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The Western Syncline hosts reduced-facies, or Kupferschiefer-type, sedimentary rock-hosted stratiform Cu deposits (SSC) in the lowermost meters of the Nonesuch Formation, which is part of a thick section of clastic sedimentary rocks that comprise the upper fill of the Mesoproterozoic Midcontinent Rift of North America. Located in the Porcupine Mountains Cu district in Upper Peninsula, Michigan, these blind deposits were discovered in 1956, but are not yet developed, although recent renewed interest may result in near-term production. The deposits are distinguished by their relatively undeformed nature and lack of superposed hydrothermal events. Prior to lithification, chalcocite mineralization replaced diagenetic pyrite within two discrete tabular, albeit discontinuous, potential orebodies referred to as the lower Cu-bearing sequence (LCBS) and the upper Cu-bearing sequence (UCBS). The Top Cu Zone transgresses lithologic boundaries, suggesting that a limited volume of Cu-bearing fluids moved vertically upwards through the unlithified stratigraphy, since reductant pyritic rocks above this zone are essentially barren of Cu. The total Cu inventory that has a reasonable expectation of economic extraction is 3678 M lbs. of Cu with 15.3 M oz. of byproduct Ag. When a cutoff grade of 0.9% Cu over a minimum thickness of 2 m is applied to justify an underground room-and-pillar mine, the LCBS and UCBS are not continuous over the Western Syncline. Sedimentology is the first-order control of potential ore and its continuity; dark-gray shales and siltstones deposited under low-energy, anoxic conditions are preferred host rocks, whose thickness must be >2 m to be potential ore since host-rock thickness determines economic viability of extraction. Furthermore, stratigraphy influences the time constraints on mineralization as the lithification process impedes vertical permeability and thus the flow of Cu-bearing fluids upward through the unlithified section. Syn-sedimentary tectonic movements, likely along pre-existing buried faults, are a third-order control as the thickness of host rocks is enhanced under such conditions. Therefore, an understanding of the depositional and tectonic history throughout the Western Syncline is fundamental to understanding the limits of possible economic exploitation and to optimizing ore extraction.

Copperwood is located in Gogebic County, Upper Peninsula, Michigan, within the Porcupine Mountains copper district. It was discovered in 1956 and, in 2008, Orvana Minerals Corp began exploration and development work with production projected in the near future. Stratiform copper mineralization is hosted by gray to black shales and siltstones of the basal Nonesuch Formation. Copper mineralization is overlain by laminated gray siltstones of the Nonesuch Formation and is underlain by red-bed sandstones, conglomerates, and minor siltstones of the Copper Harbor Formation; these rocks are part of a thick section of clastic sedimentary rocks that comprise the upper fill of the Mesoproterozoic (1.1–1.0 Ga) Midcontinent rift. The copper deposit is a tabular body that averages 2.5 m thick, lacks significant basal undulations, and dips 8° to 12° northward on the southwest limb of the Western syncline, an open fold with a shallow plunge to the northwest. Chalcocite is the only Cu-bearing mineral in the orebody and occurs as concentrations along stratigraphic laminations and as disseminated grains. Within the orebody, there is no mineral or metal zoning; Cu, Ag, and S are strongly enriched, Zn is very slightly enriched and Pb and Co lack enrichment. Gangue minerals in the orebody are quartz, clinochore, muscovite/illite, plagioclase, K-feldspar, calcite, and hematite, which are consistent with temperatures of less than 130°C. Only one significant fault, a shallow NW-dipping reverse fault with displacement of up to 7 m, has disturbed the section. The mineralized zone at Copperwood is stratigraphically equivalent to that at the White Pine mine, but Copperwood lacks the structural complexity and the hydrothermal overprint manifested by the native Cu mineralization at White Pine. Reported Canadian National Instrument 43-101-compliant measured, indicated, and inferred resources are 33 million metric tonnes (Mt) of 1.60% Cu and 4.1 ppm Ag for total contained Cu of about 1.165 billion lb and 4.32 Moz of Ag. The characteristics of Copperwood are consistent with those of reduced-facies, or Kupferschiefer-type, sedimentary rock-hosted stratiform copper deposits. The proposed genetic model is chalcocite replacement of pyrite in unlithified sediments during diagenesis as a result of emanating upward-focused, compaction-driven, Cu-bearing saline basinal waters with Cu leached from the underlying red-bed paleoquifer. The simplicity of the mineralizing event and the undeformed nature of the deposit distinguish Copperwood from most other examples of reduced-facies, or Kupferschiefer-type, sedimentary rock-hosted stratiform copper deposits throughout the world.

Background Excessive emotional responding is considered to be a hallmark of borderline personality disorder (BPD). The affect-modulated startle response is a reliable indicator of emotional processing of stimuli. The aim of this study was to examine emotional processing in BPD patients (n = 27) and healthy control subjects (n = 21). Methods Participants viewed an intermixed series of unpleasant, borderline-salient (e.g., “hate”), and neutral (e.g., “view”) words and were instructed to think about the meaning of the word for them personally while eyeblink responses were assessed. Results The BPD patients exhibited larger startle eyeblink during unpleasant but not neutral words, indicating exaggerated physiological affect. This finding remained significant when we controlled for comorbid diagnoses, including generalized anxiety disorder and post-traumatic stress disorder. Greater symptom severity was associated with greater affective-startle difference scores (unpleasant-neutral). Conclusions Consistent with the symptom of affective dysregulation, these results suggest an abnormality in the processing of unpleasant emotional stimuli by BPD patients.

The opponent process theory of emotion [Solomon, R.L., and Corbit, J.D. (1974). An opponent-process theory of motivation: I. Temporal dynamics of affect. Psychological Review, 81, 119-143.] predicts a temporary reversal of emotional valence during the recovery from emotional stimulation. We hypothesized that this affective contrast would be apparent in asymmetrical activity patterns in the frontal lobes, and would be more apparent for left frontally active individuals. The present study tested this prediction by examining EEG asymmetries during and after blocked presentations of aversive pictures selected from the International Affective Picture System (IAPS). 12 neutral images, 12 aversive images, and 24 neutral images were presented in blocks. Participants who were right frontally active at baseline did not show changes in EEG asymmetry while viewing aversive slides or after cessation. Participants left frontally active at baseline, however, exhibited greater relative left frontal activity after aversive stimulation than before stimulation. Asymmetrical activity patterns in the frontal lobes may relate to affect regulatory processes, including contrasting opponent after-reactions to aversive stimuli.

Recent findings have revealed very slow (

Based on the Inventory of Interpersonal Problems (IIP), the IIP-PD and the IIP-C screening scales were developed to distinguish personality disorder (PD) from non-PD and Cluster C from other PD, respectively, in a clinic population. Two studies were conducted to determine (a) validity and reliability of these IIP scales for PD screening in a nonclinical population, (b) specificity of IIP-C for identifying Cluster C, and (c) usefulness of the IIP scales for screening Cluster A. College students were screened using the IIP scales (Study 1, N = 454, Study 2, N = 87). High and low scorers completed PD-related questionnaires in Study 1 and a clinical interview for PD symptomatology in Study 2. Results indicated strong test-retest reliability, internal consistency, and factorial, convergent, and external validity. The scales tapped a common deficit in interpersonal relatedness, with some distinction between externalizing and internalizing dimensions, respectively, and both scales were positively and significantly associated with schizotypal traits. In conclusion, the IIP-PD and IIP-C are useful and valid screening instruments for identifying any versus no PD in nonclinical populations.

Objectives. Four patients with previous repair of tetralogy of Fallot and ventricular tachycardia underwent map-guided surgery to ablate the arrhythmias. Background. Although patients with repaired tetralogy of Fallot are at increased risk of sudden death due to ventricular tachycardia, little is known of the origin and mechanism of this arrhythmia. Methods. A customized right ventricular balloon with 112 electrodes was used to record endocardial activation and, where possible, simultaneous epicardial recordings were obtained with a sock electrode array. Three patients had an aneurysm of the right ventricular outflow tract and one had a septal aneurysm. All had moderate to severe pulmonary valve insufficiency. Preoperative electrophysiologic study demonstrated inducible rapid (cycle length 180 to 300 ms) hemodynamically unstable monoform ventricular tachycardias. Results. Intraoperatively, five different tachycardias (two in one patient) were induced and mapped. The sites of earliest activation were located in the subendocardium of the right ventricular outflow tract in all, but they varied widely among the septum, free wall and parietal band and could not be identified by visible scar. All were due to a macroreentrant circuit initiated by a critical delay in activation beyond a functional arc of block. Two patients treated by cryoablation while the heart was beating and perfused at normal temperature had inducible ventricular tachycardia postoperatively. In the two subsequent patients, the application of cryoablation under anoxic cardiac arrest resulted in noninducibility of arrhythmia. Conclusions. Ventricular tachycardia in tetralogy of Fallot in these four patients was caused by macroreentry in the right ventricular outflow tract. Surgical success depends on detailed mapping and cryoablation under anoxic cardiac arrest. In patients at risk of sudden death, map-directed surgery may offer distinct advantages over either implantable devices or drug therapy.

1. The presence of a natural anti-human hemolysin, only active against Group I and Group II cells, was demonstrated in over 50 guinea pigs, obtained from different sections of the surrounding country. It was shown that, in a majority of the sera tested, this hemolysin would be a contributing factor to an excess of amboceptor in the reaction, in the quantities of complement used in an antihuman complement fixation reaction. The hemolysin is specific, in as far as it can be absorbed with either Group I or Group Il cells, but cannot be absorbed with Group III or Group IV cells. 2. To determine the effect of the isohemolysins in human serum, twenty sera were tested against cell suspensions of the four human groups. Tests were also run with twenty-six human sera against all four group cell suspensions, with complement that had the natural anti-human hemolysin absorbed from it. In both experiments various degrees of hemolysis were obtained with all but two sera against cell suspensions from Groups I, II, and III, but no hemolysis was obtained with any serum against a Group IV cell suspension. 3. The importance of the human isohemolysins and the natural anti-human hemolysm in complement was demonstrated by performing complement fixation tests upon twenty-six human sera, cell suspensions of all four human groups for each serum tested being used. A marked variation in the reaction occurred with a large percentage of the sera tested. This variation in a single serum might be as great as a negative reading with Group I cells to a double plus reading with Group IV cells. 4. That the isohemolysins, alone, in human serum are of importance in the reaction was shown by running complement fixation tests upon seventeen human sera with the four group cell suspensions and complement from which the natural anti-human hemolysin had been absorbed. Results showed a much weaker reaction, in a large number of the sera, with Group I, Group II, and Group III cells than with Group IV cells. 5. Experiments to determine a relation between the human blood groups and natural anti-sheep hemolysin present in human serum gave negative results. It was shown, however, with twenty-six human sera tested against twenty-three different sheep cell suspensions that there is a wide variation in the activity of the natural anti-sheep amboceptor present in any human serum when it is tested against different sheep cell suspensions. A human serum capable of completely hemolyzing the cells of one sheep may fail to give any hemolysis whatever when tested against another sheep cell suspension. 6. Tests were made for natural anti-sheep hemolysin in guinea pig serum. The serum from sixteen different guinea pigs was tested against a total of twenty-one sheep cell suspensions. A natural anti-sheep hemolysin was present in all the guinea pigs tested against one of the sheep cell suspensions. The same guinea pigs tested against the other sheep cell suspensions failed to show any hemolysis.

To evaluate scar-type and matrix connective tissue and to assess their role in the diastolic dysfunction of hypertrophic cardiomyopathy, surgically resected subaortic myectomy specimens and several autopsy hearts from patients with hypertrophic cardiomyopathy were studied. Eighteen specimens were differentially stained by a newly developed method that precisely determines relative collagen content; these tissues were compared with postmortem hypertrophied and normal control subaortic specimens. Quantitation revealed a 72% higher level (36.5 vs. 22.1 micrograms collagen/mg protein) of stainable collagen in the hearts with hypertrophic cardiomyopathy than in hypertrophied control hearts. The endocardial plaque was quantitated morphometrically, and it constituted only 4.6 +/- 1.7% of the total increased collagen content in the cardiomyopathy specimens. For the matrix studies, the cardiomyopathy specimens were stained by a silver impregnation technique that identifies connective tissue elements not normally visible with routine histologic methods. There was a marked increase in content of all matrix components, both in areas of pathologic scarring and in "normal" zones. Whorls of matrix connective tissue were noted in regions of myocyte whorls, as well as independent of them. Thus, these studies revealed a striking increase of both scar-type and matrix connective tissue in hypertrophic cardiomyopathy. The extensive scarring and the pronounced interstitial and intercellular matrix connective tissue may contribute to the increased ventricular chamber stiffness and impaired relaxation in this disease.

Several available reports demonstrate the presence of infraslow activity (

Recent publications indicate the presence of infraslow activity (

Three levels (.5, 1.0, and 2.0 sec) of interstimulus interval (ISI) and presence vs absence of a masking task were manipulated in a human eyelid reflex conditioning situation. Through the use of a two-phase model of conditioning performance, it was concluded that (1) increasing the ISI and introducing a masking task increased the duration of Phase 1, (2) as ISI increased, the amount of conditioning decreased, (3) the trial-by-trial rate of change in response probability increased as a function of ISI, and (4) the masking task reduced operator limits. It was also noted that the typical ISI function is composed of rate effects at short ISis and conditioning limit effects at long ISIs and that the larger 0 at larger ISis does not follow from a model of the stimulus trace hypothesis.

Skin conductance responses were differentially conditioned using reinforcement schedules of 25%, 50%, 75%, and 100%, manipulated between subjects. Half of the subjects were informed about schedule contingencies, and half were uninformed. The interstimulus interval was 6 sec. Discrimination of first-interval responses (1.0-3.5 sec after conditioned stimulus [CS] onset) by informed subjects did not vary with the ratio variable, but that by uninformed subjects improved with increasing reinforcement ratio because of diminished response levels to the nonreinforced CS (CS-). Discrimination of second-interval responses (3.6-7.0 sec after CS onset) improved as a function of increasing reinforcement ratio because of elevated response levels to the reinforced CS (CS+), but the effect was not persistent across trials in informed subjects. Performance in the first and second intervals did not reflect sequential increments and decrements as a function of reinforced and nonreinforced trials. Third-interval responses (7.1-9.9 sec after CS on nonreinforced trials) were not affected by schedule manipulations, but unconditioned responses diminished with increasing reinforcement ratio. Information about schedule contingencies led to superior discrimination of first-, second-, and third-interval responses and to suppression of unconditioned responses.

Human conditioning performance decreases as a function of decreases in reinforcement ratio. It was shown that this effect is not exclusively a result of trial-by-trial increments and decrements associated with unconditioned stimulus presence vs. absence. Decreases in reinforcement ratio also increase the number of trials required before CRs emerge and decrease the limit of operators employed to describe performance once acquisition begins. The latter two effects were interpreted to mean, first, that more time is required by subjects to develop the associative network requisite to response acquisition and, second, that information about reinforcement schedules beyond trial-by-trial effects determines overall boundary conditions of performance. The results were discussed from an information processing perspective that differentiates between the acquisition of knowledge about the schedules and the trial-by-trial feed-back effects that shape performance.

A 52-year-old man with Ph1-positive chronic myelogenous leukemia (CML) developed a blastic transformation in which the predominant cell type micromegakaryocytes. He did not respond to treatment. A review of the 15 previously reported cases of patients with circulating megakaryocyte abnormalities in association with either CML or a Ph1 chromosome positive myeloproliferative disorder suggests a female predominance rather than the usual male predominance of CML. Survival of the six patients reported as megakaryoblastic transformation of CML as well as this patient was poor.

To assess some implications of incremental-decremental learning theories for classical conditioning, skin conductance response conditioning in humans was examined as a function of reinforcement schedule. First anticipatory responses (FARs: latency from 1.0 to 3.5 sec after signal onset) were not affected by reinforcement ratio, but, during the first half of training, the probability of second anticipatory responses (SARs: latency from 3.6 to 7.0 sec after signal onset) increased with increases in reinforcement ratio. FAR and SAR probabilities decreased across sequences of successively reinforced trials and increased across sequences of successively nonreinforced trials. These results are incompatible with the theoretical expectation that response likelihood should increase following reinforced trials and decrease following nonreinforced trials. Alternative accounts of the results are discussed.

With .2-sec bursts of white noise as both conditioned stimulus (CS) and unconditioned stimulus (UCS), conditioning of first-interval skin conductance responses was obtained when the intensity of the CS equaled and exceeded that of the UCS. There was no evidence that second-interval response conditioning occurred. Nonspecific response frequencies were also affected by the variations in stimulus intensity, this raising some question about typical controls employed in SCR conditioning. There was some evidence that second interval responses were suppressed by the intense CS values. It was concluded that the existence of simple conditioning with a CS/UCS intensity ratio equal to or greater than unity was contrary to the Pavlovian proposition that a CS must be biologically less salient than the UCS in order for conditioning to occur. It was noted, however, that the suppression of second-interval responses might indicate that anticipatory CRs which are not confounded with orienting reflexes are prevented from exhibiting a conditioning effect when a high CS/UCS intensity ratio is employed.

Thirty-six Ss, informed about the contingencies, were given differential SCR training with 3 different signals: CS+, CS−, and a signal which was random with respect to UCS occurrence. UCSs occurred randomly between trials and during random signal trials, were correlated with CS+ presence, and were absent during CS−. Employing nonspecific response frequency and amplitude, as well as responding during random signal trials, as baselines for comparison, evidence for both inhibitory and excitatory influences was obtained. The pattern of these influences was such as to question the proposition that a CS+ acquires general excitatory properties and a CS− acquires general inhibitory properties.

Human Ss were exposed to a discriminated punishment contingency with the aversive stimulus being an air puff to the cornea. In most Ss there was an increase in response probability (an eyelid reflex) across trials and an application of the two-phase model showed that the increases, though not great, were reliable. An analysis of the estimated parameter values showed that for only 5 of the 26 Ss did the pattern of parameter values conform to what would be expected on the basis of either two-factor or relative reinforcement theory. The results were, however, consistent with what might have been expected from giving Ss a low ratio intermittent reinforcement schedule in a more traditional classical conditioning arrangement.

An enormous literature has accumulated regarding the relative merits of the Sachs-Georgi and the Wassermann tests in the diagnosis of syphilis, a literature that is so filled with contradictions that an unprejudiced reader is utterly at a loss in evaluating the relative accuracy of the two tests. Some observers claim for the Sachs-Georgi reaction a greater specific value in the diagnosis of the disease than is possessed by the Wassermann reaction, while others conclude that the Sachs-Georgi test is less accurate or absolutely unreliable. In view of the discordant results recorded in the literature with the Sachs-Georgi test, we believed that it would be of some value to compare the results obtained with the two tests on routine specimens of blood sent to the laboratories of the Army Medical School for the Wassermann test. This work has covered a period of nearly one year and has been very carefully conducted