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Climatic change appears to influence major patterns in human history. However, confirming the association between climatic events and adaptive human responses is not straightforward given the potential for spurious correlations and uncertainty in the timing of events. Here we leverage theory from behavioral and population ecology to generate predictions about causal relationships between climate and settlement decisions. We then test those predictions using statistical methods designed to evaluate associations under uncertainty. This allows us to evaluate a comprehensive record of radiocarbon dated archaeological sites in the Basin-Plateau region of North America relative to a record of effective precipitation reconstructed using Macrophysical Climate Models. Consistent with theory, the results show that regional populations declined in the mid-Holocene during a prolonged period of reduced precipitation, leading to the abandonment of many major rockshelter sites. Remaining populations concentrated at open-air sites around well-watered sand dune localities where they constructed pithouses and adopted more intensive subsistence practices. These findings illustrate an adaptive response of hunter-gatherer populations to past climate change that supports theoretical predictions and is unlikely to result from spurious correlations or uncertainties in the timing of events. [Display omitted] [ABSTRACT FROM AUTHOR]

Margaret Lyneis examined pottery recovered from two of southern Nevada's desert oases, the Desert National Wildlife Refuge and the Ash Meadows National Wildlife Refuge. People occupied these rich havens of springs and lush vegetation fairly continuously from the Early Archaic period, with farming practiced during the Formative and Post-Formative periods. Lyneis' investigations demonstrated for the first time that pottery was made in these locations during the later periods, with tempers for both gray and brown ware ceramics consisting of crushed rock obtained from adjacent mountains. This paper summarizes these studies and reflects on the implications of Lyneis' research for understanding Nevada's prehistory. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the study was to prospectively establish the use of a novel multidetector computed tomography unit (MDCT) with 320 × 0.5 detector rows for the evaluation of tracheomalacia by using a dynamic expiratory low-dose technique. Methods: Six adult patients (5 men, I woman; mean age, 53.7 years [37-70 years]) referred for a clinical suspicion of tracheomalacia were studied on a 320-row MDCT unit by using the following parameters: 120 kVp, 40-50 mA, 0.5-second gantry rotation, and z-axis coverage of 160 mm sufficient to cover the thoracic trachea to the proximal bronchi. Image acquisition occurred during a forceful exhalation. The image data set was subject to the following analyses: cross-sectional area of airway lumen at 4 predefined locations (thoracic inlet, aortic arch, carina, and bronchus intermedius) and measurement of airway volume. Results: All 6 patients had evidence of tracheomalacia, the proximal trachea collapsed at a later phase of expiration (3-4 seconds) than the distal trachea (2-3 seconds). The most common region of airway collapse occurred at the level of the aortic arch (5/6 [83%]), Three patients (50%) had diffuse segmental luminal narrowing that involved the tracheobronchial tree. The radiation dose (estimated dose length product, computed tomography console) measured 293.9 mGy in 1 subject and 483.5 mGy in 5 patients. Conclusions: Four-dimensional true isophasic and isovolumetric imaging of the central airways by using 320-row MDCT is a viable technique for the diagnosis of tracheomalacia; it provides a comprehensive assessment of airways dynamic. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The Department of Medical Imaging at the University Health Network in Toronto is performing a lung cancer screening study, utilizing low-dose computed tomography (LDCT) as the modality. Baseline and annual repeat results are reported on the first 3352 participants, enrolled between June 2003 and May 2007. Methods: Enrollment was limited to those aged 50 years or older, with a smoking history of at least 10 pack-years, no previous cancer and general good health. A helical low-dose CT (LDCT) of the chest was performed using 120kVp, 40–60mA, images were reconstructed with 1–1.25mm overlapping slices. The primary objectives were the detection of parenchymal nodules and diagnosis of early stage lung cancer. Baseline LDCTs were termed positive if at least one indeterminate non-calcified nodule 5mm or larger in size, or non-solid nodule 8mm or larger in size was identified. Follow up periods for individuals with a positive baseline LDCT were determined by nodule characteristics. Results: The median age at baseline was 60 years (range 50–83), with a median of 30 pack-years of cigarette smoking (range 10–189). Baseline CT evaluations were positive in 600 (18%) participants. To date, 2686 (80%) of the participants have returned for at least one annual repeat screening LDCT. Biopsies have been recommended for 82 participants since the study began, and 64 have been diagnosed with screen-detected cancer (62 lung, two plasmacytoma of the rib). A total of 65 lung cancers have been diagnosed (62 screen-detected, 3 interim), 57 are NSCLC (82% with known stage are stage I or II) and the rate of surgical resection was 80%. Sensitivity and specificity of the protocol in successfully diagnosing early stage lung cancers were 87.7% and 99.3%, respectively. Conclusions: Data indicate that LDCT can identify small lung cancers in an at-risk population. The diagnostic algorithm results in few false-positive invasive procedures. Most cancers are detected at an early stage, where the cancer is resectable with a greater potential for cure. Long-term follow up of lung cancer cases will be carried out to determine survival. [Copyright &y& Elsevier]

Introduction: In 2003, the Department of Medical Imaging at the University Health Network in Toronto, Ontario, became the first Canadian site of the International Early Lung Cancer Action Program (I-ELCAP). We report the results from the first 1000 baseline studies. Methods: Between June 2003 and December 2005, we enrolled 1000 high-risk smokers (that is, smokers with a history of at least 10 pack years, or the equivalent of one pack daily for 10 years), aged 55 years or older. A low-dose helical computed tomography (CT) (40 to 60 mA, 120 kV) was performed with 1.0 to 1.25 mm collimation. Nodules found at baseline were followed according to the I-ELCAP protocol: 1) no noncalcified nodules (NCNs) or NCNs ≤ 4 mm or nonsolid nodules < 8 mm, annual repeat; 2) NCNs ≥ 5 mm or nonsolid nodules < 8 mm, 3-month follow-up; or 3) nonsolid nodules ≥ 15 mm, antibiotics and 1-month follow-up. Results: The first 1000 study participants were aged 63 years, standard deviation (SD) 6 years, with a smoking history of 38 pack years, SD 22 pack years; 662 (66%) were former smokers, and 338 (34%) were current smokers; 453 (45%) were men, and 547 (55%) were women. Of the participants, 256 (26%) had a positive baseline low-dose computed tomography (LDCT) scan; 227 (23%) were followed after 3 months and 16 (1.6%) after 1 month; 7 (0.7%) received a contrast-enhanced CT and 6 (0.6%) an immediate CT-guided biopsy. Twenty-six invasive procedures were performed: 22 CT-guided biopsies, 1 ultrasound-guided lymph node metastasis biopsy, 1 bronchoscopic biopsy, and 2 surgeries. The malignancy rate of the invasive procedures was 85%. Overall, the malignancy prevalence is 2.2%. Of the malignancies, 20 are lung carcinomas: 19 non-small-cell lung carcinomas (NSCLCs) (14 adenocarcinoma or bronchioalveolar carcinoma [BAC], 4 squamous carcinoma, and 1 large-cell carcinoma) and 1 small-cell carcinoma; 15 (78%) of the NSCLCs are Stage I. Fourteen patients underwent surgery (1 pneumonectomy, 9 lobectomies, and 4 segmentectomies). Conclusion: Our results confirm that LDCT identifies small, early-stage, resectable lung cancer in a high-risk population. [ABSTRACT FROM AUTHOR]

Abstract: Multi-detector CT scanners facilitate the detection of very small nodules within the lung parenchyma, with a sensitivity that is significantly superior to that of chest radiography. It has been demonstrated that an unacceptable number of nodules may be missed by radiologist reading. The issues of reader fatigue and the presentation of essentially redundant image appearances are addressed with the development of semi-automated computer-aided detection (CAD) software algorithms. The purpose of this study is to assess one of the commercially available tools, the ImageChecker-CT, from R2 Technology, within a state-of-the art screening study. [Copyright &y& Elsevier]

Some 40 years after the field of cultural resource management was conceived, the most surprising consequence may be that the sheer quantity of archaeological observations made by the field's practitioners has far outstripped our ability to synthesize information and make those synthetic studies available to key interests, including government archaeologists, cultural resource management professionals, and the academy. Here we revisit the key proposals put forward in Bill Lipe's Conservation Model for American Archaeology, published in Kiva in 1974, to provide context for understanding the present and the future of cultural resource management and archaeological research. We see today's "conservation crisis" as a crisis in data management and call for a fundamental transformation in how we think about archaeological data and how we educate and train archaeologists in order to secure a productive future for cultural resource management and for the field of archaeology as it is practiced in North America. [ABSTRACT FROM AUTHOR]

Computer-aided detection (CAD) has been shown to increase the sensitivity for detection of pulmonary nodules in adults. This study reports initial findings utilizing a CAD system for the detection of pediatric pulmonary nodules. To assess the performance of CAD and pediatric radiologists in the detection of pediatric pulmonary nodules. CT scans from a series of pediatric patients with known primary tumors and lung nodules were analyzed by four radiologists and a commercially available CAD system. IRB approval was obtained. Sensitivities were calculated for detection according to nodule size and location. In 24 children (age 3–18 years) 173 nodules were identified. Overall the sensitivity of CAD was 34%, but the sensitivity of CAD for detection of nodules 4.0 mm or larger was 80%. Overall radiologist sensitivity ranged from 68% to 79%. There were 0.9 CAD false-positives and 0.3–2.4 radiologist false-positives per study. CAD in our pediatric oncology patients had good sensitivity for detection of lung nodules 4 mm and larger with a low number of false-positives. However, the sensitivity was considerably less for nodules smaller than 4 mm. [ABSTRACT FROM AUTHOR]

Purpose Radiographic changes after lung stereotactic body radiation therapy (SBRT) have been categorized into 4 groups: modified conventional pattern (A), mass-like fibrosis; (B), scar-like fibrosis (C), and no evidence of increased density (D). The purpose of this study was to assess the interrater reliability of this categorization system in patients with early-stage non-small cell lung cancer (NSCLC). Methods and Materials Seventy-seven patients were included in this study, all treated with SBRT for early-stage (T1/2) NSCLC at a single institution, with a minimum follow-up of 6 months. Six experienced clinicians familiar with post-SBRT radiographic changes scored the serial posttreatment CT images independently in a blinded fashion. The proportion of patients categorized as A, B, C, or D at each interval was determined. Krippendorff's alpha (KA), Multirater kappa (M-kappa), and Gwet's AC1 (AC1) scores were used to establish interrater reliability. A leave-one-out analysis was performed to demonstrate the variability among raters. Interrater agreement of the first and last 20 patients scored was calculated to explore whether a training effect existed. Results The number of ratings ranged from 450 at 6 months to 84 at 48 months of follow-up. The proportion of patients in each category was as follows: A, 45%; B, 16%; C, 13%; and D, 26%. KA and M-kappa ranged from 0.17 to 0.34. AC1 measure range was 0.22 to 0.48. KA increased from 0.24 to 0.36 at 12 months with training. The percent agreement for pattern A peaked at 12 month with a 54% chance of having >50% raters in agreement and decreased over time, whereas that for patterns B and C increased over time to a maximum of 20% and 22%, respectively. Conclusion This post-SBRT radiographic change categorization system has modest interrater agreement, and there is a suggestion of a training effect. Patterns of fibrosis evolve after SBRT and alternative categorization systems should be evaluated. [ABSTRACT FROM AUTHOR]

Despite the positive outcome of the recent randomized trial of computed tomography (CT) screening for lung cancer, substantial implementation challenges remain, including the clear reporting of relative risk and suggested workup of screen-detected nodules. Based on current literature, we propose a 6-level Lung-Reporting and Data System (LU-RADS) that classifies screening CTs by the nodule with the highest malignancy risk. As the LU-RADS level increases, the risk of malignancy increases. The LU-RADS level is linked directly to suggested follow-up pathways. Compared with current narrative reporting, this structure should improve communication with patients and clinicians, and provide a data collection framework to facilitate screening program evaluation and radiologist training. In overview, category 1 includes CTs with no nodules and returns the subject to routine screening. Category 2 scans harbor minimal risk, including <5 mm, perifissural, or long-term stable nodules that require no further workup before the next routine screening CT. Category 3 scans contain indeterminate nodules and require CT follow up with the interval dependent on nodule size (small [5-9 mm] or large [≥ 10 mm] and possibly transient). Category 4 scans are suspicious and are subdivided into 4A, low risk of malignancy; 4B, likely low-grade adenocarcinoma; and 4C, likely malignant. The 4B and 4C nodules have a high likelihood of neoplasm simply based on screening CT features, even if positron emission tomography, needle biopsy, and/or bronchoscopy are negative. Category 5 nodules demonstrate frankly malignant behavior on screening CT, and category 6 scans contain tissue-proven malignancies. [ABSTRACT FROM AUTHOR]

Abstract: Thousands of turquoise artifacts have been recovered from archaeological sites in Chaco Canyon and other Ancestral Puebloan (formerly known as the Anasazi) sites across the San Juan Basin in northwestern New Mexico suggesting that turquoise was an important commodity in these ancient trade networks. Although the well documented group of turquoise deposits in the Cerrillos Hill have been the main contender for the geological source of Chacoan turquoise because they are the closest in proximity to the canyon, recent studies show that turquoise was obtained through long-distance trade networks that extended hundreds of kilometers to the west. To investigate Ancestral Puebloan turquoise procurement strategies and trade networks, we analyzed 74 turquoise artifacts from Puebloan sites in the San Juan Basin and the Virgin Puebloan area in southern Utah and the Moapa Valley in Nevada by a technique we developed that identifies the geological source of turquoise artifacts using the isotope ratios of hydrogen and copper and a comparative database that contains the isotope fingerprints of 22 turquoise resource areas. Here we present geochemical evidence of multiple turquoise trade routes into Chaco Canyon linking turquoise from the San Juan Basin with deposits along the Rio Grande Rift and resource areas in Nevada and the Mojave region of southeastern California. By linking Chacoan turquoise with the western turquoise resource areas, our data supports the proposal that the Virgin Puebloan may have played an important role in the movement of turquoise, shell, and salt to the San Juan Basin. Our turquoise sourcing technique establishes the foundation for future turquoise provenance studies in additional regions beyond the American Southwest including Mexico, South America, China, and Persia. The use of isotope ratios should be tested as unique discriminators for other complex minerals. [Copyright &y& Elsevier]

Brahma ( BRM) has a key function in chromatin remodeling. Two germline BRM promoter insertion-deletion polymorphisms, BRM-741 and BRM-1321, have been previously associated with an increased risk of lung cancer in smokers and head and neck cancer. To further evaluate their role in cancer susceptibility particularly in early disease, we conducted a preplanned case-control study to investigate the association between the BRM promoter variants and stage I/II upper aerodigestive tract ( UADT) cancers (i.e., lung, esophageal, head and neck), a group of early-stage malignancies in which molecular and genetic etiologic factors are poorly understood. The effects of various clinical factors on this association were also studied. We analyzed 562 cases of early-stage UADT cancers and 993 matched healthy controls. The double homozygous BRM promoter variants were associated with a significantly increased risk of early stage UADT cancers (adjusted odds ratio [ aOR], 2.46; 95% confidence interval [ CI], 1.7-3.8). This association was observed in lung ( aOR, 2.61; 95% CI, 1.5-4.9) and head and neck ( aOR, 2.75; 95% CI, 1.4-5.6) cancers, but not significantly in esophageal cancer ( aOR, 1.66; 95% CI, 0.7-5.8). There was a nonsignificant trend for increased risk in the heterozygotes or single homozygotes. The relationship between the BRM polymorphisms and early-stage UADT cancers was independent of age, sex, smoking status, histology, and clinical stage. These findings suggest that the BRM promoter double insertion homozygotes may be associated with an increased risk of early-stage UADT cancers independent of smoking status and histology, which must be further validated in other populations. [ABSTRACT FROM AUTHOR]

The article discusses a study to determine factors responsible for presuming the probability of cancer in pulmonary nodule diagnosed on the first screening computed tomography (CT) scan. The study found prognosis of cancer in the older age, family history of lung cancer and in the case of emphysema. It suggests that predictive tools based on patient and nodule characteristics could be used to determine the probability of cancer in pulmonary nodule.

The SWI/SNF chromatin remodeling complex is an important regulator of gene expression that has been linked to cancer development. Expression of Brahma (BRM), a critical catalytic subunit of SWI/SNF, is lost in a variety of solid tumors. Two novel BRM promoter polymorphisms (BRM-741 and BRM-1321) have been correlated with BRM loss and elevated cancer risk. The aim(s) of this study were to examine BRM expression in head and neck squamous cell carcinoma (HNSCC) and to correlate BRM polymorphisms with HNSCC risk. BRM expression studies were performed on eight HNSCC cell lines and 76 surgically resected tumor samples. A case–control study was conducted on 668 HNSCC patients (oral cavity, oropharynx, larynx and hypopharynx) and 700 healthy matched controls. BRM expression was lost in 25% of cell lines and 16% of tumors. The homozygous genotype of each polymorphism was significantly associated with increased HNSCC risk [BRM-741: adjusted odds ratio (aOR) 1.75, 95% CI 1.2–2.3, P < 0.001; BRM-1321: aOR 1.65, 95% CI 1.2–2.2, P < 0.001]. Individuals that were homozygous for both BRM polymorphisms had a more than 2-fold increase in the risk of HNSCC (aOR 2.23, 95% CI 1.5–3.4, P < 0.001). A particularly elevated risk was seen within the oropharynx, human papillomavirus-positive subgroup for carriers of both homozygous variants (aOR 3.09, 95% CI 1.5–6.8, P = 0.004). BRM promoter polymorphisms appear to act as susceptibility markers of HNSCC with potential utility in screening, prevention and treatment. [ABSTRACT FROM AUTHOR]

Background: Bronchiolitis obliterans syndrome (BOS) with small-airway pathology and obstructive pulmonary physiology may not be the only form of chronic lung allograft dysfunction (CLAD) after lung transplantation. Characteristics of a form of CLAD consisting of restrictive functional changes involving peripheral lung pathology were investigated. Methods: Patients who received bilateral lung transplantation from 1996 to 2009 were retrospectively analyzed. Baseline pulmonary function was taken as the time of peak forced expiratory volume in 1 second (FEV1). CLAD was defined as irreversible decline in FEV1 < 80% baseline. The most accurate threshold to predict irreversible decline in total lung capacity and thus restrictive functional change was at 90% baseline. Restrictive allograft syndrome (RAS) was defined as CLAD meeting this threshold. BOS was defined as CLAD without RAS. To estimate the effect on survival, Cox proportional hazards models and Kaplan-Meier analyses were used. Results: Among 468 patients, CLAD developed in 156; of those, 47 (30%) showed the RAS phenotype. Compared with the 109 BOS patients, RAS patients showed significant computed tomography findings of interstitial lung disease (p < 0.0001). Prevalence of RAS was approximately 25% to 35% of all CLAD over time. Patient survival of RAS was significantly worse than BOS after CLAD onset (median survival, 541 vs 1,421 days; p = 0.0003). The RAS phenotype was the most significant risk factor of death among other variables after CLAD onset (hazard ratio, 1.60; confidential interval, 1.23–2.07). Conclusions: RAS is a novel form of CLAD that exhibits characteristics of peripheral lung fibrosis and significantly affects survival of lung transplant patients. [Copyright &y& Elsevier]

Purpose: To assess the prevalence and nature of incidental findings (IF) seen in low-dose computed tomographies (LDCT) from a lung cancer screening study for at-risk individuals. Materials and Methods: Radiology reports from LDCTs of 4073 participants of a lung cancer screening study were retrospectively reviewed for findings other than lung nodules, that is, IFs, which were regarded as actionable. The frequency, nature, and expected cost of these IFs, and their anticipated follow-up were estimated. Results: There were 880 IFs described in 782 study participants (19%); the median age of the participants was 62 years (range, 46-80 years). More IFs were found in men (55%) than in women. The majority of these findings were noncardiovascular (76%), for which imaging was suggested for 74%. There were 7 severe IFs (0.8%) that merited immediate attention. Seven known cancers were diagnosed from follow-ups of the IFs. The majority of IFs (n = 486 [55%]) would require imaging follow-up if clinically indicated, with an estimated total a cost of CAN$45,500 to CAN$51,000 to provide initial diagnostic workup. Conclusion: IFs on lung cancer screening studies are not uncommon and frequently require imaging or other follow-up for definitive diagnoses and to assess their clinical relevance. The implication of IFs has to be considered when determining a cost-effective and ethical protocol for the utilisation of LDCT in a high-risk population. [ABSTRACT FROM AUTHOR]

Although support groups are widely available on the Internet, little is known about the conversations in them. We hypothesized that automatic text analysis may be a powerful tool helping to understand what is communicated in these groups. In an exploratory study, the postings of nine women participating in a semi-structured breast cancer support group program were analyzed with a human rater and with Pennebaker and Francis'' text analysis software (LIWC). The computer scores on most of the selected word categories and human ratings were moderately correlated. This indicates concurrent validity of the LIWC. An indication for construct validity was found by comparing the LIWC scores of the on-line group with those of other texts. Automated text analysis should be further developed for on-line discussions where they may serve as a useful tool for group moderators and researchers. [Copyright &y& Elsevier]