Frequency Distribution Map Research Articles

Lesion Frequency Distribution Maps of Traumatic Axonal Injury on Early Magnetic Resonance Imaging After Moderate and Severe Traumatic Brain Injury and Associations to 12 Months Outcome.

Traumatic axonal injury (TAI) is a common finding on magnetic resonance imaging (MRI) in patients with moderate-severe traumatic brain injury (TBI), and the burden of TAI is associated with outcome in this patient group. Lesion mapping offers a way to combine imaging findings from numerous individual patients into common lesion maps where the findings from a whole patient cohort can be assessed. The aim of this study was to evaluate the spatial distribution of TAI lesions on different MRI sequences and its associations to outcome with use of lesion mapping. Included prospectively were 269 patients (8-70 years) with moderate or severe TBI and MRI within six weeks after injury. The TAI lesions were evaluated and manually segmented on fluid-attenuated inversed recovery (FLAIR), diffusion weighted imaging (DWI), and either T2* gradient echo (T2*GRE) or susceptibility weighted imaging (SWI). The segmentations were registered to the Montreal Neurological Institute space and combined to lesion frequency distribution maps. Outcome was assessed with Glasgow Outcome Scale Extended (GOSE) score at 12 months. The frequency and distribution of TAI was assessed qualitatively by visual reading. Univariable associations to outcome were assessed qualitatively by visual reading and also quantitatively with use of voxel-based lesion-symptom mapping (VLSM). The highest frequency of TAI was found in the posterior half of corpus callosum. The frequency of TAI was higher in the frontal and temporal lobes than in the parietal and occipital lobes, and in the upper parts of the brainstem than in the lower. At the group level, all voxels in mesencephalon had TAI on FLAIR. The patients with poorest outcome (GOSE scores ≤4) had higher frequencies of TAI. On VLSM, poor outcome was associated with TAI lesions bilaterally in the splenium, the right side of tectum, tegmental mesencephalon, and pons. In conclusion, we found higher frequency of TAI in posterior corpus callosum, and TAI in splenium, mesencephalon, and pons were associated with poor outcome. If lesion frequency distribution maps containing outcome information based on imaging findings from numerous patients in the future can be compared with the imaging findings from individual patients, it would offer a new tool in the clinical workup and outcome prediction of the patient with TBI.

A repertoire of single nucleotide polymorphisms (SNPs) of major fecundity BMPR1B gene among 75 sheep breeds worldwide

The BMPR1B gene is a major determinant of sheep reproductive capacity. Previous studies revealed that Q249R (FecB) is a profound variant of BMPR1B that influences the ovulation rate and litter size in sheep. However, unlike Q249R locus, the full spectrum of single nucleotide polymorphisms (SNPs) within BMPR1B has not been extensively studied. A systematic screen of SNPs in BMPR1B would facilitate the discovery of novel variants that are associated with litter size. This study aimed to investigate SNPs in the BMPR1B gene via whole genome sequence (WGS) data from 2409 individuals of 75 sheep breeds worldwide. Herein, a total of 9688 variants were screened, among which 15 were coding variants and 8 were novel changes. Specifically, we presented the most comprehensive frequency distribution map of the well-known FecB mutation to date. Besides, among the above-mentioned SNPs, one synonymous mutation (g.30050773C > T) was found to be likely under selection and is potentially associated with fecundity in Duolang sheep. Thus, our study greatly expands the variation repertoire of the ovine BMPR1B gene and provides a valuable resource for exploring causative mutations and genetic markers associated with litter size.

Phenotypic Diversity and Relationships of Fruit Traits in Persimmon (Diospyros kaki Thunb.) Germplasm Resources

Persimmons (Diospyros kaki Thunb.) are a characteristic Chinese fruit and account for a large planting area in China. The evaluation and selection of persimmons that are astringent without softening play an important role in modern breeding programs. However, the phenotypic variability and diversity of some representative traits in the natural population of persimmon germplasm without softening are still unclear. In this study, 56 traits from 150 samples of D. kaki collected in East Asia were used to evaluate phenotypes and correlations using principal component analysis (PCA) and cluster analysis. The results show that the mean coefficient of variation for the persimmon germplasm traits was 26.19%, and significant variations in phenotypic traits were observed. The frequency distribution maps of most of the characteristics showed obvious normal distribution characteristics. The analysis of the correlations between the traits showed that the most significant positive correlations had correlation coefficients close to 0.7. For example, seed width was highly and significantly correlated with fruit longitudinal and transverse width (0.796 and 0.786), and pith height was highly and significantly correlated with seed length (0.816). Moreover, the correlations between fruit traits and support traits, such as those related to the fruit handle and sepals, were significant, and the coefficients of the correlations between sepal width and fruit traits were 0.671 to 0.739. Fruit water content was negatively correlated with the soluble solids content (−0.623). Principal component analysis reduced 38 traits to 8 principal components, explaining 82.459% of the total variations, which were related to fruit size, seed, pith, color, fruit hardness, and soluble solid content; thus, persimmon germplasm could be divided into three major categories according to the sizes and shapes of the traits, and the first cluster was divided into two subcategories. The first subclass of fruits is medium size and shape; the second subclass of fruits is small in all traits; the second cluster is of high-quality and large fruits, optimal in all traits; and the third cluster is of medium to high-quality and oblate fruits. The results of this study are important for genetic improvement, diversity conservation, and resource utilization regarding persimmons and further research in this regard.

Composition Analysis and Category Prediction Model of Ancient Glass Based on Decision Tree

Ancient glass is easily affected by environmental factors, which cause chemical changes between glass composition and environmental substances and leads to weathering. It is important to analyze the chemical composition of ancient glass for the study of the Silk Road. To study the composition of glass cultural relics, the relationship between surface weathering and glass type, ornamentation and colour was analyzed first, and then qualitative analysis was carried out through a frequency distribution map, and grouping was carried out according to glass type and surface weathering type, the statistical distribution law of each chemical composition was studied, and the loss of chemical composition with or without weathering was analyzed; Finally, the chemical composition content of the weathered sample before weathering is predicted according to the chemical composition ratio of the weathered and non-weathered cultural relics. The experimental results show that the model has good robustness and can be used to prepare and quickly predict the composition and classification of ancient glasses.

Radar Deception Jamming Recognition Based on Weighted Ensemble CNN With Transfer Learning

With the development of new active deception jamming, radar antijamming has become a major research hotspot, and the recognition of jamming type is one of its key steps. In recent years, deep learning has been successfully applied in the field of radar jamming recognition, such as convolutional neural networks (CNNs). However, it is difficult to effectively improve the accuracy of deep learning algorithms in the case of small sample. Furthermore, ensemble learning and transfer learning can effectively improve the model generalization performance. For the small sample problem, this article proposes a weighted ensemble CNN with transfer learning (WECNN-TL)-based radar active deception jamming recognition algorithm. The main idea of this method is to obtain the time–frequency distribution maps of jamming signals by the short-time Fourier transform (STFT), and then, their real parts, imaginary parts, moduli, and phases are combined differently to construct multiple datasets. Finally, an ensemble CNN (ECNN) model with weighted voting and transfer learning is constructed to realize jamming recognition. Experiments on the simulated and measured mixed datasets (including 12 types of samples) show that the proposed method can get better recognition performance than random forest (RF), support vector machine (SVM), and some CNN-based methods.

Vibration characteristics of the gear shaft-bearing system with compound defects under variable operating conditions

Due to the variable working conditions, there are compound defects in the gear shaft-bearing system easily, vibration signals are very complex, and the fault diagnosis of the system becomes more difficult. Thus, a 36 degrees of freedom (36-DOFs) dynamic model is established for discussing the vibration characteristics of the gear shaft-bearing system, the gear pair spalling defect is considered, there are localized defects on the inner raceway and outer raceway of the supporting bearing, the work conditions contain variable speed, variable load, speed fluctuation, and load fluctuation. The obtained vibration signal is processed by the short-time Fourier transform for the time–frequency distribution map. When the gear shaft-bearing system with compound defects operates under variable conditions, roller passing outer raceway frequency, roller passing inner raceway frequency, gearing meshing frequency, and the relative harmonic frequencies can also be found. The defect frequencies and frequency amplitude are increasing with the speed while the system makes the accelerated movement. While the load acting on the system increases, the defect frequencies remain unchanged, but the frequency amplitude becomes larger. If there are fluctuations of the speed and load, the apparent defect frequency fluctuation and amplitude fluctuation is generated. The mathematical model and the analysis results are verified by the experiment, which will provide the theoretical basis for the fault diagnosis of the gear shaft-bearing system.

Distribution of isonymy index in the territory of Ukraine

Purpose of the study: to calculate the irrationality index Ir for the population of the region level, to analyze the regularity of distribution of its values in the territories of Ukraine, which differ in geographical conditions and previous history of population formation. Methods. Using total names, isonymy indices for the entire population of Ukraine, individual regions and oblasts are calculated. Results. The Ir index for the whole population of Ukraine is 2,13×10-4. In some regions of Ukraine it has the following meanings: east – 2,69×10-4, south - 2,23×10-4, center - 3,15×10-4, north - 3,40×10-4, west – 2,40×10-4. The Ir frequency distribution map for regional populations shows a gradient of this index rising from the southeast to the northwest of the country. The minimum Ir value is observed in the Crimea (1,61×10-4), the maximum in the Volyn region (7,14×10-4). Conclusions. The Ukrainian population isonymy index is of the same order of magnitude as in other European countries. The territorially dependent variation of the isonymy index is explained in the peculiarities of the history and landscape of the area.
 Keywords: population, isonymy, surnames, migration, genetic drift.

ASSESSMENT OF EARLY SEASON AGRICULTURAL DROUGHT USING REMOTE SENSING

Abstract. Drought is a stochastic natural hazard that is caused by intense and persistent shortage of precipitation. The initial shortage of rainfall subsequently impacts the agriculture and hydrology sectors. Marathwada region of India comes under highly drought prone area in the country. Recent times have shown the increase in occurrence of agricultural drought in the non-monsoon season. The deviation from normal rainfall in the month of October causes soil moisture deficit which triggers an agricultural drought in the early-Rabi season. The traditional remote sensing based agricultural drought monitoring indices lack in identifying the early-season (ES) drought. An attempt has been made in the present study, to map ES agricultural drought in the Aurangabad district of Marathwada region using remote sensing. The meteorological deficit in the month of October, has been assessed using Standardized Precipitation Index (SPI). Impact of meteorological fluctuations on agricultural system in terms of dryness/wetness was evaluated using the Shortwave Angel Slope Index (SASI) derived using MODIS (Terra) Level-3, 8 daily, surface reflectance data for the October months of 2001–2012. It was observed that the area experiences moderate to severe drought 5 times with 12 years of study period (2001–2012). SASI and its parameters were estimated for each week of October month. SASI maps were further classified in four categories viz. moist vegetation; dry vegetation; moist soil and dry soil. The detailed analyses if these maps indicate that agricultural stress occurs in this area even if there is no meteorological stress. However, whenever, there is meteorological stress the area under agricultural stress exceeds more than 50% of the study region. A frequency distribution map of ES drought was prepared to identify the most drought prone area of the district and to alternately identify the irrigated area of the district.

Study of the Tensile Damage of 321 Stainless Steel for Solar Thermal Power Generation by Acoustic Emission

In this paper, the acoustic emission technique was used to study the signal during the tensile damage of 321 stainless steel for solar thermal power generation. It was found that the peak frequency can effectively distinguish different types of signals during the tensile test. The interference signals generated during the tensile test are effectively resolved by combining the amplitude-peak frequency distribution map and the energy-peak frequency distribution map. The amplitude-time map of the acoustic emission signal is successfully divided into three stages by using peak frequency parameter.

Parameter Estimation of Multi Frequency Hopping Signals Based on Space-Time-Frequency Distribution

Frequency hopping spread spectrum (FHSS) communication is widely used in military and civil communication, and the parameter estimation of frequency hopping (HF) signals is of great significance. In order to estimate the parameters of multiple frequency hopping signals effectively, a blind parameter estimation algorithm based on space-time frequency analysis (STFA) and matrix joint diagonalization (JDM) is proposed. Firstly, the time domain signal received by the linear array is converted to the space-time frequency domain through the space-time frequency transformation, and the space-time frequency distribution (STFD) of the signal is obtained. Then the time-frequency point is extracted from the space-time frequency distribution map, the extraction of the hop is completed by the method of finding an “island”, and the space-time frequency matrix of each hop is constructed, and then the preliminary estimation of each jump frequency, jump time and jump period is completed. Finally, the space-time-frequency matrix of the same hop received by different array elements is jointly diagonalized by the matrix joint diagonalization algorithm, and the diagonalization matrix is obtained. On the basis of the diagonalization matrix, the root-MUSIC algorithm is used to complete the direction of arrival (DOA) estimation of the frequency hopping signal and the separation of the frequency hopping radio. The simulation results show that the proposed algorithm is effective in parameter estimation of multi-hopping signals. It can estimate the parameters of −4 dB signal-to-noise ratio (SNR). The accuracy rate of parameter (hop period, DOA, hop start time, hop end time, frequency hopping frequency set) estimation reaches 73.26%, and the sparse linear regression (SLR) algorithm reaches 70.15%. When the signal-to-noise ratio reaches 5 dB, the accuracy of estimation can reach 94.74%, and the SLR reach 85.64%. It has a good effect on parameter estimation of multi-hopping signals.

Estimation of the Site Effect Using Microtremor Technique at New Akhmim City, Akhmim, Sohag, Egypt

Abstract —Local site effect is a significant aspect of seismic hazards, which often causes amplification of ground motions and results in increase in the damage potential of an earthquake. This article displays an experimental study of microtremors data to investigate the dynamic characteristics of the soil and structures in the desert zone of Akhmim City, east of River Nile, Sohag governorate, Egypt. Because of progressive population growth in the Nile valley and delta regions, the Egyptian Governorate considered increasing the number of new communities, especially in the Sohag district, to improve the living conditions. The study area is one of the new urban areas which was suggested by Egyptian Urban Communities Authority (EUCA). For this purpose, the horizontal to vertical (H/V) spectral ratio was used to provide precious information about the soil properties and its engineering features for foundation purposes. The H/V spectral ratio analyses of ambient noise data at the measurement stations were processed and interpreted using Geopsy Software to calculate the amplification factor and fundamental resonance frequency at each observation point. The results indicate that the resonance frequency ranges between 0.21 and 0.28 Hz at the most of the measurement stations, with some irregularities at stations No. 2 and 4 because of the higher softness of sediments in these locations. Most of lower fundamental frequencies are observed in the southern part of the study area, whereas higher values are observed in the northern part of the study area. The amplification factor ranges between 1.38 and 4.15. Higher values were recorded in the northeastern and southern parts, while lower ones were observed in the northwestern and southwestern parts of the mapped area. It can be concluded that the amplification component increases with increasing softness of the sediments. Interpretation of fundamental frequency distribution map is very significant to estimate the building heights and the number of stories, which was estimated to be 35 to 47.

Comparison of relative and absolute values of magnetic resonance imaging in the diagnosis of spinal epidural lipomatosis

ObjectiveTo describe spinal epidural lipomatosis (SEL) of the lumbar region and evaluate the relative versus absolute values of epidural fat (EF) to determine which is more appropriate when using magnetic resonance imaging (MRI).DesignComparative study.SettingHospital.ParticipantsEight SEL patients and 40 healthy adults.InterventionsMRI measurement of EF.Outcome MeasuresThe MRI-based EF thickness, cutoff value, and coefficient of variation (CV) were calculated. Frequency distribution maps for the absolute EF value and the relative EF/DuS value were created.ResultsSEL involved L3 − L4 in all cases. The mean EF thickness was 12.11 ± 2.28 mm (range: 9.91 − 16.86 mm), and the average diameter of the dural sac (DuS) was 20.02 ± 2.64 mm; the EF/DuS ratio was 0.61 ± 0.03. In controls, the average EF thickness was 7.35 ± 1.68 mm (range: 4.81 − 10.92 mm), and the average DuS was 20.86 ± 2.11 mm; the EF/DuS ratio was 0.35 ± 0.08. The relative and absolute values were significantly higher in the SEL group than in the normal group. A cutoff value of 9.8 mm could distinguish SEL patients from normal individuals. For the SEL group, the CV of the relative values (4.9%) was lower than that of the absolute values (18.8%). The frequency distribution map showed that the distribution of relative values was more concentrated than that of the absolute values for both groups.ConclusionBased on the frequency distribution and CVs, the relative value of EF/DuS maybe a better measure for diagnosing SEL than the absolute EF value.

Osteochondrosis, Synovial Fossae, and Articular Indentations in the Talus and Distal Tibia of Growing Domestic Pigs and Wild Boars.

Articular osteochondrosis (OC) often develops in typical locations within joints, and the characterization of OC distribution in the pig tarsus is incomplete. Prevalence of OC is high in domestic pigs but is presumed to be low in wild boars. Postmortem and computed tomography (CT) examinations of the talus and distal tibia from 40 domestic pigs and 39 wild boars were evaluated for the locations and frequencies of OC, synovial fossae, and other articular indentations, and frequency distribution maps were made. All domestic pigs but only 5 wild boars (13%) had OC on the talus. In domestic pigs, OC consistently affected the axial aspect of the medial trochlea tali in 11 (28%) joints and the distomedial talus in 26 (65%) joints. In wild boars, all OC lesions consistently affected the distomedial talus. On the articular surface of the distal tibia, all domestic pigs and 34 wild boars (87%) had synovial fossae and 7 domestic pigs (18%) had superficial cartilage fibrillation opposite an OC lesion (kissing lesion). Other articular indentations occurred in the intertrochlear groove of the talus in all domestic pigs and 13 wild boars (33%) and were less common on the trochlea tali. The prevalence of tarsal OC in wild boars is low. In domestic pigs and wild boars, OC is typically localized to the distomedial talus and in domestic pigs also to the medial trochlea tali. Further investigations into the reasons for the low OC prevalence in wild boars may help in developing strategies to reduce OC incidence in domestic pigs.

119 野球のバッティングにおける左右への打ち分けを可能にするバット角度(打撃動作分析)

In baseball batting, the horizontal direction to which the batted ball will project is influenced by two factors; (a) the direction to which the impacting surface of the bat is facing at ball impact and (b) the interaction of the inclination angle of the bat in the vertical direction and the position of the ball impact along the short axis of the bat. The purpose of this study was to describe the three-dimensional orientation of baseball bat at ball impact for each direction (same, center, and opposite field) of batted ball. Forty-seven elite baseball players performed 7-36 trials of free-batting. Behavior of the ball impact was recorded with two high-speed cameras (2500 fps). All trials in which the bat collided with the ball, including the foul balls, were used for the analysis. The orientation of bat at ball impact was described as the azimuth angle and the depression angle of the bat's long-axis. Frequency distribution maps were constructed to display the probability of hitting the ball toward the same, center and opposite fields for each combination of azimuth and depression angles of the bat at ball impact. The frequency distribution maps illustrate that a unique zone exists for each direction of the batted ball and that the zones overlap substantially. These results suggest that batters can hit the ball toward the three directions even if the orientation of bat at ball impact was same.

Effects of Land Surface Temperature on the Frequency of Convective Precipitation in the Tokyo Area

This study uses statistical evaluation by correlation analysis to examine the effects of thermal environment on the frequency of convective precipitation in the Greater Tokyo Area between 12:00 and 18:00 on summer days from 1997 to 2006. To extract the frequency of convective precipitation we used Automated Meteorological Data Acquisition System radar data to obtain detailed rainfall distribution maps, and to extract the urban thermal environment we used surface temperature data from a National Oceanic and Atmospheric Administration weather satellite. Results were a coefficient of determination of 0.01, indicating no clear relation between surface temperature and convective rain frequency in the study area. Examining the convective rain frequency distribution map in conjunction with an elevation map of the area indicates that higher elevation is a better predictor of increased frequency of convective rainfall than is surface temperature. Because this indicates that orographic precipitation has a large influence in the study area, we used an elevation map to exclude hilly and mountainous regions, regions bordering flat areas (under the assumption that wind could easily move orographic precipitation to such areas), and regions containing marine areas. Doing so resulted in a coefficient of determination of 0.38, a clear signal that differences in the thermal environment in the Greater Tokyo Area have an effect on the frequency of convective precipitation. We next focused on metropolitan Tokyo, the most developed part of the region and the part experiencing the most frequent occurrences of convective precipitation, and we performed correlation analysis considering parameters related to buildings. Results indicate that orographic precipitation has a strong influence in metropolitan Tokyo as well, so we excluded those areas that were excluded from the Greater Tokyo Area analysis and again performed correlation analysis. However, we found no clear relation of convective precipitation frequency with surface temperature or building parameters.

Age-related Changes of Body Composition Structure Based on Differences in Morphological Qualities of Japanese Preschool Children

This study aims to clarify age-related changes of body composition structure in terms of the percentages of body fat and muscle (muscle mass/weight×100) in preschool children by using BMI. The subjects were 533 preschool children, comprising 260 boys and 273 girls. Regression analysis for BMI was performed and a regression polynomial of a proper order was determined. After examining the validity of the order in a regression polynomial for %Fat and muscle percentages for BMI, a regression polynomial evaluation chart was made up. After judging the degree of fat or muscle accumulation from BMI and the fat or muscle percentages for each age group of the boys and girls, a frequency distribution map of excessive development and underdevelopment of fat and muscle was drawn up and its age-related changes were examined. As a result, a complementary relationship was confirmed to exist between BMI and %Fat in preschool children. In contrast, an opposite relationship was found for BMI and muscle percentages. These results suggest that BMI can be used as an index of muscle percentages as well as %Fat. As a final result, the distribution composition map of fat and muscle percentages for BMI does not show changes with age from infancy in preschool boys as a whole, but it does show such changes in girls. It is inferred that preschool girls show, due to early maturity, earlier changes (fat decrease) toward an integrated child's body than do boys.

Extent and distribution of white matter hyperintensities in normal aging, MCI, and AD

To analyze the extent and spatial distribution of white matter hyperintensities (WMH) in brain regions from cognitively normal older individuals (CN) and patients with mild cognitive impairment (MCI) and Alzheimer disease (AD). We studied 26 mild AD, 28 MCI, and 33 CN. MRI analysis included quantification of WMH volume, nonlinear mapping onto a common anatomic image, and spatial localization of each WMH voxel to create an anatomically precise frequency distribution map. Areas of greatest frequency of WMH from the WMH composite map were used to identify 10 anatomic regions involving periventricular areas and the corpus callosum (CC) for group comparisons. Total WMH volumes were associated with age, extent of concurrent vascular risk factors, and diagnosis. After correcting for age, total WMH volumes remained significantly associated with diagnosis and extent of vascular risk. Regional WMH analyses revealed significant differences in WMH across regions that also differed significantly according to diagnosis. In post-hoc analyses, significant differences were seen between CN and AD in posterior periventricular regions and the splenium of the CC. MCI subjects had intermediate values at all regions. Repeated measures analysis including vascular risk factors in the model found a significant relationship between periventricular WMH and vascular risk that differed by region, but regional differences according to diagnosis remained significant and there was no interaction between diagnosis and vascular risk. Differences in white matter hyperintensities (WMH) associated with increasing cognitive impairment appear related to both extent and spatial location. Multiple regression analysis of regional WMH, vascular risk factors, and diagnosis suggest that these spatial differences may result from the additive effects of vascular and degenerative injury. Posterior periventricular and corpus callosum extension of WMH associated with mild cognitive impairment and Alzheimer disease indicate involvement of strategic white matter bundles that may contribute to the cognitive deficits seen with these syndromes.

「似合う」評価における判定者の評価構造

The purpose of this study is to examine what characterizes certain evaluations from observers who estimate“clothes becoming to each wearer”that depend on the shape of the graph of frequency distribution of the evaluated values.The characteristic means the ability that the difference among clothes becoming to each wearer about their evaluations is able to detect in.36 models were worn in 20 sets of clothes, and the evaluation samples were made from each combimnation.56 observers estimated“clothes becoming to the wearer”in degrees of 1to 7 for every samples.The similar shapes of frequency distribution maps were integrated.They were classified in to four types;“bell”, “flat”, “M”and“No peak”.As for the power of detection, four decision standards were defined from tne structure of the difference in evaluation.And the test of the ratio was done in every decision standard.As a result, “No peak”type showed the highest detection power.The second was“flat”type.The third was“M”type.The fourth was“bell”type.This led to the next discovery.A difference in the distribution form shows a difference in structure of the“becoming”evaluation.The power of detection can be judged by the characteristics of the structure.About“becoming”, the mean of the observers isn't used, but it must think by four distribution types.

Abstract: Possible Geologic Influence on Salt Falls Associated with the Storage Caverns at Bryan Mound, Brazoria County, Texas

ABSTRACT A frequency distribution map of the number of salt falls associated with the various storage caverns at the Bryan Mound facility exhibits a pattern which suggests a geologic influence. To investigate this possibility, the upper 2500 feet of the undifferentiated Plio-Pleistocene strata which encloses the salt dome were studied for evidence of possible differential salt movement. Correlation of well logs in the area provided the basis for dividing the strata into seven mappable units. Each unit was isopached and in conjunction with a map of the salt stock evaluated for evidence of differential salt (spine) movement. The possible boundary zones between areas of differential movements were projected into the salt. In instances where similar trends were observed across the dome, a projection of the boundary zone was made through the salt stock. A composite of all the boundary zone projections was made and overlaid on the salt map. This map suggests that the salt stock is composed of two separate spine complexes separated by a complex boundary zone area. When this map is compared to the frequency distribution map, caverns with the large number of salt falls commonly are closely associated with the projected boundary zones particularly the zone separating the main spine complexes. Likewise those caverns which have experienced few or no salt falls tend to be located within the spine complexes. The isopachs of the two intervals which overlie the salt stock provide evidence for the more recent development of a younger spine.

Geographic and temporal variation in the incidence of melanism in peppered moth populations in America and Britain

Industrial melanism in the peppered moth (Biston betularia is the classic example of observable evolution by natural selection. The phenomenon has been most thoroughly documented in Britain, where once rare melanic phenotypes increased in frequency in concert with increased levels of atmospheric pollution generated by industrial development. Populations of the American subspecies of the peppered moth (B. betularia cognataria) also experienced increases in melanisms, which are especially well documented in southern Michigan. Following a succession of governmental regulations designed to improve air quality, melanic phenotypes have been on the decline in moth populations in the United Kingdom and the United States. In both countries, the declines in melanism appear to be correlated primarily with reductions in atmospheric sulfur dioxide. Detailed studies of the evolutionary parallels have focused mainly on two locations: Caldy Common (near Liverpool) in England, and the George Reserve (near Detroit) in the United States. We have expanded the geographic range of American samples to include northeastern Pennsylvania and southwestern Virginia, and we have conducted a national survey in Britain to produce a current melanic frequency distribution map. The results clearly show that the decline in melanism is widespread in both countries, and the changes are generally consistent with decreases in levels of atmospheric SO2.