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The aim of this study was to compare accuracy of surgical plans generated from in-person and telemedicine evaluations and assess the reasons for surgical plan changes between initial evaluation and surgery. The secondary objective was to assess the effect of changes in surgical planning on postoperative outcomes.In this retrospective cohort study, consecutive patients who were evaluated as new patients by orthopaedic spine faculty between 2019 and 2021 were divided by appointment type: telemedicine (n = 39) and in-person (n = 92). Patients were included if the surgeon documented a definitive surgical plan at the initial visit. The primary outcome was change in surgical plan from initial assessment to actual procedure performed.There was no significant difference in the accuracy of initial surgical plans between the telemedicine and in-person cohorts (79.5% vs. 82.6%, P = 0.673). The most common modification in the surgical plan (79%) was change in the number of operated levels, of which 18 of 19 patients had 1 added operated level. Less common reasons were change in approach (13%) and change in procedure (8%). Patients with changes to their surgical plan experienced longer length of stay (3.1 vs. 2.0 days, P = 0.027) than patients with consistent surgical plans.Telemedicine and in-person evaluations generated similarly accurate surgical plans. Changes to the initial surgical plans most often involved adding operative levels. Our findings show that telemedicine visits are an acceptable option for preoperative assessment to generate surgical plans; however, further research is needed.

The loss of surface vegetation and reduced infiltration caused by wildfires can trigger gully rejuvenation, resulting in damage to downstream aquatic resources and risk to human life and property. We developed a spatially explicit metric of burn severity — the Burn Severity Distribution Index (BSDI) — and tested its ability to predict post-fire gully rejuvenation in 1st and 2nd order basins burned in the 2000 Valley Complex fires in the Sapphire Mountains of western Montana. The BSDI was derived from burn severity data interpreted from Landsat 7 satellite imagery using the Normalized Burn Ratio (NBR) method, and ranged from 0.0 for completely unburned basins to 4.0 for basins burned entirely at high severity. In July 2001 rainstorms with peak 30-minute intensities of up to 17 mm h− 1 triggered gully rejuvenation in 66 of the 171 basins examined. The frequency of gully rejuvenation was higher in basins with higher BSDI values, increasing from zero for basins with a BSDI less than 1.3 to 67% for basins with a BSDI greater than 3.0. Binary logistic regression indicated that BSDI was a more significant predictor of gully rejuvenation than basin morphometric variables. The absence of gully rejuvenation in several basins with a high BSDI was attributed to low gradient, dense riparian vegetation, or concentration of high burn severity at lower elevations in the basin. The presence of gully rejuvenation in several basins with a low BSDI was associated with false negative NBR classification errors in northwest aspects, and concentration of severe burn impacts in the drainage headslopes. BSDI is a useful metric for predicting gully rejuvenation after wildfire. The use of the BSDI in Burned Area Emergency Response team assessments could improve the planning, implementation, and monitoring of burned area recovery treatments.

Tankersley and Munson (1992) reiterate that the early and, perhaps, some of the later Meadowcroft Rockshelter radiocarbon dates may be contaminated by anthropogenically derived coal or dissolved coal by-products. Their allegations are assessed in light of available data and rejected. Presently, there is no evidence whatsoever for particulate or nonparticulate contamination of any part of the Meadowcroft Rockshelter radiocarbon chronology.

Ever since the publication of the first of more than 50 internally consistent radiocarbon dates from Meadowcroft Rockshelter (36 WH297), controversy has been generated by frequent assertions that the dates older than 11,000 B.C. have suffered particulate or nonparticulate contamination. Data bearing on these assertions are assessed in the light of accelerator mass spectroscopy (AMS) dates provided by Oxford University. The weight of all data taken together suggests that this site still represents the best-dated evidence for the presence of human beings south of the glacial front in the Americas. That evidence indicates that Native Americans were present in southwestern Pennsylvania by 14,000–14,500 years ago.

Thin sections from 44 sherds representing eight prehistoric sites on four islands (Barbuda, Montserrat, Anguilla, St. Martin) in the northern Lesser Antilles (West Indies) were examined using a petrographic microscope. Point counting distinguished three temper associations: (1) exclusively volcanic, (2) volcanic and carbonate, and (3) volcanic, carbonate, and grog. Exclusively volcanic or dominantly volcanic (with low carbonate) temper associations occur in all Saladoid and many post-Saladoid sherds, with plagioclase feldspar and volcanic rock fragments being most abundant. Thin sections with significant carbonate content or with grog were restricted to post-Saladoid sherds from Barbuda and to a lesser extent Anguilla. The presence of volcanic grains in sherds from the limestone islands of Barbuda and Anguilla indicates that volcanic islands in the region served as sources of pottery (or volcanic temper) for these two islands.

This volume covers the geological aspects of archaeology from both regional and topical perspectives in an attempt to reflect the diverse and heterogeneous nature of archaeological geology. Of the 28 chapters, some are site-specific archaeological investigations that typify a variety of other sites: for example, the Commins site, Canada; the Calico site, California; and the Teotihuacan site, Mexico. Others summarize the archaeological geology of regions such as Alaska, western Canada, glacial Lake Agassiz basin, the central and southern Great Plains, or the North American continental shelf. Others focus more generally on topics such as the old copper industry of the continent, point-bar geoarchaeology of the Savannah River valley, and molluscs and coastal archaeology. Finally, a section on techniques includes chapters on geophysics, isotope geochemistry, pedology, and stratigraphic nomenclature as each applies to archaeology.

Meadowcroft Rockshelter is a deeply stratified multicomponent site in Washington County, southwestern Pennsylvania. The 11 well-defined stratigraphic units identified at the site span at least 16,000 years and perhaps 19,000 years of intermittent occupation by groups representing all of the major cultural stages/periods now recognized in northeastern North America. Throughout the extant sequence, the site served as a locus for hunting, collecting, and food-processing activities, which involved the seasonal exploitation of the immediately adjacent Cross Creek Valley and contiguous uplands. Presently, Meadowcroft Rockshelter represents one of the earliest well-dated evidences of man in the New World as well as the longest occupational sequence in the Western Hemisphere.

The science of paleoecology suffers from a lack of conceptual frameworks. Paleoecologists have been overconcerned with the inadequacies of the fossil record: as a result, community palmecology has historically developed very slowly. At the community ecosystem level, the need for a theoretical framework is so great that paleoecology must ‘borrow’ the hypotheses of modem ecology. Consideration of the stability-time hypothesis of Sanders in conjunction with the physical setting of transgression and regression has permitted the structuring of three community types and the interpretation of their behavior under variations in the physical environment. These community types (opportunistic. stable mature, relict mature) are recognizable in the fossil record and examples are given from the Upper Pennsylvanian of the Appalachian Basin.

Recent paleoecological studies have emphasized the recognition of successional stages of level-bottom communities, but have neglected to point out techniques for distinguishing succession within a fossil community from the temporal and spatial replacement of one fossil community by another. The physical integrity of a marine level-bottom community is discernible, in most instances, through careful temporal and spatial study, and one community can be distinguished from another by judicious application of the ‘end-member’ concept. Community boundaries are only as distinct as the associated environmental stress gradient. Of first-order significance in understanding fossil community succession and replacement is appreciation of the basic asymmetry of the community dynamics involved in transgression-regression events. Of second-order importance is appreciation of the nature of the onshore-offshore environmental stress gradient, which, in turn, is controlled by the physical setting of transgression-regression (e.g. progradation versus eustatic control; high topographic relief versus low topographic relief, etc.). The application of the preceding concepts is shown by detailed study of community succession and replacement in the Cambridge Limestone (Upper Pennsylvanian), Guernsey County, Ohio.

All of the presently available and processed data from Meadowcroft Rockshelter indicate that the radiocarbon dates for middle and lower Stratum IIa are not discordant with either the associated fauna, flora, and artifacts or with the known geological history of the Cross Creek drainage. Consequently, it is reiterated that the earliest occupations at this locality still represent the best evidence recovered to date for the presence of pre-Clovis or pre-fluted point populations in the New World. It is further suggested that a maintenance of the "Clovis primacy syndrome" is both anachronistic and futile.

The Pliocene to Holocene limestones of Barbuda have formed on a wide, shallow, outlying bank of the Lesser Antilles island arc, some 50 km east of the older axis of the Limestone Caribbees and 100 km east of the newer axis of the active Volcanic Caribbees. Contrasts with neighbouring islands of similar size include the lack of exposed igneous basement or mid-Tertiary sediments, the dominance of younger flat-lying carbonates, and the greater frequency of earthquake shocks. The history of emergence of the island has been studied through aerial reconnaissance, mapping, logging, hand coring, facies and microfacies analysis. These show a pattern of progressively falling high sea level stands (from more than + 50 m down to the present level) on which are superimposed at least three major phases of subaerial exposure, when sea levels were close to, or below, their present level. This sequence can be summarized as follows: 1, bank edge facies (early Pliocene Highlands Formation) deposited at not more than c. 50–100 m above the present sea level; 2, emergence with moderate upwarping in the north, associated with the Bat Hole subaerial phase forming widespread karst; 3, older Pleistocene transgression with fringing reefs and protected bays formed at + l0 to + l5 m high sea level stands (Beazer Formation); 4, Marl Pits subaerial phase with widespread karst and soil formation; 5, late Pleistocene transgression up to +6 m high stand with fringing and barrier reefs, protected backreefs and bays (Codrington Formation Phase I); 6, gradual regression resulting in emergence of reefs, enclosure of lagoons, and progradation of beach ridges at heights falling from c . 5 m to below present sea level (Codrington Phase II); 7, Castle Bay subaerial phase produced karst, caliche and coastal dunes that built eastwards to below present sea level; and 8, Holocene transgression producing the present mosaic, with reefs, lagoons and prograding beach ridge complexes, with the present sea level reached before c . 4085 years BP. The evidence suggests that slight uplift took place in the north of the island after early Pliocene times. Subsequent shoreline fluctuations are consistent with glacio-eustatic changes in sea level, indicating that the island has not experienced significant uplift during the Quaternary.

Excavations in 1980–1981 at sites (32MZ319 and 32MZ380) along Cinnamon Creek Ridge in the Little Missouri River Badlands of McKenzie County, North Dakota, unexpectedly revealed at each locality the presence of one or more deeply buried paleosols with associated cultural materials. At both sites, 32MZ319 and 32MZ380, multiple paleosols are present, each of which is terminated by an episode of aeolian deposition. Fifteen radiocarbon dates on these paleosols establish an incipient chronology for paleosol development in the study area and permit correlation with other High Plains archaeological complexes. Geological and archaeological data for the two multiple paleosol sites are summarized.

Results of a petrographic analysis of inclusions in ceramics have shed new light on the cultural selection and processing of temper in different types of pottery from two Early Bronze Age sites in Jordan: Bab edh-Dhra' and Numeira. Wadi sand was used in fine and common ware bowls, jars, and juglets from EB (Early Bronze Age) I through EB IV times at both sites. Quartz sand, weathered from outcrops of Nubian Sandstone, was used in fine creamware bowls, jars, and platter bowls produced at Numeira during EB III. Larger crushed fragments of limestone were used as temper in cooking pots and coarse hole-mouth jars at Bab edh-Dhra' during EB III and EB IV. Larger fragments of crushed basalt were used for production of bowls and platter bowls of burnished ware during EB III time at both sites. Since the early 1980s, there has been an increasing interaction between archaeology and the physical sciences. In this example, a geological analysis of tempering material has been extremely helpful in supplementin...

An examination of split core photographs from the north-central Pacific reveals the presence of three different burrow morphologies. Simple burrows occur throughout the region. Halo burrows are present in water deeper than 4,000 m (3,000 m along the equator) and removed from continental areas. Imbricate burrows are uncommon and have an irregular distribution. Organisms responsible for the burrows are interpreted as surface to near-surface feeders which do not penetrate deeply into the sediments. Thus, the zone of sediment mixing caused by burrowing ranges from 10 to 30 cm and averages 20 cm.

A laboratory model duplicated the conditions necessary for pisolite formation in mines and caves. These are (1) supersaturated calcium carbonate solution, (2) grain agitation, (3) available nuclei, and (4) the presence of a splash cup. Calcite layers were deposited in the laboratory experiment. Growth rates of pisolites so formed were 1.5-2.5 times greater than the average accretion rate of 0.1-0.2 mm determined from pisolites of known age in mines.

SUMMARYAn electron microscope examination of beach and glacial pebbles suggests that these two environments do not impress distinctively different textures on pebble surfaces. A detailed study of surface textures of beach pebbles indicates that size reduction is predominantly an abrasional rather than solutional process. The three textural features noted, flat planar surfaces, pits and arc-shaped fractures, were characterized by an abundance of mechanical breakage blocks slightly modified by solution. All three textural types were experimentally duplicated.

Quartz sand grains floating in limestone (Cambro-Ordovician and Lower Devonian) were examined by electron microscopy. Four classes of diagenetic surface textures were observed: crystal surfaces, solution surfaces, pressure solution striations, and fracture surfaces. These features result from pore water solution and deposition, and from grain movements during diagenesis.

Two distinctly different mechanisms operate within caves to produce concentrically laminated calcareous oolite, pisolite, and concretion grains. The first, a splash cup occurrence, produces grains under agitated conditions so that both abrasion and carbonate precipitation take place. The second mechanism, the rimstone dam and pool concretion occurrences, produces grains under non-agitated conditions so that carbonate precipitation alone controls grain morphology. The two mechanisms result in laminated grains with distinctively different characteristics. Agitated grains are characterized by distinct, compact laminations which display a pseudo-uniaxial cross caused by an oriented crystal structure. The grains commonly have a nucleus, smooth polished surfaces, a low insoluble residue content, and with continued growth tend to approach a spheroidal shape. In contrast, non-agitated grains generally have indistinct, porous laminations lacking an oriented crystal structure. They commonly lack nuclei, have rough unpolished surfaces, are high in insoluble residue content, and with continued growth develop irregular shapes. The above grain characteristics are applied to more extensive shallow marine deposits. The Bahamian oolite grains show characteristics of agitated grains whereas West Texas Permian Reef pisolite grains are quiescent in character.

More than 4000 quartz sand grain surfaces have been examined by electron micro scopy, and it has been established that specific differences exist depending on the environment of transportation and deposition. Littoral, aeolian, glacial, diagenetic, and combinations of these four environments can be distinguished; river transport and turbidity current movement do not impress characteristic surface textures on quartz sand grains.