Marine biology: Osedax, also known as zombie worms

Osedax worms, also known as zombie worms, are bone-eating worms [1]; the Latin-derived word “Osedax” means “bone devourer.” Crispin Little explains [2]:

Zombie worms, also known as Osedax (Latin for “bone devourer”), grow “roots” in dead whale bones, which they slowly consume. The worms seem to live exclusively at whale falls. […] A least five different species of Osedax have been discovered so far.

One species, Osedax rubiplumus, has been found on an almost decomposed gray whale carcass (lying 2,891 meters deep) in Monterey Bay, California, where they, along with sea cucumbers, are scavenging the remaining whale bones (see page 82 in [2]).

Osedax worms leave borings in dead whale bones. A fossil specimen of such an Osedax-marked bone has yet to be found.

Nomenclature/taxonomy:
Genus: Osedax < Family: Siboglinidae < Order: Sabellida < Class: Polychaeta < Phylum: Annelida < Kingdom: Animalia

Keywords: marine annelid worms, ecosystems, biodiversity, deep seafloor, scavenger stages, sulfophilic stage

References
[1] Monterey Bay Aquarium Research Institute: Osedax, the bone-eating worms.
[2] Crispin T. S. Little: The Prolific Afterlife of Whales. Scientific American February 2010, 302 (2), pp. 78-84.

Marine biology: Osteopelta (small, bone-associated shield), limpets

Osteopelta is the name for a specialized group of limpets. The word is derived from the Greek/Latin noun pelta, meaning small shield, and the prefix osteo- from the the Greek word osteon for bone (as occurring, for example, in the word osteoporosis). Osteopelta limpets have been found in assocoation with bones (!): alive on bones of whale carcasses sunken to the seafloor [1] and fossilized along with bones of a leatherback turtle from the Middle Eocene [2].
Crispin Little refers to the discovery of Osteopelta in recovered whale bones [1]:

[…] a tiny, previously unknown species of limpet—limpets are snail-like mollusks with conical rather than spiral shells—was described in 1985, soon followed by others. The limpets were named Osteopelta bacause of their association with bones.

Keywords: Osteopeltidae, ecosystems, biodiversity, deep seafloor, scavenger stages, fossil bones

References:
[1] Crispin T. S. Little: The Prolific Afterlife of Whales. Scientific American February 2010, 302 (2), pp. 78-84.
[2] Craig R. Smith and Amy R. Baco: Ecology of Whale Falls at the Deep-Sea Floor. Oceanography and Marine Biology: an Annual Review 2003, 41, pp. 311-354 (see page 343) .PDF.

Legionella pneumophila and Legionnaires' disease

Legionella pneumophila is a bacterial pathogen, which causes diseases such as Pontiac fever and Legionnaires' disease, also known as Legion Fever. Legionella pathogens, like some other bacteria, evolved by protecting themselves from attacks by single-celled organisms in soils such as soil amoebas, which were playing the key role in giving the title bacteria and disease their names [1]:

At an American Legion meeting in Philadelphia in 1976, amoebas containing Legionella bacteria were blown through air-conditioning ducts into the hotel and delivered deep into the conventioneer's lungs. Macrophages [white blood cells within tissues] in the humans' alveoli [primary sites of gas exchange with the blood in the respiratory system] ingested the Legionella, much as an amoeba would. Thirty-four people died of the resulting respiratory illness, and Legionnaires' disease was born.

Keywords: history, nomenclature, microbiology, legionellosis

Reference
[1] B. Brett Finlay: The Art of Bacterial Warfare. Scientific American February 2010, Volume 302, Number 2, pp. 57-63.

Acronym in photovoltaics: XSC for excitonic solar cell

When it comes to acronym building, the letter x is sometimes the preferred or alternate letter of a word or an affix to be carried over into the acronym—regardless of x's position in the former. For example, the acronym for extensible markup language is XML (instead of EML). The acronym XSC (but also ESC) has been used for excitonic solar cell [1].
XSCs—in contrast to conventional solar cells—function by a different mechanism involving the generation, diffusion and dissociation of excitons (see The noun exciton and the adjective excitonic).

Keywords: photovoltaic devices, solar cells, exciton

Reference
[1] Brian A. Gregg: The Photoconversion Mechanism of Excitonic Solar Cells. MRS Bulletin January 2005, 30, 20-22. PDF.

The noun exciton and the adjective excitonic

The word exciton derives from the noun excitation and the suffix -on [1-3]. This suffix in exciton equals the preposition “on” and makes one think exciton is short for “the excitation is on,” but the suffix -on indicates that we are talking about a sub-nanoscale object of the wave-particle world (compare with the nouns photon, phonon, electron, proton, neutron, etc.).
An exciton is a bound electron-hole pair that originates, diffuses and dissociates inside—or at the interface of—a crystal. Direct observation of excitons is difficult [4]:

Because the [negative] electron and the positive hole have equal but opposite electrical charges, the exciton as a whole has no net electrical charge (though it transports energy). This makes excitons difficult to detect, but detection is possible by indirect means.

The adjective excitonic is used to specify materials or devices in which excitons can occur or play a critical role in their function. An excellent example are excitonic solar cells for converting light into electrical energy [5,6]. No surprise, there is a lot of excitement about excitons.

The English noun exciton in other languages
French: exciton
German: Exziton (neuter)
Italian: eccitone
Portuguese: exciton
Spanish: excitón

References
[1] www.merriam-webster.com/dictionary/Exciton
[2] www.myetymology.com/english/exciton.html
[3] www.wordnik.com/words/exciton/etymologies
[4] www.britannica.com/EBchecked/topic/197803/exciton
[5] Allon I. Hochbaum and Peidong Yang: Semiconductor Nanowires for Energy Conversion. Chem. Rev. 2010, 110, pp. 527-546 (see pages 531 to 536 on excitonic solar cells).
DOI: 10.1021/cr900075v
[6] Brian A. Gregg: The Photoconversion Mechanism of Excitonic Solar Cells. MRS Bulletin January 2005, 30, 20-22. PDF.

DecaBDE, short for decabromodiphenyl ether

The flame retardant decabromodiphenyl ether (C12Br10O) is often addressed by its short name decaBDE, sometimes spelled deca-BDE. It is also encoded as BDE-209. Other names are bis(pentabromophenyl)ether and its IUPAC name:
2,3,4,5,6-pentabromo-1-(2,3,4,5,6-pentabromophenoxy)benzene.

DecaBDE is a perbrominated aromatic ether compound. Based on studies exposing the risks for human health and the environment due to decaBDE's potential for bioaccumulation and degradation into toxic products, three companies are now phasing out the production of this chemical [1,2]. Alternatives have been evaluated [3].

Identifiers for decabromodiphenyl ether:
CAS Registry Number: 1163-19-5
EINECS Number: 214-604-9
RTECS Number: KN352500
Beilstein Number: 2188438

Decabromodiphenyl ether in other languages:
French: oxyde de bis(pentabromophényle)
German: Bis(pentabromphenyl)ether
Spanish: bis(pentabromofenil)éter

References
[1] Glenn Hess: Industry Drops Flame Retardant. Chemical & Engineering News January 4, 2010, 88 (1), page 10.
[2] DecaBDE Study: A Review of Available Scientific Research. Illinois Environmental Protection Agency. HTML.
[3] Report on Alternatives to the Flame Retardant DecaBDE: Evaluation of Toxicity, Availability, Affordability, and Fire Safety Issues. Illinois Environmental Protection Agency, March 2007. PDF.

Synfuel, short for synthetic fuel

The noun synfuel derives from the adjective synthetic and the noun fuel. A synfuel is a liquid or gaseous fuel derived especially from a fossil fuel that is a solid (as coal) or part of a solid (as tar sand or oil shale) [1].
Synfuels are considered as alternatives to liquid oil, which—within this terminology—is a natfuel (naturally occurring fossil fuel). Coal, oil shale, and tar sand, which all are low state grade energy resources, can be converted by industrial processes into higher state grade resources with the goal to replace natfuel-oil. However, this is inefficient and environmentally problematic. Douglas Reynolds has discussed the economics of oil alternatives and explains [2]:

Since they [synfuels] start out as low state grades, they require expensive transformations before firms can convert them into liquid or gas that could be used in the oil substitutes EUC [energy utilization chain]. Usually, oil from synfuel is three times as labor-to-energy intensive and 10 times as capital-to-energy intensive as crude oil (Rocks, 1989) [Lawrence Rocks: Fuels for tomorrow. Pennwell Corp., Tulsa, OK, December 1980]. Again we get the entropy subsidy problem, where when fuel prices go up, so do labor and material prices. These input prices in turn cause the labor- and material-intensive synfuels [boldface mine] to cost more than originally expected. Thus, any attempt to estimate the cost of synfuels is automatically an incorrect cost, because it does not nor cannot account for the entropy subsidy problem.

Keywords: etymology, energy, technology, resources, oil substitutes, synthetic fuels

References
[1] www.merriam-webster.com/dictionary/synfuel
[2] Douglas B. Reynolds: The Energy Utilization Chain: Determining Viable Oil Alternative Technology. Energy Sources 2000, 22, pp. 215-226.