What is the effect of the socio-economic development of European countries, as measured by the HDI, on the mortality rate from hypertensive heart disease within the older population (50+)?

How does the presence of earthworms influence the growth of stem in length [cm] of monocots (Avena sativa) and dicots (Phaseolus vulgaris) as measured by the mean height of the stem through 25 days?

How do altering salicylic acid concentrations (0.0%, 0.5%, 1.0%, 1.5%, 2.0%) affect the germination of Capsicum annuum longum seeds measuring the radicle length (mm) of the sprouts over 7 days?

How does the variety of Capsicum annuum L. (green bell pepper, yellow bell pepper, red bell pepper, red sweet long pepper) and Allium cepa L. (yellow onion, red onion, white onion) influence their vitamin C content in mg/100g, as measured by vegetable juice volume needed to titrate 2 ml of 0.1% DCPIP solution?

What is the effect of increasing iron (III) chloride concentration (0 mg/L, 2mg/L, 4mg/L, 6mg/L, 8mg/L, 10mg/L) on the growth of duckweed (Lemna minor) in terms of change in number of leaves over 5 days?

What is the effect of the concentration (0%, 20%, 40%, 60%, 80%, 100%) of tea tree (Melaleuca alternifolia) oil on the growth of bacteria (non-pathogenic DH5- Alpha Escherichia coli) measured in the diameter of the inhibition zone around the paper disc?

How does the concentration of 50ml of ethanol solution (15%, 30%, 45%, 60%, 75%) influence the cell membrane permeability of beetroot, measured by the absorption transmission of light (Au) using a colorimeter, for 10 minutes?

The effect of sodium bicarbonate on pepsin enzyme activity

To what extent do different herbal teas (peppermint, ginger, lemongrass, turmeric, and chamomile) affect the activity of α-amylase enzyme, measured using a spectrophotometer (± 0.001A.U) to record the wavelength absorbance at 430nm after the addition of iodine to the solution?

What effect do different organic acids (Lactic acid, Citric acid, Ascorbic acid (Vitamin C)) and varying their respective concentrations (2%, 5%, 10%) have on the growth of Escherichia coli (E.coli) bacteria, as measured by measuring the Zone of Inhibition (ZOI) formed after 24 hours of incubation?

How does the concentration of Punica granatum (pomegranate) extract, in terms of the percentage volume-by-volume ratio of pomegranate juice to water, affect the digestion of starch by the enzyme amylase, as measured by UV-visible spectrophotometry while keeping the weight-by-volume concentration of starch (1%), weight-by-volume concentration of amylase (0.5%) and incubation temperature (35 ̊C) constant?

How does priming of Vigna unguiculata (black-eyed peas) seeds with different concentrations of ascorbic acid (0mg/dm3, 10mg/dm3, 20mg/dm3, 30mg/dm3, 40mg/dm3, 50mg/dm3) affect its rate of germination in a 2% salt solution, measured after 5 days while keeping the amount of water added and humidity constant?

What is the effect of using different solutions of raw honey concentrations (0%, 20%, 40%, 60%, 80%, 100%) on the growth of Escherichia coli (E. coli) using the agar well diffusion method, determined by measuring the diameter of the zone of inhibition (mm) after a 24-hour incubation period at 30°C, using a vernier caliper (±0.05mm)?

What is the effect of five different concentrations (0%, 1%, 2%, 3%, 4%) of salt (NaCl) on the on the rate of fermentation of organic green cabbage (brassica oleracea) measured using a pH meter over a period of 6 days?

How does the percentage of sulfuric acid (%) affect the growth of Vigna radiata for 10 days, measured by percentage change in dry mass (%)?

What are the effects of a brief 45 minute exposure to varying temperatures (21.0°C, 25.0°C, 35.0°C, 45.0°C, 55.0°C, 65.0°C, 75.0°C) on the growth of Rhizopus stolonifer pin mold on white bread?

What is the effect of pH (5, 6, 7, 8, and 9) on the rate of activity of amylase, as measured by the time taken for amylase to digest starch?

What is the effect of two wavelengths of light (450 nm, 700 nm) and their light intensities (420 - 620 lux) on the phototropic response of a week-old seedling of Pisum sativum, measured by the angle it bends (degrees) for a period of 4 consecutive days?

How do various soy milk concentrations, ranging from 0% to 100%, affect the hydrolysis rate of protein as measured by change in absorbance levels over time (nm*min-1) over 20 minutes, whilst exposed to the enzyme trypsin?

What is the effect of varying caffeine concentration (0%, 5%, 10%, 15%, 20%, 25%) on the inhibition of lipase enzyme activity on triglycerides in milk, as measured by a stopwatch to record the time (seconds) for the solution to change color caused by a 1% phenolphthalein indicator at room temperature (25ºC)?

How do the different colors of light green, blue, red, and white affect the height increase, measured from soil to the highest point (cm) in Phaseolus vulgaris seedlings during 6 days?

How do household cleaning products (dish soap, toilet cleaner, window cleaner and laundry detergent) diluted with water affect the growth of phaseolus vulgaris beans in cm (from their longest root to the end of the shoot)?

How does temperature(-11.9 °C, 7.7 °C, 14.9 °C, 27.8 °C ) and airflow affect the ripening of the Cavendish, Apple, and Green species of bananas over seven days by measuring the mass (g), brix value (°Bx), and pH of the bananas, while ensuring that days of ripening, acclimatisation period, exposure to air and branch of the banana is standardised and controlled?

What is the effect of the ethanol concentration (20%, 40%, 60%, 80%, 100%) on the rate of osmosis in potatoes through the change in mass (g) of a (2.5x0.5x0.5 cm) potato chip submerged in said ethanol concentration for a 24 hour period?

To what extent does the concentration of sucrose solution (%) affect carbon dioxide production (ppm) during yeast fermentation under 180 seconds?

What is the effect of different concentrations of eucalyptus oil (0%, 20%, 40%, 60%, 80%, 90% and 100%) on the growth of E.coli bacteria, measured by the largest diameter of the zone of inhibition (in cm)?

How does varying sugar content in pure, fresh fruit juices (such as apple, mango, and grape) influence the volume of Carbon Dioxide (ppm) generated during a five-minute fermentation process with Saccharomyces cerevisiae (Baker’s yeast)?

Is there an association between green moss and lichen on the bark of a tree at different heights?

What is the impact of different temperatures (20 ̊C, 25 ̊C, 30 ̊C, 35 ̊C and 40 ̊C) on the rate of fermentation, measured using a gas pressure sensor in kPa/min, in Saccharomyces cerevisiae (yeast)?

How do varying pH levels of water (4, 5, 6, 7, 8) influence the rate of photosynthesis, measured through oxygen output (mg/L ±0.2) over 10 minutes (±0.001s), within Elodea?

How do different pHs of distilled water, H2O, (5.98, 6.90, 7.40, 8.30, 8.70)(±0.02) affect the permeability of cell membranes in cells of Beta vulgaris (beetroot) cells, when temperature is constant at 25.00℃ (±0.05), through examining the quantity of pigment leaked into water using a colorimeter (±1.7%)?

What is the correlation between HDI and the prevalence of HIV (% of population ages 15-49) and how does it vary between a developing (HDI > 0.699) and developed (HDI < 0.699) country in Africa?

How do different concentrations of ethanol [0%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%] affect the catalase activity in potato Solanum Tuberosum measured by the amount of oxygen gas produced after incubating with ethanol for 1 minute and reacting with hydrogen peroxide for 5 minutes?

How do different temperatures (15.0℃, 20.0℃, 25.0℃, 30.0℃, 35.0℃ ± 0.5℃) affect the lactase enzymatic activity in milk determined by the glucose levels (mmol/L) presented after its incubation period (60 minutes) measured using a blood glucose meter?

What is the effect of increasing Fe (III) concentration (2mg/L, 4mg/L, 6mg/L, 8mg/L, 10mg/L) on the growth of Duckweed (Lemna minor) in terms of change in number of leaves over 5 days?

How do varying concentrations of hydrogen peroxide (0%, 1.5%, 3.0%, 4.5%, 6.0%, 7.5%) affect the radicle length (mm) of Vigna radiata during its one-hour imbibition (pre-germinative seed soaking) before seed germination over a time period of 72 hours?

How will differences in soluble fiber concentrations, ranging from 0% to 2%, affect the rate of hydrolysis of starch in 10 minutes, using a pancreatic amylase enzyme?

How does the increase in the mean Body Mass Index (BMI) (24.0 – 30.9 kg/m2 ) for countries have an effect on their case-fatality (%) of patients with SARS-CoV-2, measured using the overall deaths and cases of SARS-CoV-2 patients in the countries, using the databases of World Health Organization, and Johns Hopkins Coronavirus Resource Center?

How do varying concentrations (0.0,0.1,0.2,0.3,0.4,0.5mol/dm3) of sucrose (C12H22O11) affect the cell respiration rate in yeast (Saccharomyces cerevisiae) by measuring the volume of carbon dioxide (CO2) gas released after yeast activation using a gas syringe over a period of 10 minutes?

How does the use of germination stimulators; mineral “Seedboodster Plus” and hummus-based “Brunatne BioZloto” affect germination capacity (GC), germination speed (GS) and mean germination time (MGT) of fresh and old seeds of alfalfa (Medicago sativa)?