. We also included the amygdala in 35 post-mortem cases, including SUDEP (N = 17), epilepsy controls (N = 10) and non-epilepsy controls (N = 8). The immunohistochemistry labelling index (LI) and axonal length (AL) of serotonin transporter (SERT)-positive axons were quantified in 13 regions of interest with image analysis. SERT LI was highest in amygdala and subiculum regions. In the surgical series, higher SERT LI was observed in high risk than low risk cases in the dentate gyrus, CA1 and subiculum (p < 0.05). In the post-mortem cases higher SERT LI and AL was observed in the basal and accessory basal nuclei of the amygdala and peri-amygdala cortex in SUDEP compared to epilepsy controls (p < 0.05). Patients on SRI showed higher SERT in the dentate gyrus (p < 0.005) and CA4 (p < 0.05) but there was no difference in patients with or without a psychiatric history. Higher SERT in hippocampal subfields in TLE/HS cases with SUDEP risk factors and higher amygdala SERT in post-mortem SUDEP cases than epilepsy controls supports a role for altered serotonergic networks involving limbic regions in SUDEP. This may be of functional relevance through reduced 5-HT availability.

Morris water maze: a versatile and pertinent tool for assessing spatial learning and memory.

Since its development about 40 years ago (1981-2021), Morris water maze has turned into a very popular tool for assessing spatial learning and memory. Its many advantages have ensured its pertinence to date. These include its effectiveness in evaluating hippocampal-dependent learning and memory, exemption from motivational differences across diverse experimental manipulations, reliability in various cross-species studies, and adaptability to many experimental conditions with various test protocols. Nonetheless, throughout its establishment, several experimental and analysis loopholes have galvanized researchers to assess ways in which it could be improved and adapted to fill this gap. Therefore, in this review, we briefly summarize these developments since the early years of its establishment through to the most recent advancements in computerized analysis, offering more comprehensive analysis paradigms. In addition, we discuss the adaptability of the Morris water maze across different test versions and analysis paradigms, providing suggestions with regard to the best paradigms for particular experimental conditions. Hence, the proper selection of the experimental protocols, analysis paradigms, and consideration of the assay's limitations should be carefully considered. Given that appropriate measures are taken, with various adaptations made, the Morris water maze will likely remain a relevant tool to assess the mechanisms of spatial learning and memory.

Three-Phase Six-Level Multilevel Voltage Source Inverter: Modeling and Experimental Validation.

This research proposes a three-phase six-level multilevel inverter depending on twelve-switch three-phase Bridge and multilevel DC-link. The proposed architecture increases the number of voltage levels with less power components than conventional inverters such as the flying capacitor, cascaded H-bridge, diode-clamped and other recently established multilevel inverter topologies. The multilevel DC-link circuit is constructed by connecting three distinct DC voltage supplies, such as single DC supply, half-bridge and full-bridge cells. The purpose of both full-bridge and half-bridge cells is to provide a variable DC voltage with a common voltage step to the three-phase bridge's mid-point. A vector modulation technique is also employed to achieve the desired output voltage waveforms. The proposed inverter can operate as a six-level or two-level inverter, depending on the magnitude of the modulation indexes. To guarantee the feasibility of the proposed configuration, the proposed inverter's prototype is developed, and the experimental results are provided. The proposed inverter showed good performance with high efficiency of 97.59% following the IEEE 1547 standard. The current harmonics of the proposed inverter was also minimized to only 5.8%.

18F-labeled Bisphosphonate as an Alternative Candidate to the Gold Standard[18F]sodium fluoride ([18F]NaF) for PET Bone Imaging.

Bone metastases are a common source of malignancy in the skeleton and occur much more often than primary bone cancer. Several works were being performed to identify early markers for bone metastasis and novel drug targets to improve patients' quality of life. As some concerns exist with the [18F]sodiumfluoridein positron emission tomography (PET) bone imaging, there has been an increase in the number of targeted radiopharmaceutical markers for bone metastases imaging in its competitor, 68Ga. Since 18F properties are superior to those of 68Ga, there is a distinct motivation for developing 18F radiopharmaceuticals for bone metastases imaging.

Analytical GC-FID Method for the Determination of Organic Solvents in Radiopharmaceuticals.

BACKGROUND: Organic solvents play an indispensable role in most of the radiopharmaceutical production stages. It is almost impossible to remove them entirely in the final formulation of the product. OBJECTIVE: In this presented work, an analytical method by gas chromatography coupled with flame ionization detection (GC-FID) has been developed to determine organic solvents in radiopharmaceutical samples. The effect of injection holding time, temperature variation in the injection port, and the column temperature on the analysis time and resolution (R ≥ 1.5) of ethanol and acetonitrile was studied extensively. METHODS: The experimental conditions were optimized with the aid of further statistical analysis; thence, the proposed method was validated following the International Council for Harmonisation (ICH) Q2 (R1) guideline. RESULTS: The proposed analytical method surpassed the acceptance criteria including the linearity > 0.990 (correlation coefficient of R2), precision < 2%, LOD, and LOQ, accuracy > 90% for all solvents. The separation between ethanol and acetonitrile was acceptable with a resolution R > 1.5. Further statistical analysis of Oneway ANOVA revealed that the increment in injection holding time and variation of temperature at the injection port did not significantly affect the analysis time. Nevertheless, the variation in injection port temperature substantially influenced the resolution of ethanol and acetonitrile peaks (p < 0.05). CONCLUSION: The proposed analytical method has been successfully implemented to determine the organic solvent in the [18F]fluoro-ethyl-tyrosine ([18F]FET), [18F]fluoromisonidazole ([18F]FMISO), and [18F]fluorothymidine ([18F]FLT).

Preparation and characterization of nanosized lignin from oil palm (Elaeis guineensis) biomass as a novel emulsifying agent.

A study was carried out to determine the effectiveness of lignin, extracted from oil palm (Elaeis guineensis) biomass as water-in-oil (W/O) emulsifying agent. To achieve this goal, soda lignin (SL) was extracted via soda pulping process and a series of nanosized soda lignin (NSL) were prepared using homogenizer at three different speed i.e. 10,400 rpm (NSL 10), 11,400 rpm (NSL 11) and 12,400 rpm (NSL 12) for one hour. All prepared samples were characterized by FT-IR, UV-Vis spectroscopy, thermogravimetric analysis (TGA), zeta potential analyser, Transmission Electron Microscope (TEM) and Extreme High Resolution Field Emission Scanning Electron Microscope (XHR-FESEM). The result of FTIR showed that there is no prominent change occurred in spectra of all samples while a good stability was reflected by TGA curves. The percentage of creaming index and visual observations of all samples demonstrated that NSL 12 and dosage 2 g (out of 1 g, 1.5 g and 2 g) were found to be the best among all samples. Furthermore, the results of IFT indicate that NSL 12 was proven to be more stable than the commercial product. Therefore, NSL 12 is selected for toxicological studies and was found safe in both, in vitro and in vivo studies.

Morphological Diversity of Gracilaria blodgettii Harvey 1853 (Gracilariaceae, Rhodophyta) from Sarawak, Malaysian Borneo.

Gracilaria red algae are notable for their economic importance as agrophytes, sold as salad vegetable, and used as the base for selected food and nonalcoholic beverages. A wild population of Gracilaria exists in coastal areas of Sarawak, Malaysian Borneo, but there is only limited knowledge on species diversity and its abundance leaving the untapped economic potential of this resource. This study was carried out to determine diversity of wild Gracilaria populations in Lawas, Santubong, and Asajaya, Sarawak, using the combination of morphological character examination and 5' region of the mitochondrial cytochrome c oxidase 1 (CO1-5P) gene analysis. Identification of the species using morphological characters revealed three species, namely, Gracilaria changii, G. blodgettii, and G. arcuata, had been collected from the sampling sites. However, based on 672 bp CO1-5P gene sequence analysis, all the three species were identified as G. blodgettii; besides, low genetic divergence values (0.17%-0.34%) were scored between samples in this study with the same species in GenBank. In the phylogenetic trees, all samples in this study group together with other G. blodgettii have high bootstrap values; thus, this species is monophyletic. This study implies that species identification of Gracilaria and other seagrass taxa which have a phenotypic plasticity problem should include the CO1-5P gene analysis as it is a reliable gene marker for species diversity assessment.

Transmission-enabled fiber Fabry-Perot cavity based on a deeply etched slotted micromirror.

In this work, we report the analysis, fabrication, and characterization of an optical cavity built using a Bragg-coated fiber (BCF) mirror and a metal-coated microelectromechanical systems (MEMS) slotted micromirror, where the latter allows transmission output from the cavity. Theoretical modeling, using Fourier optics analysis for the cavity response based on tracing the propagation of light back and forth between the mirrors, is presented. Detailed simulation analysis is carried out for the spectral response of the cavity under different design conditions. MEMS chips of the slotted micromirror are fabricated using deep reactive ion etching of a silicon-on-insulator substrate with different device-etching depths of 150 µm and 80 µm with aluminum and gold metal coating, respectively. The cavity is characterized as an optical filter using a BCF with reflectivity that is larger than 95% in a 300 nm range across the E-band and the L-band. Versatile filter characteristics were obtained for different values of the MEMS micromirror slit width and cavity length. A free spectral range (FSR) of about 33 nm and a quality factor of about 196 were obtained for a 5.5 µm width aluminum slit, while an FSR of about 148 nm and a quality factor of about 148 were obtained for a 1.5 µm width gold slit. The presented structure opens the door for wide spectral response transmission-type MEMS filters.

Morphological Characteristics and Habitats of Red Seaweed Gracilaria spp. (Gracilariaceae, Rhodophyta) in Santubong and Asajaya, Sarawak, Malaysia.

Red seaweed Gracilaria, one of the largest genus in Division Rhodophyta inhabits Sarawak coastal water. This study was designed to identify the species of Gracilaria using morphological approach and to assess selected water quality parameters in Gracilaria habitats. Three field samplings were carried out in Santubong and Asajaya, Sarawak from November 2013 to December 2014. Overall, three species were identified namely Gracilaria changii, G. blodgettii and G. coronopifolia, attached to net of cage culture in Santubong and root of mangrove trees in Asajaya. In addition, three different taxa of aquatic macroinvertebrates (polychaete, small crab, bivalve) and single species of red seaweed (Acanthophora sp.) were observed in Gracilaria assemblages. An estimate of 37% to 40% of the upper part of the cage net in Santubong was covered by seaweeds and only 16% to 20% in Asajaya's mangrove. The study had provided better information on identification of Gracilaria and their habitat in Sarawak. Future work involving DNA barcoding of each species is in progress.

Kinetic investigation and lifetime prediction of Cs-NIPAM-MBA-based thermo-responsive hydrogels.

This study attempted to clarify the influence of a cross-linker, N,N-methylenebisacrylamide (MBA), and N-isopropylacrylamide (NIPAM) on the non-isothermal kinetic degradation, solid state and lifetime of hydrogels using the Flynn-Wall-Ozawa (F-W-O), Kissinger, and Coats-Redfern (C-Red) methods. The series of dual-responsive Cs-PNIPAM-MBA microgels were synthesized by soapless-emulsion free radical copolymerization in an aqueous medium at 70 °C. The thermal properties were investigated using thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) under nitrogen atmosphere. The apparent activation energy using the chosen Flynn-Wall-Ozawa and Kissinger methods showed that they fitted each other. Meanwhile, the type of solid state mechanism was determined using the Coats-Redfern method proposed for F1 (pure Cs) and F2 (Cs-PNIPAM-MBA hydrogel series) types, which comprise random nucleation with one nucleus reacting on individual particles, and random nucleation with two nuclei reacting on individual particles, respectively. On average, a higher Ea was attributed to the greater cross-linking density of the Cs hydrogel.