Macroreplantations of the upper extremity: a series of 11 patients

INTRODUCTION Micro- or macroreplantation is classified depending on the level of amputation, distal or proximal to the wrist. This study was performed to review our experience in macroreplantation of the upper extremity with special attention to technical considerations and outcomes. MATERIALS AND METHODS Between January 1990 and December 2010, 11 patients with a complete amputation of the upper extremity proximal to the wrist were referred for replantations to our department. The patients, one woman and ten men, had a mean age of 43.4 ± 18.2 years (range 19-76 years). There were two elbow, two proximal forearm, four mid-forearm, and three distal forearm amputations. The mechanism of injury was crush in four, crush-avulsion in five and guillotine amputation in two patients. The Chen classification was used to assess the postoperative outcomes. The mean follow-up after macroreplantation was 7.5 ± 6.3 years (range 2-21 years). RESULTS All but one were successfully replanted and regained limb function: Chen I in four cases (36 %), Chen II in three cases (27 %), Chen III in two cases (18 %), and Chen IV in one patient (9 %). We discuss the steps of the macroreplantation technique, the need to minimize ischemic time and the risk of ischemia reperfusion injuries. CONCLUSION Thanks to improvements in technique, the indications for limb preservation after amputation can be expanded. However, because of their rarity, replantations should be performed at specialist replantation centers. LEVEL OF EVIDENCE Level IV.

Air-Sea Interactions During the Passage of a Winter Storm Over the Gulf Stream: A Three-Dimensional Coupled Atmosphere-Ocean Model Study

A three-dimensional, regional coupled atmosphere-ocean model with full physics is developed to study air-sea interactions during winter storms off the U. S. east coast. Because of the scarcity of open ocean observations, models such as this offer valuable opportunities to investigate how oceanic forcing drives atmospheric circulation and vice versa. The study presented here considers conditions of strong atmospheric forcing (high wind speeds) and strong oceanic forcing (significant sea surface temperature (SST) gradients). A simulated atmospheric cyclone evolves in a manner consistent with Eta reanalysis, and the simulated air-sea heat and momentum exchanges strongly affect the circulations in both the atmosphere and the ocean. For the simulated cyclone of 19-20 January 1998, maximum ocean-to-atmosphere heat fluxes first appear over the Gulf Stream in the South Atlantic Bight, and this results in rapid deepening of the cyclone off the Carolina coast. As the cyclone moves eastward, the heat flux maximum shifts into the region near Cape Hatteras and later northeast of Hatteras, where it enhances the wind locally. The oceanic response to the atmospheric forcing is closely related to the wind direction. Southerly and southwesterly winds tend to strengthen surface currents in the Gulf Stream, whereas northeasterly winds weaken the surface currents in the Gulf Stream and generate southwestward flows on the shelf. The oceanic feedback to the atmosphere moderates the cyclone strength. Compared with a simulation in which the oceanic model always passes the initial SST to the atmospheric model, the coupled simulation in which the oceanic model passes the evolving SST to the atmospheric model produces higher ocean-to-atmosphere heat flux near Gulf Stream meander troughs. This is due to wind-driven lateral shifts of the stream, which in turn enhance the local northeasterly winds. Away from the Gulf Stream the coupled simulation produces surface winds that are 5 similar to 10% weaker. Differences in the surface ocean currents between these two experiments are significant on the shelf and in the open ocean.

Ethnolinguistic survey of westernmost Arunachal Pradesh: A field worker's impressions

The area between Bhutan in the west, Tibet in the north, the Kameng river in the east and Assam in the south is home to at least six distinct phyla of the Trans-Himalayan (Tibeto-Burman, Sino-Tibetan) language family. These phyla encompass a minimum of 11, but probably 15 or even more mutually unintelligible languages, all showing considerable internal dialect variation. Previous literature provided largely incomplete or incorrect accounts of these phyla. Based on recent field research, this article discusses in detail the several languages of four phyla whose speakers are included in the Monpa Scheduled Tribe, providing the most accurate speaker data, geographical distribution, internal variation and degree of endangerment. The article also provides some insights into the historical background of the area and the impact this has had on the distribution of the ethnolinguistic groups.

Continental-Scale Footprint of Balancing and Positive Selection in a Small Rodent (Microtus arvalis)

Genetic adaptation to different environmental conditions is expected to lead to large differences between populations at selected loci, thus providing a signature of positive selection. Whereas balancing selection can maintain polymorphisms over long evolutionary periods and even geographic scale, thus leads to low levels of divergence between populations at selected loci. However, little is known about the relative importance of these two selective forces in shaping genomic diversity, partly due to difficulties in recognizing balancing selection in species showing low levels of differentiation. Here we address this problem by studying genomic diversity in the European common vole (Microtus arvalis) presenting high levels of differentiation between populations (average FST = 0.31). We studied 3,839 Amplified Fragment Length Polymorphism (AFLP) markers genotyped in 444 individuals from 21 populations distributed across the European continent and hence over different environmental conditions. Our statistical approach to detect markers under selection is based on a Bayesian method specifically developed for AFLP markers, which treats AFLPs as a nearly codominant marker system, and therefore has increased power to detect selection. The high number of screened populations allowed us to detect the signature of balancing selection across a large geographic area. We detected 33 markers potentially under balancing selection, hence strong evidence of stabilizing selection in 21 populations across Europe. However, our analyses identified four-times more markers (138) being under positive selection, and geographical patterns suggest that some of these markers are probably associated with alpine regions, which seem to have environmental conditions that favour adaptation. We conclude that despite favourable conditions in this study for the detection of balancing selection, this evolutionary force seems to play a relatively minor role in shaping the genomic diversity of the common vole, which is more influenced by positive selection and neutral processes like drift and demographic history.

Solar radiation over and under sea ice and photographic quantification of Ice algal aggregates during the POLARSTERN cruise ARK-XXVII/3 (IceArc) in summer 2012

The ice cover of the Arctic Ocean has been changing dramatically in the last decades and the consequences for the sea-ice associated ecosystem remain difficult to assess. Algal aggregates underneath sea ice have been described sporadically but the frequency and distribution of their occurrence is not well quantified. We used upward looking images obtained by a remotely operated vehicle (ROV) to derive estimates of ice algal aggregate biomass and to investigate their spatial distribution. During the IceArc expedition (ARK-XXVII/3) of RV Polarstern in late summer 2012, different types of algal aggregates were observed floating underneath various ice types in the Central Arctic basins. Our results show that the floe scale distribution of algal aggregates in late summer is very patchy and determined by the topography of the ice underside, with aggregates collecting in dome shaped structures and at the edges of pressure ridges. The buoyancy of the aggregates was also evident from analysis of the aggregate size distribution. Different approaches used to estimate aggregate biomass yield a wide range of results. This highlights that special care must be taken when upscaling observations and comparing results from surveys conducted using different methods or on different spatial scales.

Rb-Sr and K-Ar data for Upper Vendian clayey rocks of the Russian Platform

Geochemical behavior of Rb-Sr and K-Ar systems in Upper Vendian clayey rocks of the Russian Platform is under consideredation. The use of additional data on grain size fractions of sedimentary rocks recovered from boreholes drilled in the Gavrilov Yam area made it possible to confirm the previous conclusion on two stages of epigenetic matter transformation (approximately 600 and 400 Ma ago). Distortions are related to transformation of sediments due to interaction in the water-rock system. Interaction degree was more intense in the upper part of the sedimentary section relative to its lower strata. These conclusions are substantiated by materials from boreholes that characterize different types of Vendian sections and different tectonic zones.

Geotechnical properties at DSDP Leg 66 Holes

Delineating the interrelationships between tectonics, sedimentation, and geotechnical properties is particularly important for areas subjected to the dynamic affects of convergence. DSDP Leg 66 drilling within the Middle America Trench complex provided a unique opportunity to investigate these interrelationships along a transect of eight drill sites beginning on the trench outer slope and traversing the trench, trench inner slope, and upper continental slope. Investigations of other convergent margins suggest that deformation occurs most rapidly along the lower trench inner slope and is reflected by the geotechnical properties (Carson, 1977; Seely, 1977; and von Huene, 1979). This study focuses on the geotechnical properties of Middle America Trench sediments and the possible affects of convergence on these properties.

(Table 2) Comparative growth rates of upper and lower parts of Fe-Mn nodules from the Pacific Ocean

Dates and growth rates of iron-manganese nodules obtained by various direct and indirect methods, including radiometric, micropaleontological, geological and experimental, are discussed. Validity of assumptions, on which the radiometric dating of nodules is based and reliability of results are discussed. The problem of "buoyancy" of slow-growing nodules resting on the surface of faster-accumulating sediments is considered: It may be caused by action of deep-water fauna, bottom currents, or plastic properties of sediments.

Reconstruction of sea surface temperature and salinity of the Arabian Sea

High-frequency suborbital variations (Dansgaard-Oeschger cycles) characterize the climatic history of the Northern Hemisphere as observed in Greenland ice cores, deep-sea sediments of the North Atlantic, the Californian borderland, the Arabian Sea, the South China Sea, and the Chinese loess area. Paleoceanographic data from core KL126 from the Bay of Bengal in combination with data from the other Asian monsoonal areas indicate that the feedback processes involving snow and dust of the Tibetan Plateau vary the summer monsoon capacity to transport moisture into central South Asia and into the atmosphere. We postulate that the summer monsoon initiates, amplifies, and terminates these cycles in the Northern Hemisphere.

(Table 1) Contents of chlorophyll a over the Northern Sea Route according to data of field measurements and estimated from MODIS data on measurement days

New maps of mean monthly distribution of chlorophyll and primary production in the Kara Sea were compiled using joint processing of CZCS (1978-1986), SeaWiFS (1998-2005), and MODIS (2002-2006) satellite data and field measurements. The annual primary production of phytoplankton is estimated at 22.3 x 10**6 t C per year or 70 mg C/m**2 per day. Results of calculations of the organic carbon budget in the Kara Sea are presented.