Saturday, June 27, 2020

List of popular video game consoles

This post is a list of popular video game consoles. The  are 38 consoles listed below chronologically by release date.

Magnavox Odyssey (1972) - Magnavox
Photo source: Wikimedia CommonsEvan-Amos



Atari 2600 (1977) - Atari



Color TV-Game (1977) - Nintendo
Photo source: Wikimedia CommonsEvan-Amos



Magnavox Odyssey 2 (1978) - Magnavox
Photo source: Wikimedia CommonsEvan-Amos
Photo license: CC BY-SA 3.0



Intellivision (1979) - Mattel Electronics
Photo source: Wikimedia CommonsEvan-Amos
Photo license: CC BY-SA 3.0



ColecoVision (1982) - Coleco Industries
Photo source: Wikimedia CommonsEvan-Amos



Atari 5200 (1982) - Atari



Photo source: Wikimedia CommonsEvan-Amos



SG-1000 (1983) - Sega
Photo source: Wikimedia CommonsEvan-Amos
Photo license: CC BY-SA 3.0



Master System (1985) - Sega
Photo source: Wikimedia CommonsEvan-Amos



Atari 7800 (1986) - Atari
Photo source: Wikimedia CommonsEvan-Amos
Photo license: CC BY-SA 3.0



Sega Genesis (1988) - Sega
Photo source: Wikimedia CommonsEvan-Amos



Game Boy (1989)- Nintendo
Photo source: Wikimedia CommonsEvan-Amos



Photo source: Wikimedia CommonsEvan-Amos



Sega Game Gear (1990) - Sega
Photo source: Wikimedia CommonsEvan-Amos



Neo Geo AES (1990) - SNK
Photo source: Wikimedia CommonsEvan-Amos
Photo license: CC BY-SA 3.0



Atari Jaguar (1993) - Atari
Photo source: Wikimedia CommonsEvan-Amos
Photo license: CC BY-SA 3.0



Neo Geo CD (1994) - SNK
Photo source: Wikimedia CommonsEvan-Amos



Sega Saturn (1994) - Sega
Photo source: Wikimedia CommonsEvan-Amos



Playstation (1994) - Sony
Photo source: Wikimedia CommonsEvan-Amos



Nintendo 64 (1996) - Nintendo
Photo source: Wikimedia CommonsEvan-Amos



Dreamcast (1998) - Sega
Photo license: CC BY-SA 3.0



Game Boy Color (1998) - Nintendo
Photo source: Wikimedia CommonsEvan-Amos



Playstation 2 (2000) - Sony
Photo source: Wikimedia CommonsEvan-Amos



Xbox (2001) - Microsoft
Photo source: Wikimedia CommonsEvan-Amos



Game Boy Advance (2001) - Nintendo



GameCube (2001) - Nintendo



Nintendo DS (2004) - Nintendo

Playstation Portable (2004) - Sony
Photo source: Wikimedia CommonsEvan-Amos



Xbox 360 (2005) - Microsoft
Photo source: Wikimedia CommonsEvan-Amos



Wii (2006) - Nintendo
Photo source: Wikimedia CommonsEvan-Amos



Playstation 3 (2006) - Sony
Photo source: Wikimedia CommonsEvan-Amos



Nintendo 3DS (2011) - Nintendo
Photo source: Wikimedia CommonsEvan-Amos



Playstation Vita (2011) - Sony
Photo source: Wikimedia CommonsEvan-Amos



Wii U (2012) - Nintendo
Photo source: Wikimedia CommonsEvan-Amos



Xbox One (2013) - Microsoft
Photo source: Wikimedia CommonsEvan-Amos



Playstation 4 (2013) - Sony
Photo source: Wikimedia CommonsEvan-Amos



Nintendo Switch (2017) - Nintendo
Photo source: Wikimedia CommonsEvan-Amos

Tuesday, June 23, 2020

List of major neurotransmitters

This post is a list of major neurotransmitters. There are 8 neurotransmitters listed below alphabetically. License: CC BY-SA 3.0

1. Adenosine (stress response)
"In general, adenosine has an inhibitory effect in the central nervous system (CNS). Caffeine's stimulatory effects are credited primarily (although not entirely) to its capacity to block adenosine receptors, thereby reducing the inhibitory tonus of adenosine in the CNS." (Wikipedia: Adenosine, 6.18.21 UTC 01:23)

2. Dopamine (reward, motor control, hormone release)
"The brain includes several distinct dopamine pathways, one of which plays a major role in the motivational component of reward-motivated behavior... Other  brain dopamine pathways are involved in motor control and in controlling  the release of various hormones." (Wikipedia: Dopamine, 8.6.21 UTC 16:56)

3. Endorphins (pain inhibitor)
"The principle function of endorphins is to inhibit the communication of pain signals. Endorphins may also produce a feeling of euphoria..." (Wikipedia: Endorphins, 7.23.21 UTC 14:34)

4. GABA (inhibitor)
"Gamma-Aminobutyric acid or GABA is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system." (Wikipedia: GABA, 7.6.21 UTC 16:21)

5. Glutamate (excitation)
"[Glutamate] is used by every major excitatory function in the vertebrate brain, accounting in total for well over 90% of the synaptic connections in the human brain." (Wikipedia: Glutamate, 7.7.21 UTC 01:24)

6. Oxytocin (social bonding)
"[Oxytocin] is normally produced in the hypothalamus and released by the posterior pituitary. It plays a role in social bonding sexual reproduction, childbirth, and the period after childbirth." (Wikipedia: Oxytocin, 10.26.22 UTC 18:03)

7. Noradrenaline (stress response)
"The general function of norepinephrine is to mobilize the brain and body for action. Norepinephrine release is lowest during sleep, rises during wakefulness, and reaches much higher levels during situations of stress or danger, in the so-called fight or flight response." (Wikipedia: Norepinephrine, 10.31.22 UTC 02:57)

8. Serotonin (happiness, cognition, reward, learning, memory)
"[Serotonin's] biological function is complex and multifaceted, modulating cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vasoconstriction." (Wikipedia: Serotonin, 9.17.22 UTC 07:54)

List of human brain systems

This post is a list of major systems in the human brain. There are 11 systems listed below alphabetically. License: CC BY-SA 3.0

1. Auditory system (hearing)
"The auditory system is the sensory system for the sense of hearing. It includes both the sensory organs (the ears) and the auditory parts of the sensory system." (Wikipedia: Auditory system, 7.6.21 UTC 03:58)

2. Central nervous system (brain and spinal cord)
"The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because it integrates the received information and coordinates and influences the activity of all parts of the bodies of bilaterally symmetric animals..." (Wikipedia: Central nervous system, 8.9.21 UT  07:04)

3. Endocrine system (hormones)
"The endocrine system is a messenger system comprising feedback loops of the hormones release by internal glands of an organism directly into the circulatory system, regulating distant target organs." (Wikipedia: Endocrine system, 7.30.21 UTC 17:33)

4. Gustatory system (taste)
"The gustatory system or sense of taste is the sensory system that is partially responsible for the perception of taste (flavor)." (Wikipedia: Taste, 8.2.21 UTC 05:20)

5. Limbic system (emotion, behavior, motivation, memory, smell)
"[The limbic system] supports a variety of functions including emotion, behavior, motivation, long-term memory and olfaction. Emotional life is largely housed in the limbic system." (Wikipedia: Limbic system, 8.3.21 UTC 09:03)

6. Olfactory system (smell)
"The olfactory system, or sense of smell, is the sensory system used for smelling (olfaction)." (Wikipedia: Olfactory system, 8.3.21 UTC 00:32)

7. Peripheral nervous system (nerves outside brain and spinal cord)
"The peripheral nervous system consists of the nerves and ganglia outside the brain and the spinal cord. The main function of the PNS is to connect the CNS to the limbs and organs, essentially serving as a relay between the rain and spinal cord and the rest of the body." (Wikipedia: Peripheral nervous system, 7.19.21 UTC 11:57)

8. Reward system (motivation)
"The reward system is a group of neural structures responsible for incentive salience (i.e. motivation and 'wanting', desire, or craving for a reward), associative learning (primarily positive reinforcement and classical conditioning), and positively-valenced emotions, particularly ones which involve pleasure as a core component." (Wikipedia: Reward System, 8.14.21 UTC 07:28)

9. Somatosensory system (touch)
"Somatic senses... include the sense of touch, proprioception (sense of position and movement), and (depending on usage) haptic perception." (Wikipedia: Somatosensory system, 6.3.21 UTC 13:18)

10. Ventricular system (cerebrospinal fluid)
"The ventricles are filled with cerebrospinal fluid (CSF) which bathes and cushions the brain and spinal cord within their bony confines." (Wikipedia: Ventricular system, 5.6.21 UTC 13:13)

11. Visual system (vision)
"The visual system comprises the sensory organ (the eye) and the part of the central nervous system which gives organisms the ability to process visual detail as sight, as well as enabling the formation of several non-image photo response functions." (Wikipedia: Visual system, 8.10.21 UTC 09:10)

Sunday, June 21, 2020

List of human brain regions

This post is a list of major human brain regions. There are 25 regions listed below alphabetically. License: CC BY-SA 3.0

1. Amygdalae - (fear and anger)
"Shown to perform a primary role in the processing of memory, decision making and emotional responses (including fear, anxiety and aggression), the amygdalae are considered part of the limbic system." (Wikipedia: Amygdala, 8.4.21 UTC 02:14)

2. Cerebellum - (coordination)
"The human cerebellum does not initiate movement, but contributes to coordination, precision and accurate timing: it received input from sensory systems of the spinal cord and from other parts of the brain, and integrates these inputs to fine-tune motor activity." (Wikipedia: Cerebellum, 6.18.21 UTC 06:13)

3. Claustrum - (consciousness)
"The claustrum has been shown to have widespread activity to numerous cortical components, all of which have been associated with having components of consciousness and sustained attention." (Wikipedia: Claustrum, 7.25.21 UTC 05:34)

4. Corpus Callosum - (connects left and right sides)
"The corpus callosum... is a wide, thick nerve tract, consisting of a flat bundle of commissural fibers beneath the cerebral cortex in the brain... It spans part of the longitudinal fissure, connecting the left and right cerebral hemispheres, enabling communication between them." (Wikipedia: Corpus callosum, 7.30.21 UTC 15:33)

5. Fornix - (output of hippocampus)
"The fornix is a C-shaped bundle of nerve fibers in the brain that acts as the major output tract of the hippocampus." (Wikipedia: Fornix, 8.10.21 UTC 18:22)

6. Frontal lobe (cerebrum) - (decision-making)
"The entirety of the frontal cortex can be considered the 'action cortex', much as the posterior cortex is considered the 'sensory cortex'. It is devoted to action of one kind or another: skeletal movement, ocular movement, speech control and the expression of emotions." (Wikipedia: Frontal lobe, 8.2.21 UTC 19:00)

7. Globus pallidus - (subconscious movement)
"The globus pallidus is a structure in the brain involved in the regulation of voluntary movement. It is part of the basal ganglia, which, among many other things, regulate movements that occur on the subconscious level." (Wikipedia: Globus pallidus, 10.25.20 UTC 19:20)

8. Hippocampus - (memory)
"The hippocampus is part of the limbic system, and plays important roles in the consolidation of information from short-term memory to long term memory, and in spatial memory that enables navigation." (Wikipedia: Hippocampus, 7.5.20 UTC 06:09)

9. Hypothalamus - (hormone regulation)
"The hypothalamus is responsible for the regulation of certain metabolic processes and other activities of the autonomic nervous system. It synthesizes and secretes certain neurohormones, called releasing hormones or hypothalamic hormones, and these in turn stimulate or inhibit the secretion of hormones from the pituitary gland." (Wikipedia: Hypothalamus, 8.12.21 UTC 04:33)

10. Medulla oblongata - (breathing, heart rate, blood pressure, sleep)
"The medulla contains the cardiac, respiratory, vomiting and vasomotor centers and therefore deals with the autonomic functions of breathing, heart rate and blood pressure as well as the sleep wake cycle." (Wikipedia: Medulla oblongata, 4.8.21 UTC 20:42)

11. Midbrain - (vision, hearing, coordination, sleep, temperature)
"The midbrain... is associated with vision, hearing, motor control, sleep and wakefulness, arousal (alertness), and temperature regulation." (Wikipedia: Midbrain, 6.22.21 UTC 00:52)

12. Nucleus Accumbens - (reward)
"As a whole, the nucleus accumbens has a significant role in the cognitive processing of motivation aversion, reward (i.e. incentive salience, pleasure, and positive reinforcement) and reinforcement learning (e.g. Pavlovian-instrument transfer); hence, it has a significant role in addiction. " (Wikipedia: Nucleus accumbens, 8.9.20 UTC 21:19)

13. Occipital lobe (cerebrum) - (vision)
"The occipital lobe is the visual processing center of the mammalian brain... The occipital lobe is divided into several functional visual areas. Each visual area contains a full map of the visual world." (Wikipedia: Occipital lobe, 7.22.21 UTC 20:21)

14. Olfactory bulb - (smell)
"It sends olfactory information [smell] to be further processed in the amygdala, the orbitofrontal cortex [frontal lobe] and the hippocampus where it plays a role in emotion, memory and learning." (Wikipedia: Olfactory bulb, 7.6.21 UTC 00:38)

15. Optic nerve - (connects eyes to brain)
"The optic nerve... is a paired cranial nerve that transmits visual information from the retina to the brain. In humans, the optic nerve... extends from the optic disc to the optic chiasma nad continues as the optic tract to the lateral geniculate nucleus [thalamus], pretectal nuclei [midbrain], and superior colliculus [midbrain]." (Wikipedia: Optic nerve, 7.14.21 UTC 21:06)

16. Parietal lobe (cerebrum) - (touch, navigation)
"The parietal lobe integrates sensory information among various modalities, including spatial sense and navigation (proprioception), the main sensory receptive area for the sense of touch in the somatosensory cortex... The major sensory inputs from the skin (touch, temperature and pain receptors) relay through the thalamus to the parietal lobe." (Wikipedia: Parietal lobe, 7.5.21 UTC 09:14)

17. Pineal gland - (melatonin and sleep)
"The primary function of the pineal gland is to produce melatonin. Melatonin has various functions in the central nervous system, the most important of which is to help modulate sleep patterns." (Wikipedia: Pineal gland, 8.14.21 UTC 07:32)

18. Pons - (breathing, hearing, taste, touch, eating, facial expression, etc.)
"The functions of [the pons] include regulation of respiration, controls involuntary actions, sensory roles in hearing, equilibrium, and taste, and in facial sensations such as touch and pain, as well as motor roles in eye movement, facial expressions, chewing, swallowing, and the secretion of saliva and tears." (Wikipedia: Pons, 7.10.21 UTC 07:03)

19. Spinal cord - (connects body parts to brain)
"The spinal cord functions primarily in the transmission of nerve signals from the motor cortex to the body, and from the afferent fibers of the sensory neurons tot he sensory cortex. It is also center for coordinating many reflexes and contains reflex arcs that can independently control reflexes." (Wikipedia: Spinal cord, 8.5.21 UTC 04:35)

20. Striatum - (reward, impulsivity)
"The ventral striatum, and the nucleus accumbens in particular, primarily mediates reward, cognition, reinforcement, and motivational salience, whereas  the dorsal striatum primarily mediates cognition involving motor function, certain executive functions (e.g. inhibitory control and impulsivity), and stimulus-response learning..." (Wikipedia: Striatum, 8.6.21 UTC 18:42)

21. Substantia nigra - (eye movement, motor planning, reward)
"The substantia nigra is an important player in brain function, in particular, in eye movement, motor planning, reward-seeking, learning, and addiction. Many of the substantia nigra's effects are mediated through the striatum. The dopaminergic input to the striatum via the nigrostriatal pathway is intimately linked with striatum's function." (Wikipedia: Substantia nigra, 6.5.21 UTC 08:19)

22. Subthalamic nucleus - (motor control)
"The function of the subthalamic nucleus is unknown, but current theories place it as a component of the basal ganglia control system that may perform action selection. It is thought to implement the so-called 'hyperdirect pathway' of motor control, contrasting with the direct and indirect pathways implemented elsewhere in the basal ganglia." (Wikipedia: Subthalamic nucleus, 5.24.21 UTC 01:56)

23. Temporal lobe (cerebrum) - (language, visual memory)
"The temporal lobe is involved in processing sensory input in derived meanings for the appropriate retention of visual memory, language comprehension, and emotion association." (Wikipedia: Temporal lobe, 5.16.21 UTC 03:15)

24. Thalamus - (relay station)
"The thalamus has multiple functions, generally believed to act as a relay station, or hub, relaying information between different subcortical areas and the cerebral cortex. In particular, every sensory system (with the exception of the olfactory system) includes a thalamic nucleus that receives sensory signals and sends them to the associated primary cortical area." (Wikipedia: Thalamus, 7.14.21 UTC 02:24)

25. Ventricular system - (cerebrospinal fluid)
"The ventricular system is a set of four interconnected cavities (ventricles or lumen) in the brain. Within each ventricle is a region of choroid plexus which produces the circulating cerebrospinal fluid (CSF)." (Wikipedia: Ventricular system, 5.6.21 UTC 13:13)

Wednesday, June 17, 2020

List of element groups


Photo source: Wikimedia Commons, Offnfopt

This post is a list of quotes about the element groups. There are 39 quotes and 18 element groups listed below. License: CC BY-SA 3.0

1. Group 1 (alkali metals and hydrogen)


Hydrogen (1). Lithium (3), Sodium (11), Potassium (19), Rubidium (37), Caesium (55), Francium (87)

"All alkali metals have their outermost electron in an s-orbital: this shared electron configuration results in their having very similar characteristic properties." (Wikipedia: Alkali metal, 8.13.21 UTC 00:46)

"The alkali metals are all shiny, soft, highly reactive metals at standard temperature and pressure and readily lose their outermost electron to form cations with charge +1." (Wikipedia: Alkali metal, 8.13.21 UTC 00:46)

"All the alkali metals are highly reactive and are never found in elemental forms in nature." (Wikipedia: Alkali metal, 8.13.21 UTC 00:46)

2. Alkaline earth metals


Helium (2), Beryllium (4), Magnesium (12), Calcium (20), Strontium (38), Barium (56), Radium (88)

"[Alkaline earth metals] have very similar properties: they are all shiny, silvery-white, somewhat reactive metals at standard temperature and pressure." (Wikipedia: Alkaline earth metal, 7.22.21 UTC 18:23)

"Structurally, they (together with helium) have in common an outer s-orbital which is full..." (Wikipedia: Alkaline earth metal, 7.22.21 UTC 18:23)

"The alkaline earth metals react with the halogens to form ionic halides, such as calcium chloride, as well as reacting with oxygen to form oxides such strontium oxide." (Wikipedia: Alkaline earth metal, 7.22.21 UTC 18:23)

3. Scandium group


Scandium (21), Yttrium (39), Lanthanum (57), Lutetium (71), Actinium (89), Lawrencium (103)

"All group 3 elements are rather soft, silvery-white metals, although their hardness increases with atomic number." (Wikipedia: Group 3 element, 7.8.21 UTC 13:07)

"Scandium, yttrium and lutetium have no documented biological role in living organisms." (Wikipedia: Group 3 element, 7.8.21 UTC 13:07)

"Scandium, yttrium, lanthanum, and lutetium tend to occur together with the other lanthanides (except promethium) in the Earth's crust, and are often harder to extract from their ores." (Wikipedia: Group 3 element, 7.8.21 UTC 13:07)

4. Titanium group


Titanium (22), Zirconium (40), Hafnium (72), Rutherfordium (104)

"All the group 4 elements are hard, refractory metals. Their inherent reactivity is completely masked due to the formation of a dense oxide layer that protects them from corrosion..." (Wikipedia: Group 4 element, 6.5.21 UTC 19:57)

"The group 4 elements are not known to be involved in the biological chemistry of any living systems." (Wikipedia: Group 4 element, 6.5.21 UTC 19:57)

"The chemistry of group 4 elements is dominated by the group oxidation state." (Wikipedia: Group 4 element, 6.5.21 UTC 19:57)

5. Vanadium group


Vanadium (23), Niobium (41), Tantalum (73), Dubnium (105)

"The lighter three group 5 elements occur naturally and share similar properties; all three are hard refractory metals under standard conditions." (Wikipedia: Group 5 element, 1.12.21 UTC 06:58)

"All the elements of the group are reactive metals with high melting points." (Wikipedia: Group 5 element, 1.12.21 UTC 06:58)

"Out of the group 5 elements, only vanadium has been identified as playing a role in the biological chemistry of living systems, but even it plays a very limited role in biology, and is more important in ocean environments than on land." (Wikipedia: Group 5 element, 1.12.21 UTC 06:58)

6. Chromium group


Chromium (24), Molybdenum (42), Tungsten (74), Seaborgium (106)

"Unlike other groups, the members of this family do not show patterns in its electron configuration, as two lighter members of the group are exceptions from the Aufbau principle." (Wikipedia: Group 6 element, 7.13.21 UTC 06:30)

7. Manganese group


Manganese (25), Technetium (43), Rhenium (75), bohrium (107)

"Only manganese has a role in the human body. It is an essential trace nutrient with the body containing approximately 10 milligrams at any given time... Technetium, rhenium and bohrium have no known biological roles." (Wikipedia: Group 7 element, 5.14.21 UTC 13:22)

8. Iron group


Iron (26), Ruthenium (44), Osmium (76), Hassium (108)

"The first three elements are hard silvery-white metals." (Wikipedia: Group 8 element, 4.6.21 UTC 10:57)

"Iron is a very common element that is used for things like steel and ferromagnetic properties. It is among the most common build materials of today." (Wikipedia: Group 8 element, 4.6.21 UTC 10:57)

9. Cobalt group


Cobalt (27), Rhodium (45), Iridium (77), Meitnerium (109)

"The first three elements are hard silvery-white metals." (Wikipedia: Group 9 element, 3.2.21 UTC 17:37)

10. Nickel group


Nickel (28), Palladium (46), Platinum (78), Darmstadtium (110)

"Group 10 metals are white to light grey in color, and possess a high luster, a resistance to tarnish (oxidation) at [standard temperature and pressure], are highly ductile, and enter into oxidation states of +2 and +4, with +1 being seen in special conditions." (Wikipedia: Group 10 element, 3.23.21 UTC 14:43)

11. Copper group


Copper (29), Silver (47), Gold (79), Roentgenium (111)

"All group 11 elements are relatively inert, corrosion-resistant metals... These elements have low electrical resistivity so they are used for wiring." (Wikipedia: Group 11 element, 7.25.21 UTC 15:43)

12. Zinc group


Zinc (30), Cadmium (48), Mercury (80), Copernicium (112)

"The group 12 elements are all soft, diamagnetic, divalent metals. They have the lowest melting points among all transition metals." (Wikipedia: Group 12 element, 6.38.21 UTC 15:30)

"While zinc is very important in the biochemistry of living organisms, cadmium and mercury are both highly toxic." (Wikipedia: Group 12 element, 6.38.21 UTC 15:30)

13. Boron group


Boron (5), Aluminum (13), Gallium (31), Indium (49), Thallium (81), Nihonium (113)

"Although situated in p-block, the group is notorious for violation of the octet rule by its members boron and (to a lesser extent) aluminum. These elements may place only six electrons (in three molecular orbitals) onto valence shell." (Wikipedia: Boron group, 7.29.21 UTC 19:49)

"Boron differs from the other group members in its hardness, refractivity and reluctance to participate in metallic bonding." (Wikipedia: Boron group, 7.29.21 UTC 19:49)

14. Carbon group


Carbon (6), Silicon (14), Germanium (32), Tin (50), Lead (82), Flerovium (114)

"Each of the elements in this group has 4 electrons in its outer shell... Those elements, especially carbon and silicon, have a strong propensity for covalent bonding, which usually brings the outer shell to eight electrons." (Wikipedia: Carbon Group, 8.12.21 UTC 15:34)

15. Pnictogens


Nitrogen (7), Phosphorus (15), Arsenic (33), Antimony (51), Bismuth (83), Moscovium (115)

"The pnictogens consist of two nonmetals (one gas, one solid), two metalloids, one metal, and one element with unknown chemical properties." (Wikipedia: Pnictogen, 6.8.21 UTC 16:16)

"This group has the defining characteristic that all the component elements have 5 electrons in their outermost shell, that is 2 electrons in the s subshell and 3 unpaired electrons in the p subshell." (Wikipedia: Pnictogen, 6.8.21 UTC 16:16)

"These elements are also noted for their stability in compounds due to their tendency for forming double and triple covalent bonds. This is the property of these elements which leads to their potential toxicity..." (Wikipedia: Pnictogen, 6.8.21 UTC 16:16)

16. Chalcogens


Oxygen (8), Sulfur (16), Selenium (34), Tellurium (52), Polonium, 84), Livermorium (116)

"Often, oxygen is treated separately from the other chalcogens, sometimes even excluded from the scope of the term 'chalcogen' altogether, due to its very different chemical behavior from sulfur, selenium, tellurium and polonium." (Wikipedia: Chalcogen, 6.29.21 UTC 13:36)

"All of the chalcogens have six valence electrons, leaving them two electrons short of a full outer shell." (Wikipedia: Chalcogen, 6.29.21 UTC 13:36)

"All of the solid stable chalcogens are soft and do not conduct heat well." (Wikipedia: Chalcogen, 6.29.21 UTC 13:36)

17. Halogens


Fluorine (9), Chlorine (17), Bromine (35), Iodine (53), Astatine (85), Tennessine (117)

"The group of halogens is the only periodic table group that contains elements in three of the main states of matter at standard temperature and pressure." (Wikipedia: Halogen, 8.17.21 UTC 15:27)

"Halogens are highly reactive, and as such can be harmful or lethal to biological organisms in sufficient quantities. This high reactivity is due to the high electronegativity of the atoms due to their high effective nuclear charge." (Wikipedia: Halogen, 8.17.21 UTC 15:27)

"All of the halogens form acids when bonded to hydrogen." (Wikipedia: Halogen, 8.17.21 UTC 15:27)

18. Noble gases


Helium (2), Neon (10), Argon (18), Krypton (36), Xenon (54), Radon (86), Oganesson (118)

"...they are all odorless, colorless, monatomic gases with very low chemical reactivity." (Wikipedia: Noble gas, 8.8.21 UTC 23:25)

"The noble gases have full valence electron shells... Atoms with full valence electron shells are extremely stable and therefore do not tend to form chemical bonds and have little tendency to gain or lose electrons." (Wikipedia: Noble gas, 8.8.21 UTC 23:25)

"The noble gases have weak interatomic force, and consequently have very low melting and boiling points." (Wikipedia: Noble gas, 8.8.21 UTC 23:25)

List of fields in mathematics

This post is a list of fields in mathematics. There are 19 fields listed below alphabetically. License: CC BY-SA 3.0

1. Algebra
"In its most general form, algebra is the study of mathematical symbols and the rules for manipulating these symbols; it is a unifying thread in almost all of mathematics." (Wikipedia: Algebra, 7.5.21 UTC 16:30)

2. Arithmetic
"Arithmetic is a branch of mathematics that consists of the study of numbers, especially the properties of the traditional operations on the them - addition, subtraction, multiplication and division, exponentiation and extraction of roots." (Wikipedia: Arithmetic, 8.6.21 UTC 00:20)

3. Calculus
"Calculus... is the mathematical study of continuous change..." (Wikipedia: Calculus, 8.5.21 UTC 10:26)

4. Category theory
"Category theory formalizes mathematical structure and its concepts in terms of a labeled directed graph called a category, whose nodes are called objects, and whose labelled directed edges are called arrows (or morphisms)." (Wikipedia: Category theory, 8.16.21 UTC 08:56)

5. Chaos theory
"Chaos theory is a branch of mathematics focusing on the study of chaos - states of dynamical systems whose apparently-random states of disorder and irregularities are often governed by deterministic laws that are highly sensitive to initial conditions. (Wikipedia: Chaos theory, 8.15.21 UTC 05:49)

6. Combinatorics
"Combinatorics is an area of mathematics primarily concerned with counting, both as a means and an end in obtaining results, and certain properties of finite structures." (Wikipedia: Combinatorics, 7.25.21 UTC 20:08)

7. Game theory
"Game theory is the study of mathematical models of strategic interaction among rational decision-makers." (Wikipedia: Game Theory, 8.10.21 UTC 19:27)

8. Geometry
"[Geometry] is concerned with properties of space that are related with distance, shape, size and relative position of figures." (Wikipedia: Geometry, 7.26.21 UTC 07:51)

9. Graph theory
"Graph theory is the study of graphs, which are mathematical structures used to model pairwise relations between objects. A graph in this context is made up of vertices (also called nodes or points) which are connected by edges (also called links or lines)." (Wikipedia: Graph theory, 8.5.21 UTC 01:45)

10. Group theory
"Group theory studies the algebraic structures known as groups. The concept of a group is central to abstract algebra: other well-known algebraic structures, such as rings, fields, and vector spaces, can all be see as groups endowed with additional operations and axioms." (Wikipedia: Group theory, 5.621 UTC 04:49)

11. Mathematical analysis
"Mathematical analysis is a the branch of mathematics dealing with limits and related theories such as differentiation, integration, measure, infinite series and analytic functions." (Wikipedia: Mathematical analysis, 7.24.21 UTC 07:10)

12. Mathematical logic
"Mathematical logic... is a subfield of mathematics exploring the applications of formal logic to mathematics... The unifying themes in mathematical logic include the study of the expressive power of formal systems and the deductive power of formal proof systems." (Wikipedia: Mathematical logic, 8.12.21 UTC 14:04)

13. Number theory
"Number theory is a branch of pure mathematics devoted primarily to the study of the integers and integer-valued functions." (Wikipedia: Number theory, 7.3.21 UTC 19:15)

14. Order theory
"Order theory is a branch of mathematics which investigates the intuitive notion of order using binary relations. It provides a formal framework for describing statements such as 'this is less than that' or 'this precedes that'." (Wikipedia: Order theory, 4.22.21 UTC 05:51)

15. Probability
"Probability is the branch of mathematics concerning numerical descriptions of how likely an event is to occur or how likely it is that a proposition is true." (Wikipedia: Probability, 8.16.21 UTC 12:52)

16. Representation theory
"Representation theory is a branch of mathematics that studies abstract algebraic structures by representing their elements as linear transformations of vector spaces, and studies modules over these abstract algebraic structures." (Wikipedia: Representation theory, 8.15.21 UTC 6:55)

17. Set theory
"Set theory is a branch of mathematical logic that studies sets, which informally are collections of objects." (Wikipedia: Set theory, 8.11.21 UTC 19:54)

18. Topology
"Topology is concerned with the properties of a geometric object that are preserved under continuous deformations, such as stretching, twisting, crumpling and bending; that is, without closing holes, opening holes, tearing, gluing, or passing through itself." (Wikipedia: Topology, 8.5.21 UTC 23:10)

19. Trigonometry
"Trigonometry is a branch of mathematics that studies relationships between side lengths and angels of triangles." (Wikipedia: Trigonometry, 8.9.21 UTC 2:39)

Tuesday, June 16, 2020

List of baseball hitters with at least 240 hits in a season


Photo source: Wikimedia Commons, Library of Congress

This post is a list of baseball hitters with at least 240 hits in a season in the MLB as of June 16th, 2020. There are 15 seasons listed below. The photo above is George Sisler in 1915.

1. Ichiro Suzuki (2004) - 262
2. Georg Sisler (1920) - 257
3. Lefty O'Doul (1929) - 254
3. Bill Terry (1930) - 254
5. Al Simmons (1925) - 253
6. Rogers Hornsby (1922) - 250
6. Chuck Klein (1930) - 250
8. Ty Cobb (1922) - 248
9. George Sisler (1922) - 246
10. Ichiro Suzuki (2001) - 242
11. Babe Herman (1930) - 241
11. Heine Manush (1928) - 241
13. Wade Boggs (1985) - 240
13. Jesse Burkett (1896) - 240
13. Darlin Erstad (2000) - 240