The highly fragmented and distorted skull of the adult skeleton ARA-VP-6/500 includes most of the dentition and preserves substantial parts of the face, vault, and base. Anatomical comparisons and micro–computed tomography–based analysis of this and other remains reveal pre- Australopithecus hominid craniofacial morphology and structure. The Ardipithecus ramidus skull exhibits a small endocranial capacity (300 to 350 cubic centimeters), small cranial size relative to body size, considerable midfacial projection, and a lack of modern African ape–like extreme lower facial prognathism. Its short posterior cranial base differs from that of both Pan troglodytes and P. paniscus . Ar. ramidus lacks the broad, anteriorly situated zygomaxillary facial skeleton developed in later Australopithecus . This combination of features is apparently shared by Sahelanthropus , showing that the Mio-Pliocene hominid cranium differed substantially from those of both extant apes and Australopithecus .

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The extremely small endocranial volume (ECV) of LB1, the type specimen of Homo floresiensis, poses a challenge in our understanding of human brain evolution. Some researchers hypothesize dramatic dwarfing of relative brain size from Homo erectus presumably without significant decrease in intellectual function, whereas others expect a lesser degree of brain diminution from a more primitive, small-brained form of hominin currently undocumented in eastern Asia. However, inconsistency in the published ECVs for LB1 (380-430 cc), unclear human intraspecific brain-body size scaling and other uncertainties have hampered elaborative modelling of its brain size reduction. In this study, we accurately determine the ECV of LB1 using high-resolution micro-CT scan. The ECV of LB1 thus measured, 426 cc, is larger than the commonly cited figure in previous studies (400 cc). Coupled with brain-body size correlation in Homo sapiens calculated based on a sample from 20 worldwide modern human populations, we construct new models of the brain size reduction in the evolution of H. floresiensis. The results show a more significant contribution of scaling effect than previously claimed.

All fungi use multiple mitogen-activated protein kinase (MAPK) cascades to respond to external signals to regulate specialized responses. In this study, we cloned and characterized a putative MAPKKK gene ChSte11, orthologous to yeast STE11, of Cochliobolus heterostrophus. DeltaChste11 strains showed defects in conidiation, sexual development, melanization and the formation of appressoria. These mutants were significantly less virulent on corn plants than the wild type. Similar phenotypes were observed in mutants of Chk1-MAPK, a putative downstream protein kinase of ChSte11. These results suggested that ChSte11 regulates various morphological changes and pathogenicity via Chk1 MAPK. Both DeltaChste11 and Deltachk1 strains showed severe sensitivity to oxidative stress, hydrogen peroxide, and heavy metals, cupric or ferric cations. DeltaBmhog1 strains, mutants of the HOG1-type MAPK, did not show sensitivity to these forms of stress. Our results strongly suggested that the Ste11-type MAPKKK regulates not only various morphological changes and pathogenicity, but also adaptations to stress via Chk1-type MAPK in filamentous fungi.

A QTW VTOL UAV, featured tandem tilt wings and propellers mounted at the mid-span of each wing, is one of the most promising UAV configurations having both a VTOL capability and high cruise performance. A small prototype QTW UAV has been constructed to prove the concept and full transition between vertical and horizontal flight has been successfully demonstrated under remote manual control. The essential aerodynamic characteristics of the QTW derived from wind tunnel data are summarized in this paper, and a tandem wing concept which achieves both hovering and cruising stability has been applied to design the prototype UAV. A flight control system allowing continuous control through all flight phases enabled a pilot to perform vertical takeoff , accelerating transition, cruise, decelerating transition and hover landing, with sufficient flying qualities.