Linearization of wavelength sweeping lasers for the construction of 4-D FMCW LiDAR images of slow-moving objects using baseband beat note signals.

A FMCW LiDAR system of both the distributed feedback laser and external cavity laser is established in baseband beat notes, rather than up-conversion to an intermediate frequency to exclude flicker noise. Meanwhile, utilizing fast-scanning MEMS mirrors, high-quality real-time (1 fps) 4-D images of the slow-moving object (10 mm/s) can be directly constructed at the baseband with a central frequency as low as 100 kHz and a small Doppler shift. The proposed LiDAR architecture based on such a low-frequency baseband significantly improves the optical power budget on the transmitter side and eliminates the costly high-speed sampling circuits on the receiver side.

Antibiotic prescribing and bacterial infection in COVID-19 inpatients in Southeast Asia: a systematic review and meta-analysis.

Background: The prescribing of antibiotics to treat COVID-19 patients has been observed to occur frequently, often without clear justification. This trend raises concerns that it may have exacerbated antimicrobial resistance (AMR). Despite longstanding concerns over AMR in Southeast Asian countries, data on this issue are notably lacking. Objectives: To explore the impact of COVID-19 on antibiotic prescribing, bacterial infection prevalence and common resistant pathogens in COVID-19 inpatients. Methods: We searched PubMed, EMBASE, Web of Science and ThaiJO (a Thai academic database) to identify studies conducted in ASEAN member countries and published between December 2019 and March 2023. Screening and data extraction were done by two independent reviewers, with results synthesized using random-effects meta-analyses and descriptive statistical analyses. This review was registered with PROSPERO (CRD42023454337). Results: Of the 29 studies (19 750 confirmed COVID-19 cases) included for final analysis, the antibiotic prescribing rate was 62.0% (95%CI: 46.0%-76.0%) with a prescribing rate of 58.0% (21.0%-91.0%) in mild/moderate cases versus 91.0% (82.0%-98.0%) in severe/critical cases. Notably, 80.5% of antibiotics prescribed fall under the WHO AWaRe 'Watch' list, followed by 'Access' at 18.4% and 'Reserve' at 1.0%. The reported bacterial infection prevalence was 16.0% (7.0%-29.0%), with Acinetobacter baumannii being the most common resistant bacterium at 7.7%. Singapore was notable for its lower antibiotic prescribing rate of 17.0% and a lower bacterial infection rate of 10.0%. Conclusions: High antibiotic prescribing rates, disproportionate to bacterial infections and varying practices for COVID-19 inpatients across countries highlight the urgent need for this region to collaborate to tackle and mitigate AMR.

Compact and broadband silicon polarization splitter-rotator using adiabaticity engineering.

We propose and demonstrate a short and broadband silicon mode-conversion polarization splitter-rotator (PSR) consisting of a mode-conversion taper and an adiabatic coupler-based mode sorter both optimized by adiabaticity engineering (AE). AE is used to optimize the distribution of adiabaticity parameter over the length of the PSR, providing shortcut to adiabaticity at a shorter device length. The total length of the PSR is 85 µm. The design is compatible with standard silicon photonics platforms and requires only one patterning step. Fabricated PSR has a polarization cross talk of less than -20 dB over the entire O-band for the TE polarization and a polarization cross talk of less than -15 dB from 1267 to 1348 nm for the TM polarization. Overall, the PSR shows low polarization cross talk (-15 dB) over a bandwidth of 81 nm in the O-band. Cross-wafer measurements show that the PSR has good fabrication tolerance.

Examining the relationship between personality traits, work experience, burnout, and intention to stay among home care aides in Taiwan.

BACKGROUND: Home care aides play an important role in providing long-term care services, but there is currently an insufficient supply of workers to meet the growing demand in Taiwan due to the increasing number of older adults and people with disabilities requiring care. There are numerous factors that influence the retention of home care aides. Previous research has indicated that taking employees' individual personalities into account can enhance task delegation and organizational efficiency within an organization. Severe occupational burnout is likely to diminish vitality and disrupt sleep, which, in turn, can result in higher employee turnover rates. To date, no research has explored the correlation between personality traits, burnout, work experience, and the retention of home care aides. Given these gaps in knowledge, the present study aims to investigate how personality traits and occupational burnout are associated with the intention to stay among home care aides in Taiwan. METHODS: The study was a cross-sectional survey that utilized purposive sampling to interview 285 home care aides in Hualien County from December 2020 to January 2021. A self-report questionnaire, administered with informed consent, was used to collect data on demographics, work experience, occupational burnout, personality, and intention to stay. The researchers utilized hierarchical regression analysis to analyze the data. All measurements exhibited high reliability and consistency, with Cronbach's α values ranging from 0.8 to 0.9. RESULTS: The subscales for personal burnout, work-related burnout, and client-related burnout, along with all personality scales, were highly correlated with intention to stay, except for the openness trait (p < .05). Moreover, married, full-time employment, satisfied with the promotion system and current job as home care aides on the whole, lower levels of work-related burnout, and agreeable personality type were found to be significant predictors for intention to stay (p < .05) , and the adjusted R2 of the model was 29.4%. CONCLUSIONS: This study has concluded that using personality traits as a criterion to select home care aides with a high level of agreeableness prior to recruitment, enhancing the professionalism and comprehensive of promotion system, and reducing work burnout are measures that may help home care service providers increase the intention to stay among home care aides.

Aquaporin 4 Expression Level Is Decreased in Skeletal Muscles with Aging.

Skeletal muscle is a tissue that contains abundant water. However, by aging a decrease in muscle water content is induced in skeletal muscles, which is one of major age-related alterations in skeletal muscles as common as muscle atrophy. Selective water channel aquaporin 4 (AQP4) is one of major water transport networks in the skeletal muscles. However, the effects of aging on water transport via AQP4 in skeletal muscles remain unclear. Thus, the current study investigated the change of the expression level of AQP4 in the aged skeletal muscles. Eight-week-old (the young group) and 2-year-old (the old group) female Fischer 344 rats were used in this study (n = 6/group). In skeletal muscles of each group, the expression levels of some target proteins were quantified by Western blot analysis. As a result, the relative muscle weight in the old group was significantly decreased, compared with that in the young group (p < 0.05). The decline in the muscle water content was accompanied by the decrease in expression of AQP4 in the aged skeletal muscles (p < 0.05, respectively). Moreover, the expression of transient receptor potential vanilloid 4, which synergistically regulates the osmolality together with AQP4, was significantly reduced in the aged skeletal muscles (p < 0.05). Therefore, the current study suggested that water transport abilities via AQP4 may decrease in the aged skeletal muscles, and thereby may be involved in age-related loss of muscle water content.

IL-4 Signaling Promotes Myoblast Differentiation and Fusion by Enhancing the Expression of MyoD, Myogenin, and Myomerger.

Myoblast fusion is essential for skeletal muscle development, growth, and regeneration. However, the molecular mechanisms underlying myoblast fusion and differentiation are not fully understood. Previously, we reported that interleukin-4 (IL-4) promotes myoblast fusion; therefore, we hypothesized that IL-4 signaling might regulate the expression of the molecules involved in myoblast fusion. In this study, we showed that in addition to fusion, IL-4 promoted the differentiation of C2C12 myoblast cells by inducing myoblast determination protein 1 (MyoD) and myogenin, both of which regulate the expression of myomerger and myomaker, the membrane proteins essential for myoblast fusion. Unexpectedly, IL-4 treatment increased the expression of myomerger, but not myomaker, in C2C12 cells. Knockdown of IL-4 receptor alpha (IL-4Rα) in C2C12 cells by small interfering RNA impaired myoblast fusion and differentiation. We also demonstrated a reduction in the expression of MyoD, myogenin, and myomerger by knockdown of IL-4Rα in C2C12 cells, while the expression level of myomaker remained unchanged. Finally, cell mixing assays and the restoration of myomerger expression partially rescued the impaired fusion in the IL-4Rα-knockdown C2C12 cells. Collectively, these results suggest that the IL-4/IL-4Rα axis promotes myoblast fusion and differentiation via the induction of myogenic regulatory factors, MyoD and myogenin, and myomerger.

Beekeeping in Europe facing climate change: A mixed methods study on perceived impacts and the need to adapt according to stakeholders and beekeepers.

The beekeeping sector is suffering from the detrimental effects of climate change, both directly and indirectly. Despite numerous studies conducted on this subject, large-scale research incorporating stakeholders' and beekeepers' perspectives has remained elusive. This study aims to bridge this gap by assessing the extent to which stakeholders involved in the European beekeeping sector and European beekeepers perceive and experience the impacts of climate change on their operations, and whether they had to adapt their practices accordingly. To this end, a mixed-methods study including in-depth stakeholder interviews (n = 41) and a pan-European beekeeper survey (n = 844) was completed within the frame of the EU-funded H2020-project B-GOOD. The development of the beekeeper survey was informed by insights from literature and the stakeholder interviews. The results highlighted significant regional disparities in the perceived impacts of climate change, with beekeepers in Southern European regions expressing more negative outlooks, while Northern European beekeepers reported more favourable experiences. Furthermore, survey analysis revealed beekeepers who were classified as 'heavily impacted' by climate change. These beekeepers reported lower average honey yields, higher colony winter loss rates and a stronger perceived contribution of honey bees to pollination and biodiversity, underscoring climate change's detrimental impacts on the beekeeping sector. Multinomial logistic regression revealed determinants of the likelihood of beekeepers being classified as 'heavily impacted' by climate change. This analysis indicates that Southern European beekeepers experienced a 10-fold likelihood of being classified as heavily impacted by climate change compared to Northern European beekeepers. Other significant factors distinguishing 'winners' and 'losers' were self-reported level of professionalism as a beekeeper (ranging from pure hobbyist to fully professional, Odds Ratio (OR) = 1.31), number of years active in beekeeping (OR = 1.02), availability of floral resources throughout the bee season (OR = 0.78), beehives located in a forested environment (OR = 1.34), and the presence of local policy measures addressing climate change-related challenges (OR = 0.76).

Optimization of dye-contaminated wastewater treatment by fungal Mycelial-light expanded clay aggregate composite.

Dye-contaminated wastewaters from the printing batik industry are hazardous if discharged into the environment without any treatment. Finding an optimization and reusability assessment of a new fungal-material composite for dye-contaminated wastewater treatment is important for efficiency. The study purposes to optimize fungal mycelia Trametes hirsuta EDN 082 - light expanded clay aggregate (myco-LECA) composite for real priting batik dye wastewater treatment by using Response Surface Methodology with Central Composite Design (RSM-CCD). The factors included myco-LECA weight (2-6 g), wastewater volume (20-80 mL), and glucose concentration (0-10%) were applied for 144 h of incubation time. The result showed that the optimum condition was achieved at 5.1 g myco-LECA, at 20 mL wastewater, and at 9.1% glucose, respectively. In this condition, the decolorization values with an incubation time of 144 h were 90, 93, and 95%, at wavelengths 570, 620, and 670 nm, respectively. A reusability assessment was conducted for 19 cycles and the result showed that decolorization effectiveness was still above 96%. GCMS analysis showed the degradation of most compounds in the wastewater and the degradation products of the wastewater demonstrated detoxification against Vigna radiata and Artemia salina. The study suggests that myco-LECA composite has a good performance and therefore is a promising method for the treatment of printing batik wastewater.

Enhancing the Biological Oxidation of H2S in a Sewer Pipe with Highly Conductive Concrete and Electricity-Producing Bacteria.

Hydrogen sulfide (H2S) generated in sewer systems is problematic to public health and the environment, owing to its corrosive consequences, odor concerns, and poison control issues. In a previous work, conductive concrete, based on amorphous carbon with a mechanism that operates as a microbial fuel cell was investigated. The objective of the present study is to develop additional materials for highly conductive concrete, to mitigate the concentration of H2S in sewer pipes. Adsorption experiments were conducted to elucidate the role of the H2S reduction. Additionally, electricity-producing bacteria (EPB), isolated from a municipal wastewater treatment plant, were inoculated to improve the H2S reduction. The experimental results showed that inoculation with EPB could decrease the concentration of H2S, indicating that H2S was biologically oxidized by EPB. Several types of new materials containing acetylene black, or magnetite were discovered for use as conductive concrete, and their abilities to enhance the biological oxidation of H2S were evaluated. These conductive concretes were more effective than the commercial conductive concrete, based on amorphous carbon, in decreasing the H2S concentration in sewer pipes.

Influence of Salts on the Photocatalytic Degradation of Formic Acid in Wastewater.

Conventional wastewater treatment technologies have difficulties in feasibly removing persistent organics. The photocatalytic oxidation of these contaminants offers an economical and environmentally friendly solution. In this study, TiO2 membranes and Ag/TiO2 membranes were prepared and used for the decomposition of dissolved formic acid in wastewater. The photochemical deposition of silver on a TiO2 membrane improved the decomposition rate. The rate doubled by depositing ca. 2.5 mg of Ag per 1 g of TiO2. The influence of salinity on formic acid decomposition was studied. The presence of inorganic salts reduced the treatment performance of the TiO2 membranes to half. Ag/TiO2 membranes had a larger reduction of ca. 40%. The performance was recovered by washing the membranes with water. The anion adsorption on the membrane surface likely caused the performance reduction.

Influence of oestrogen on satellite cells and myonuclear domain size in skeletal muscles following resistance exercise.

BACKGROUND: Oestrogen deficiency reduces skeletal muscle mass and force generation in postmenopausal women. Muscle mass is maintained by satellite cells, which are regulated by oestrogen. Although oestrogen therapy enhances muscle hypertrophy induced by resistance training in postmenopausal women, the molecular mechanism is unclear. METHODS: Adult female rats (10 weeks old) were divided into six groups: sham sedentary (Sham-Sed), sham climbing training (Sham-CT), ovariectomy sedentary (OVX-Sed), ovariectomy climbing training (OVX-CT), ovariectomy plus oestrogen treatment sedentary (OVX+E-Sed), and ovariectomy plus oestrogen treatment climbing training (OVX+E-CT). At 8 weeks after ovariectomy, rats in the training group were trained (one session every 3 days for 8 weeks) to climb a ladder while bearing a load. Oestrogen treatment involved subcutaneous insertion of a 17ß-oestradiol pellet. After 8 weeks, the flexor hallucis longus muscle was collected and analysed. RESULTS: Following climbing training, the flexor hallucis longus muscle mass and muscle-to-body weight ratios were dramatically increased by training (main effect of training, P < 0.01); the OVX+E-CT group showed the highest values (main effect of group, P < 0.01). The cross-sectional area of all muscle fibre types was increased by training (main effect of training, P < 0.01). Particularly, the cross-sectional area of MHC IIa in the OVX+E-CT group was significantly larger than that in the Sham-CT and OVX-CT groups. Satellite cell numbers were increased in all training groups (main effect of training, P < 0.05), and the myonuclear number was increased by training (main effect of training, P < 0.01), but there was no main group effect. The myonuclear domain size of all muscle fibre types and MHC IIa was increased in all training groups (main effect of training, P < 0.01) and showed a main group effect (P < 0.01). The myonuclear domain sizes of all muscle fibre types and MHC IIa in the OVX+E-CT group were significantly larger than those in the Sham-CT and OVX-CT groups. The total RNA contents revealed main effects of training and the group (P < 0.01); the OVX+E-CT group showed the highest contents (main effect of group, P < 0.01). The mRNA and protein levels of rpS6 were increased in the OVX+E-Sed and CT groups (main effects of group, P < 0.05). Particularly, the 28S ribosomal RNA content in OVX+E-Sed group was significantly higher than that in the OVX-Sed group. CONCLUSIONS: Oestrogen enhanced the resistance training-induced increase in myonuclear domain size but did not affect satellite cells and ribosome biogenesis.

Loquat Leaf Extract Enhances Muscle Contraction-Induced Activation of Protein Synthesis Signaling in Rat Skeletal Muscle.

Loquat (Eriobotrya japonica (Thunb.) Lindl.) leaves are traditionally used to improve muscle weakness, but their effects on muscle protein synthesis require further research. Therefore, we aimed to investigate whether loquat leaf extract (LLE) enhances muscle contraction-induced activation of muscle protein synthesis signaling. Male Wistar rats (12 weeks old, n = 6/group) were categorized into water treatment (CON) and LLE treatment (LLE) groups. The rats were administered distilled water or LLE (1.5 g/kg/day) once a day by oral gavage for 7 days. On day 7, at 3 h post-LLE administration, the gastrocnemius muscle in the right leg of each rat was stimulated by electrical muscle stimulation (EMS) (100 Hz, 30 V) through five sets of 10 isometric contractions (7 s contraction, 3 s rest) with 3 min interset intervals. The rats were then sacrificed, and the gastrocnemius muscles of both legs were excised at 3 h post-EMS. The phosphorylation levels of mammalian target of rapamycin complex 1 (mTORC1) signaling pathway molecules (Akt, mTOR, and p70S6K) were determined by Western blotting. Regarding the muscle contraction-induced protein synthesis signaling pathway, Akt phosphorylation at Ser473 was not significantly different between the CON and LLE groups. mTOR phosphorylation at Ser2448 was increased by EMS but did not show a significant difference between the CON and LLE groups. p70S6K phosphorylation at Thr389 was significantly increased in response to EMS, whereas the LLE group showed significantly higher p70S6K phosphorylation at Thr389 than that in the CON group. This suggests that LLE enhances muscle contraction-induced activation of p70S6K phosphorylation in rat skeletal muscles.

Integrative Taxonomy Reveals a New Species of the Genus Lejeunea (Marchantiophya: Lejeuneaceae) from Peninsular Malaysia.

Prior to the advent of molecular work, the observable variation in vegetative reproduction has been used to classify Lejeunea into subgenera and sections. Thereby, the ability of developing caducous leaves was regarded as major factor. A reexamination of several Lejeunea specimens revealed that L. cocoes with caducous leaves shows considerable morphological differences with non-caducous leaved plants of L. cocoes. Phylogenetic analyses based on a three-marker dataset (rbcL, trnLF and the nuclear ribosomal ITS region) indicated two independent and robust lineages of the morpho-species L. cocoes. We consider both clades as two distinct species and therefore describe the new species, L. malaysiana for L. cocoes morpho-species with caducous leaves. Lejeunea malaysiana is characterized by its caducous leaves with ribbon-like and plantlet regenerants, strongly reduced leaf lobules, distant and deeply bilobed underleaves, long-keeled obovoid perianth, and autoicy and ranges from tropical Asia to the Pacific region.

Effect of freeze-thaw cycles on the physicochemical properties, water-holding status, and nutritional values of broiler chicken drumstick.

This study aimed to determine the effects of multiple freeze-thaw (FT) cycles (0, 1, 2, and 4) on the physicochemical properties, water-holding status, and nutritional values of broiler drumsticks. The results showed that L* (lightness) and b* (yellowness) values, thiobarbituric acid-reactive substances, total volatile basic nitrogen, and total viable counts significantly increased but pH values, protein solubility, and sensorial acceptance decreased after four FT cycles (P Ë‚ 0.05). The decreases in moisture content thawing loss, centrifugation loss, drip loss, and cooking loss indicated that the water-holding capacities of samples subjected to multiple FT cycles were diminished. Results of cell microstructure analysis and sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed the occurrence of ruptured muscle cells with decreased fiber diameters and changes in myosin heavy chain band intensity after multiple FT cycles (P Ë‚ 0.05). As the number of FT cycles increased, the content of total free amino acids and polyunsaturated fatty acids including linoleic (C18:2), linolenic (C18:3), eicosatetraenoic (EPA, C20:5), and docosahexaenoic (DHA, C22:6) acids decreased (P Ë‚ 0.05). In conclusion, four repeated FT cycles accelerated the deterioration of physiochemical properties, reduced the water-holding status, and considerably impaired sensory characteristics and nutritional values of chicken meat.

Renal replacement therapy and concurrent fluconazole therapy increase linezolid-related thrombocytopenia among adult patients.

Linezolid has been reported to be associated with thrombocytopenia. However, limited information is available on susceptibility to thrombocytopenia after linezolid usage. We aimed to investigate the risk factors for linezolid-associated thrombocytopenia (LAT). We conducted a retrospective cohort study of patients aged ≥ 18 years who received linezolid for ≥ 5 d during hospitalization in 2019. Information was extracted from electronic medical records. Thrombocytopenia was defined as a platelet count of < 100 × 109/L or a reduction from baseline ≥ 25%. Binary logistic regression and survival analyses were used to evaluate the risk factors for LAT. A total of 98 patients were enrolled. Thrombocytopenia occurred in 53.1% patients, with a median of 9 d after initiation of linezolid. There was no significant difference in the mortality or proportion of platelet transfusions between patients with and without thrombocytopenia. A higher risk of LAT was found in patients who received renal replacement therapy (RRT) (OR 4.8 [1.4-16.4]), or concurrent fluconazole (OR 3.5 [1.2-9.8]). Patients who received RRT (8 vs. 15 d) or concurrent fluconazole (11 vs. 15 d) had a shorter median time to develop thrombocytopenia. Those who simultaneously received RRT and fluconazole had the shortest median of time (6.5 d) and the highest risk of developing thrombocytopenia (87.5%).

Effects of Stepwise Temperature Shifts in Anaerobic Digestion for Treating Municipal Wastewater Sludge: A Genomic Study.

In wastewater treatment plants (WWTP), anaerobic digester (AD) units are commonly operated under mesophilic and thermophilic conditions. In some cases, during the dry season, maintaining a stable temperature in the digester requires additional power to operate a conditioning system. Without proper conditioning systems, methanogens are vulnerable to temperature shifts. This study investigated the effects of temperature shifts on CH4 gas production and microbial diversity during anaerobic digestion of anaerobic sewage sludge using a metagenomic approach. The research was conducted in lab-scale AD under stepwise upshifted temperature from 42 to 48 °C. The results showed that significant methanogen population reduction during the temperature shift affected the CH4 production. With 70 days of incubation each, CH4 production decreased from 4.55 L·g-1-chemical oxygen demand (COD) at 42 °C with methanogen/total population (M·TP-1) ratio of 0.041 to 1.52 L·g-1 COD (M·TP-1 ratio 0.027) and then to 0.94 L·g-1 COD ( M·TP-1 ratio 0.026) after the temperature was shifted to 45 °C and 48 °C, respectively. Methanosaeta was the most prevalent methanogen during the thermal change. This finding suggests that the Methanosaeta genus was a thermotolerant archaea. Anaerobaculum, Fervidobacterium, and Tepidanaerobacter were bacterial genera and grew well in shifted-up temperatures, implying heat-resistant characteristics.

Influence of Particle Size and Zeta Potential in Treating Highly Coloured Old Landfill Leachate by Tin Tetrachloride and Rubber Seed.

Old leachate normally has a low organic compound content, poor biodegradability and is hard to biologically treat. The efficacy of tetravalent metal salts as a coagulant and the application of a natural coagulant as a flocculant in landfill leachate treatment is still inconclusive. Hence, this study aimed to evaluate the potential application of tin tetrachloride (SnCl4) as the main coagulant and the rubber seed (Hevea brasiliensis) (RS) as the natural coagulant aid as the sole treatment in eradicating highly coloured and turbid stabilised landfill leachate present at one of the old local landfills in Malaysia. The standard jar test conducted revealed that SnCl4 was able to eliminate 99% and 97.3% of suspended solids (SS) and colour, respectively, at pH8, with 10,000 mg/L dosages, an average particle size of 2419 d·nm, and a zeta potential (ZP) of -0.4 mV. However, RS was found to be ineffective as the main coagulant and could only remove 46.7% of SS and 76.5% of colour at pH3 with 6000 mg/L dosages, and also exhibited smaller particles (933 d·nm) with ZP values of -6.3 mV. When used as a coagulant aid, the polymer bridging mechanism in RS helped in reducing the SnCl4 concentration from 10,000 mg/L to 8000 mg/L by maintaining the same performances. The presence of 1000 mg/L RS as a coagulant aid was able to remove 100% of SS and 97.6% of colour. The study concluded that RS has the potential to be used together with SnCl4 in treating concentrated leachate with SS and colour.

Heavy Metals in Harvested Rainwater Used for Domestic Purposes in Rural Areas: Yatta Area, Palestine as a Case Study.

Rainwater harvesting is considered one of the most important water resources in the Palestinian countryside. In this research, the study area chosen for the study was Yatta town in Hebron city. 75 water samples were collected from 74 cisterns in a number of neighborhoods in Yatta, and a structured household survey was conducted with the same households where the water samples were collected. Statistical analysis was made using the SPSS software. An analysis for the samples was made using ICP-MS to test the existence of a number of heavy metals, namely Pb, Cr, Mn, Co, Ni, Cu, Zn and Cd. The results were compared with the WHO and Palestinian limits for drinking water quality. Considering the metals Mn, Co, Cu and Cd, neither of the samples exceeded any of the two limits. For the metals, Pb, Cr, and Ni, two samples exceeded both limits. For the metal, Zn, one sample exceeded the WHO limit only. Sources of pollution by heavy metals of the harvested rainwater were identified by means of a questionnaire distributed to the households. The results showed that except for nickel and the water collection surface of the cistern factor, there is no direct relationship between the factors and activities that may contribute to contaminate harvested rainwater with heavy metals and the existence of heavy metals beyond local and international limits. Based on the questionnaire and literature: Possible sources of lead and zinc are the roof, storage tanks, distribution systems and plumbing; possible sources of chromium are road dust, asbestos brakes and anthropogenic activities occurring around the house; possible source of nickel is leaching from metals in contact with harvested rainwater such as pipes and fittings which are used to collect the harvested rainwater. In addition, an assessment of the potential health risks due to contamination of the harvested rainwater by heavy metals was made for all the samples that exceeded either WHO limit or the Palestinian limit or both. The Chronic Daily Intake (CDI) and the Health Risk Index (HRI) were calculated. The assessment was made for both adults and children. The results showed that all the samples are considered safe (HRI < 1), which means that there are no potential health risks for consumers.

Willingness to Pay for Food Labelling Schemes in Vietnam: A Choice Experiment on Water Spinach.

The growing concern for food safety and quality motivates governments and private sectors to improve consumers' confidence in food systems, such as through adopting certifications and traceability systems. The recent emergence of diverse food labelling schemes and the turbulence in food systems in emerging countries have sparked questions about consumers' valuation of such labels. Nonetheless, little is known on how the familiarity with, trust in and knowledge of these food labelling schemes affect consumers' willingness to pay for labelling schemes in emerging market contexts. This study aims to address these literature gaps by investigating consumers' valuation of existing certifications, branding and traceability labelling schemes in Vietnam. A face-to-face survey was conducted, including a discrete choice experiment on water spinach in Ho Chi Minh City, Vietnam. The findings indicated that Vietnamese consumers are generally willing to pay price premia for food labelling schemes, such as VietGAP certification, EU and USDA organic certifications, private branding and traceable Quick Response (QR) coding. While familiarity and understanding had no significant impact on Vietnamese consumers' valuation, trust was found to be a critical factor shaping willingness to pay for products bearing VietGAP label. Policy implications and marketing strategies for organic certifications and traceability schemes in Vietnam are discussed.