Monthly Archives: September 2018

Checklist for fixing up a used bicycle

The following checklist, inspired by Cycle Jam at the Canberra Environment Centre, is to make a used bicycle safe and rideable. It is just a minimum; it does not optimise a bike.

Frame should not have cracks. Frame should not be bent.
Handlebar should not rotate in clamp.
Handlebar clamp should not rotate relative to front wheel.
Brake levers and shifters should not rotate on the handlebar.
Both brakes should be securely attached to the frame.
Brake levers should not hit the handlebar.
Brake pads should hit the rim when the brake is pulled, not the wheel or the spokes. Brake pads should be more than 1mm thick. Brake cables should slide reasonably in their housing.
Wheels should not be so bent that either the brakes rub or the brake levers hit the handlebar and prevent braking. Spokes should not be broken or loose.
Wheels should not clunk side to side on axle. Preferably wheel bearings should not grind either.
Wheels should be seated in the dropouts properly.
Quick releases of wheels should be closed properly.
Headset should not clunk, preferably not grind either.
Bottom bracket should not clunk side to side, preferably not grind either.
Crankarms and pedals should not clunk on their attachment point, ideally pedal bearings should not grind.
Seatpost clamp securely fastened, quick release closed properly. Seat securely attached to seatpost.
Chainring bolts should be tight.
Tires pumped, not too worn or cracked. Valve stem straight (pointing to the hub).
Suspension (if any) working reasonably.

Check shifting into all gears front and rear. If problems, then:
Front derailleur should be securely attached to the frame at the correct height, not bent or angled wrong.
Front derailleur limit screws should not allow the chain to come off.
Rear derailleur securely attached to frame, not too bent.
Shifter cables should slide reasonably in their housing.
Chain should be neither too worn nor too long (sagging, too many links).

Seljakotist söömine

Reisidel ja matkadel on aeg-ajalt raske leida head istumiskohta (mis pole märg, must jne) lõunasöögiks. Seistes süües oleks aga vahel vaja toit või jook kuhugi asetada, et mõlemat kätt kasutada, näiteks uue toidukoti või karbi avamiseks. Sobivat asetuskohta toidule ei pruugi samuti lihtne leida olla, eriti kui on tuuline, vihmane või ümberringi palju näljaseid elajaid (kajakad, sipelgad jne).
Lihtne nipp on seljakott kõhu peale vahetada ja kas selle pealset kandikuna kasutada või selle seest toidukotist-karbist süüa. Seljakoti küljetaskud on sobivad joogihoidjad, vahel selleks mõeldudki. Kui seistes jahe on või hakkavad sipelgad jalgadel ronima, saab süües ka edasi kõndida, mis neid probleeme vähendab.

Pakendite kasutamine prügikotina

Ilmselt pole ma ainuke, kes selle nipi peale on tulnud, aga mitmesuguseid pakendeid saab kasutada prügikotina, nii et ei pea eraldi prügikotte ostma. See annab pakendile ühe taaskasutuse juurde ja on väike rahaline kokkuhoid. Keskkonnasõbralikkus oleneb sellest, kas prahi jaoks kasutatavaid pakendeid saaks mingil paremal viisil taaskasutada.
Kilekotte (leiva, kuivainete, puuvilja jne) on kõige lihtsam prügikotina kasutada, aga selleks sobivad ka plastkarbid (vahtplastist lihakandik, puuviljakarp) ja pakkekile (juustu, juurvilja). Pakkekile saab lauale laotada ja prügi sellele kuhjata, misjärel saab kile nurkadest kotiks kokku voltida. Kile kleepub iseenda külge, nii et kott lihtsasti ei lagune. Väga märga prügi pakkekilele laotades hakkab vedelik sellelt maha nirisema, nii et vedela prügi jaoks kile ei sobi. Samas, sarnane probleem on ka prügikottidel: kilekotti märja prahi panemisel peab hoolega aukude puudumist kontrollima ja muu prahi seas ei tohi teravaid esemeid olla, mis prügikotti hiljem augu teevad.
Väikeste pakendite prügikotina kasutamisel on see eelis, et prügi ei seisa soojas toas kuni suur kott täitub (soojas seistes kipub prahil hais tekkima). Iga kord kodust väljudes saab tekkinud väikese prügikoguse ära visata (tavaliselt vähemalt kord päevas). Väikepakendi puudus on muidugi suuremõõduliste asjade mittemahtumine, aga need saab tavaliselt eraldi ära visata.

Poaching reduction using lab-grown ivory

Poachers kill elephants for tusks and rhinos for horns because these can be sold for a high price on the black market. The killing has occurred both in the wild and in zoos, and thieves have broken into nature museums to steal rhino horns from exhibits. Sometimes news reports describe how police crush or burn seized illegal ivory, which seems counterproductive, because it reduces supply and thus drives up the price. A higher price increases future poaching. Perhaps the police are in the pay of some illegal ivory dealers and are deliberately helping drive up the price by destroying competing dealers’ products.
Instead, the price of ivory and rhino horn should be reduced so that poaching becomes unprofitable. Many organs have been grown in the lab using a collagen scaffold seeded with stem cells from the appropriate tissue (bladder, skin, heart). Growing elephant tusks or rhino horns in the lab should be feasible using similar techniques. Flooding the market with cheap lab-grown horns and tusks would eliminate the incentive to poach.
The demand for ivory and rhino horn is mostly due to silly beliefs about their medicinal properties, so the buyers may not want lab-grown substitutes, believing these to be ineffectual (which these are, just like wild-type horns and tusks). In this case, the lab-grown horns and tusks should be made indistinguishable from animal-derived ones and inserted into the illegal supply chain covertly. The dealers on the black market are not too honest people and would probably be happy to lie to their customers that lab-grown products are from wild animals.