Orientation and slope preference in barrel cactus (Ferocactus acanthodes) at its northern distribution limit

Journal ArticleMicrosite distribution and diurnal tissue temperature fluctuations were measured in Ferocactus acanthodes (barrel cactus) at its northern distribution limit in the Beaver Dam Mountains of southwestern Utah. At this location, barrel cacti were limited to south-facing slopes. Orientation (azimuth and angle) of both the cactus stem and of the apical region at the top of the cactus were nonrandom, strongly facing south. The potential adaptive significance of this orientation in minimizing apical meristematic tissue damage under low wintertime conditions and minimizing high temperature damage under summertime conditions is discussed

Perceptions of knowledge sharing among small family firm leaders: a structural equation model

Small family firms have many unique relational qualities with implications for how knowledge is passed between individuals. Extant literature posits leadership approach as important in explaining differences in knowledge-sharing climate from one firm to another. This study investigates how leadership approaches interact with family influence to inform perceptions of knowledge sharing. We utilize survey data (n = 110) from owner-managers of knowledge-intensive small family firms in Scotland. Our findings present a choice in leadership intention, contrasting organization-focused participation against family-influenced guidance. Insight is offered on the implications of this leadership choice at both organizational and familial level

CLOTHING FOR FIRE PROTECTION AND THEIR EVALUATION

U ekstremnim radnim uvjetima, gdje su radnici različitog profila (vatrogasci, radnici na palubama nosača zrakoplova, radnici u kotlovnicama, spasioci, vojnici, itd.) izloženi nastanku i pojavi vatre, od osnovnog značaja su zaštitni odjevni sustavi koji utječu na zaštitu korisnika, učinkovitost tijekom rada i udobnost. Važno je poznavati da li i u kolikoj mjeri se sa zaštitnim odjevnim sustavima štiti korisnik od djelovanja zdravlju štetnim utjecajima i kako takvi sustavi utječu na njegovo zdravlje zbog (ne)udobnosti tijekom rada. U ovom radu prikazan je odjevni sustav za zaštitu od požara koji je vrednovan pomoću požarne lutke (engl. thermo man) sa simulacijom eksplozivne vatre. Analize takvih testiranja obuhvaćaju vrednovanje stupnja opeklina te mogućnost, da korisnik preživi ili ne, kod upotrebe dviju različitih kombinacija zaštitnih odjevnih sustava koji se upotrebljavaju na palubama vojnih brodova Kraljevske mornarice Velike Britanije. Spomenuti odjevni sustavi namijenjeni su za rad na palubama za uzlijetanje, kao i za općenitu uporabu, i predstavljaju određenu mjeru zaštite od požara i povećavaju mogućnost micanja iz požarnog područja. Odjevni sustavi se međusobno razlikuju po vanjskom gornjem sloju, zapaljivom odijelu FWC (engl. foul weather clothing) i nezapaljivom odijelu Perfectos FWC, odnosno po njegovoj nezapaljivosti, paropropusnosti, udobnosti i utjecaju na kretanje prilikom nošenja. Oba odjevna sustava tijekom testiranja bila su izložena vatri određeno vrijeme i to 4, 6 ili 8 sekundi. Iz prikazanih rezultata utvrđeno je da je zapaljivo odijelo FWC primjereno za uporabu na palubama za uzlijetanje zrakoplova, jer je zaštita pri izloženosti plamenu za vrijeme 6 sekundi jednaka zaštiti nezapaljivog odijela Perfectos FWC.In extreme work conditions where workers are exposed to fire (firemen, workers at aircraft-carrying ships, workers in boiler rooms, rescuers, military troupes, etc.) protective clothing is of singular importance in ensuring user protection, comfort and work efficacy. It is important to know how much protective clothing in fact protects users from harmful environments and how they affect user\u27s health and comfort in the course of work. The paper discusses the fire-fighter’s clothing evaluated by means of a thermo man in the situation of simulated explosive fire. Tests such as this one have given some indication of the possible degree of burns and of user survival when using two different combinations of protective clothing used on navy ships of the Royal Navy in Great Britain. These clothes are intended for work at take-off strips on ships and for general use. They provide certain protection from fire and increase the chance of removal from fire-affected zones. The clothes differ in the outer flammable layer of the FWC (foul weather clothing) and non-flammable Perfectos FWC, i.e. in their resistance to fire, degree of ventilation, comfort and effect on movement while worn. Both types of clothing were exposed to fire in the tests for a duration of 4, 6 and 8 seconds. The results show that the flammable FWC was suitable for use at take-off strips on ships, as the protection in exposure to flame for 6 seconds is equal to the protection provided by the non-flammable clothes Perfectos FWC