People of discernment should contemplate on the fact that, from the microcosm to the macrocosm, there is a highly systematic process of cleaning and recycling despite continuous movements and mind-boggling circulations. Numerous beings, from huge stars to single-celled bacteria or from vultures to white blood cells, are employed as cleaners.

In the 21st century, as humans we have contaminated the lands, seas, and even outer space, and, so far, we have recycled only 9 percent of the plastics we have produced [1]. It is estimated that the plastic waste in dump sites would reach 35,000 times the weight of the Empire State Building by 2050 [2]. Humankind is incapable of properly performing our cleaning and recycling duties despite all our knowledge, skills, and technology. In comparison, the Earth was in a clean and orderly state before the human intervention has reached its current level.

Cosmic cleanliness and the role of Jupiter

This process of cleaning and purifying occurs all across the universe as stars go through various stages during the lifetime designated for them. Asteroids are swept by planets and placed into certain orbits, and even light cannot escape from a black hole’s gravity. A seven-year study by 100 astronomers and published in 2016 found that stars facilitated the cleaning of the universe by collecting star dust [3]. In a sense, stars work like huge vacuum cleaners to absorb cosmic particles, ensuring that galaxies are cleaner.

Scientists note that Jupiter, 1,321 times larger in volume and 318 times heavier in mass than the Earth, has the duty of acting as a shield to protect our planet from asteroids [4]. If asteroids with a diameter up to 10 meters escape the giant planet’s gravitational field, they are eaten up by the Earth’s atmosphere through friction. NASA reports that there is no record of any person killed by an asteroid, and the likelihood of a big asteroid hitting the Earth for the next several centuries is calculated as extremely low [5]. The creation of suitable conditions for the life on Earth is strongly connected to the size and location of Jupiter.

Self-cleaning of the atmosphere and skies washed by rainfall

Air pollution is a very thought-provoking example of how human beings mismanage available resources with their proclivity for interfering with everything. A 2011 study revealed that the atmosphere is much more capable of self-cleaning than previously thought [6]. It was found that air pollution declined due to quarantine measures implemented during the recent COVID-19 pandemic. Thus, the nitrogen dioxide levels decreased by 30 percent in the United States, and 49 percent in Rome, making stars more visible to the naked eye [7].

When water evaporates, it leaves sediments behind, and water vapor is stored in clouds that are capable of holding tons of water. When needed, this vapor turns back into water and falls down on the earth in the form of rainfall that also clears away the dust particles hanging on the air. This is another process of purification. Having cleaned the air, the water is then filtered through different layers of soil, becoming purer, and it is eventually made available as groundwater that can be safely consumed by human beings.

Water as universal solvent

What sets water apart from other liquids, in addition to its numerous miraculous characteristics, is that many substances can easily dissolve in water. As such, water is referred to as a universal solvent, in scientific parlance. Water molecules are formed with positively charged hydrogen ions (H⁺) bonded to negatively charged hydroxide ions (OH^–); they have a polar chemical structure. This allows water to be pulled by different molecules. Thus, chemical substance such as minerals and food molecules attached to water molecules are carried away with water [8], and in this way, water acts both as a cleaning and shipping agent. Water ensures the dissolution of the molecules required for our bodies. Working in perfect harmony with our kidneys, it also fulfills the duty of transporting waste materials produced as a result of metabolic activities to excretion organs and discharging them out of the body.

Bacteria: heroes of recycling

The fungi feeding on radiation at the Chernobyl Nuclear Power Plant, the worms collecting poisonous heavy metals, and the bacteria decomposing the oil leaking into the sea are some of the examples of nature’s janitors. Bacteria, in particular, are the heroes of recycling on Earth. In carbon, nitrogen, sulfur, and phosphor cycles, bacteria ensure that these elements are turned into forms that can be easily used by plants and animals. In performing their duty of filtering and refining, bacteria break up dead organisms, giving nitrogen to the soil in the form of ammonia and to the atmosphere through denitrification [9].

Bacteria, making up more than three-fourths of the known species, have been performing this duty of decomposing and recycling perfectly for millions of years. “If it were not for this cleaning, sweeping and careful tending, in one year a hundred thousand animal species would have been choked on the face of the earth,” Bediuzzaman Said Nursi notes [10]. For instance, the number of eggs laid by the progeny of a single housefly in five months exceeds five trillion. In other words, the progeny of a housefly weighing about 1 percent of 1 gram can produce an army of houseflies weighing 80,000 tons [11]. If only dead bodies of houseflies were not cleaned, it would be impossible to live on Earth.

Vultures as cleaners

Vultures are another group of animals that fulfill the duty of cleaning. It was calculated that a single vulture provides waste removal services worth about $11,600 during its lifetime. As the number of vultures declined in Asia, the population of wild dogs increased by 5.5 million, and cases of rabies skyrocketed; some 47,000 people died [12].

Cleaning factories in our bodies

The human body, too, features a never-ceasing process of cleaning, purification, and repair. Every breath we take, or every pulse of our heart, is part of this biological and chemical cleaning process. White blood cells go after bacteria and purify the blood like a predator stalking its prey [13]. Our tears contain antimicrobial molecules that can directly kill several pathogenic organisms [14]. Macrophages patrolling under our skin are like garbage trucks that collect damaged cells and bacteria [15].

All these systems and many similar ones in our bodies are astonishing manifestations of infinite wisdom and consciousness. Freeing the mind from doubts or polishing the heart with the light of belief are among spiritual manifestations of this principle of cleanliness in humans.

“The universe is a vast, constantly working factory and the globe of the earth a hostel and guesthouse which is continually filled and emptied. Generally, factories, hostels and guesthouses which are thus used become much dirtied and soiled with filth, debris and rubbish, and putrid matter accumulates in all parts of them. They cannot be occupied unless they are kept with care and cleaned and swept; human beings are overwhelmed by the dirt. The factory of the universe and guesthouse of the earth, however, are totally pure, clean and spotless, and completely unsoiled, untainted and fresh; there is nothing unnecessary, nothing without benefit, not a random piece of dirt to be found. Even if there is apparently, it is quickly thrown into a transformation machine and cleaned“[16].

References

1. European Space Agency (ESA), 2017, “Dealing with space debris”, youtu.be/eYVsVRgiS0w
2. Laura Parker, “Here is how much plastic trash is littering the Earth”, National Geographic, 2018, www.nationalgeographic.com/science/article/plastic-produced-recycling-waste-ocean-trash-debris-environment
3. Sky News, “Stars Hoover Up Cosmic Dust To Clean Universe”, 2016, news.sky.com/story/stars-hoover-up-cosmic-dust-to-clean-universe-10333797
4. “NASA’s Mission Juno. Why study Jupiter?” www.missionjuno.swri.edu/origin?show=hs_origin_story_jupiters-influence
5. “The Probability of Collisions with Earth”, www2.jpl.nasa.gov/sl9/back2.html
6. “Atmosphere’s self-cleaning capacity surprisingly stable.” ScienceDaily, National Oceanic and Atmospheric Administration, www.sciencedaily.com/releases/2011/01/110106145434.htm
7. S. Borenstein, “As People Stay Home, Earth Turns Wilder and Cleaner”, APNews, 2020. apnews.com/article/environment-ma-state-wire-united-states-il-state-wire-az-state-wire-726ff63bb43bdca65e41625b1e223040

8. “Water,” https://en.wikipedia.org/wiki/Water
9. “Bacterial World”, Museum of Natural History, University of Oxford, 2018, www.oum.ox.ac.uk/bacterialworld/
10. Bediüzzaman Said Nursi, Flashes, 30th Flash, trans. Şükran Vahide, Istanbul: Sözler Neşriyat A.Ş., 2009.
11. “Housefly,” https://en.wikipedia.org/wiki/Housefly.
12. J. Law, “Why We Need Birds (far more than they need us)”, 2019, www.birdlife.org/news/2019/01/04/why-we-need-birds-far-more-than-they-need-us/
13. David Rogers, “Neutrophil Chasing Staphylococcus Aureus”, Vanderbilt University, www.youtube.com/watch?v=HToFRGVNap8&ab_channel=Cleu
14. A. M. McDermott, “Antimicrobial Compounds in Tears. Experimental eye research,” 2013, 117, 53–61. doi.org/10.1016/j.exer.2013.07.014
15. Kimberly Repp. “Ouch – Body Defense and Repair”. ASU – Ask A Biologist. 21 February, 2015. https://askabiologist.asu.edu/explore/when-body-attacked
16. Nursi, ibid.

No link found between gender and performance in physics courses

Dew et al. Gendered performance differences in introductory physics: A study from a large land-grant university. Physical Review Physics Education Research, February 2021.

A new study discredits the stereotype that male students perform better than female students in science, more specifically in physics. Researchers from Texas A&M University analyzed the grades of more than 10,000 students enrolled in four introductory physics courses over a decade-long period and found no evidence that male students consistently outperformed female students in these courses. Their analyses showed that exam success and final grades were largely independent of student gender. In addition to multiple statistical analyses of course-level data, researchers distributed questionnaires to students to see how the results aligned with student perceptions. Interestingly, student responses showed that female students had lower perceptions of their performance than their male classmates. The only class where female students perceived their performance as equal to their male classmates was algebra-based mechanics, in which females outperformed males. This study can be another step in breaking up the preconceived notion of a societal bias based on gender in physics. Moreover, it may help to fight against gender stereotypes that negatively impact so many female students and harm women in STEM (science, technology, engineering, and math) related courses.  All students should have equal opportunities and chances for success.

Air pollution may cause chronic heart disease in children

Prunicki et al. Air pollution exposure is linked with methylation of immunoregulatory genes, altered immune cell profiles, and increased blood pressure in children. Scientific Reports, February 2021.

Exposure to air pollution has been linked to various diseases in adults, but no study had yet extensively investigated its long-term impacts on children. A new study suggests that children exposed to air pollution, such as wildfire smoke and car exhaust, for as little as one day may become more prone to heart disease in adulthood. Researchers investigated air pollution’s effects at the single-cell level in a group of 221 school-aged children (6–8 years). They focused on Fresno, California, a city with some of the country’s highest air pollution levels due to industrial agriculture and wildfires. Using a combination of continuous daily pollutant concentrations measured at central air monitoring stations in Fresno, daily concentrations from periodic spatial sampling, and meteorological and geophysical data, the research team estimated average air pollution exposures for 1 day, 1 week, and 1, 3, 6, and 12 months prior to each participant visit. When combined with health and demographics questionnaires, blood pressure readings, and blood samples, the data showed that polluted air can alter gene regulation in cardiovascular and immune systems of children in a way that can impact long-term health. In particular, exposure to fine particles, carbon monoxide, and ozone over time is linked to increased DNA methylation, a form of epigenetic alteration of DNA molecules that can change their activity without changing their sequence. This inheritable change in gene expression may be passed down to future generations. Researchers also found that air pollution exposure leads to an increase in monocytes, white blood cells that play a key role in the buildup of plaques in arteries and could possibly predispose children to heart disease in adulthood. According to the World Health Organization, air pollution is one of the leading causes of death in children. Children typically breath faster than adults, making them more susceptible to health problems by rapidly inhaling low quality air. With air quality deteriorating globally, we all need to be more careful and conscientious to protect kids from air pollution.

Sleep memories

Clawson et al. Causal role for sleep-dependent reactivation of learning-activated sensory ensembles for fear memory consolidation. Nature Communications, February 2021.

Sleep is very critical for brain functions. Inadequate sleep can impair our abilities to concentrate, think clearly, and process memories. Past studies showed that regions of the brain that are highly active during intensive learning surprisingly show more activity during sleep. However, which biological purpose this “reactivation” of memories during sleep serves remains unclear. To address this question, researchers studied how memories associated with a specific sensory event are formed and stored in mice. They specifically examined how a fearful memory formed in relation to a particular visual stimulus in the brain. By focusing on a specific set of neurons in the primary visual cortex, researchers were able to create a visual memory test. When they ran this test in various conditions, the mice with regular sleep learned to fear the specific stimuli that had been paired with a foot shock. However, the mice with disrupted sleep had no fear association with the visual stimulus. These sleep-deprived mice seemed to process the fact that they should be afraid, but there may have been a lost connection regarding what they were supposed to be afraid of. These observations suggest that sleep-associated reactivation of the neurons encoding that stimulus is required for them to make an accurate fear association with a visual stimulus. These findings have important implications for anxiety and post-traumatic stress disorders. In the absence of sleep, the brain seems to manage processing the fact that we should experience emotions, but we may be unable to link those emotions to exact causes accurately. That specification process may be one that goes awry with such anxiety-related disorders.