Showing papers by "Tulane University published in 1986"
TL;DR: Numerical results for atoms, positive ions, and surfaces are close to the exact correlation energies, with major improvements over the original LM approximation for the ions and surfaces.
Abstract: Langreth and Mehl (LM) and co-workers have developed a useful spin-density functional for the correlation energy of an electronic system. Here the LM functional is improved in two ways: (1) The natural separation between exchange and correlation is made, so that the density-gradient expansion of each is recovered in the slowly varying limit. (2) Uniform-gas and inhomogeneity effects beyond the randomphase approximation are built in. Numerical results for atoms, positive ions, and surfaces are close to the exact correlation energies, with major improvements over the original LM approximation for the ions and surfaces.
16,378 citations
TL;DR: Improvements over other simple functionals are also found in the exchange contributions to the valence-shell removal energy of an atom and to the surface energy of jellium within the infinite barrier model.
Abstract: The electronic exchange energy as a functional of the density may be approximated as ${E}_{x}[n]={A}_{x}\ensuremath{\int}{d}^{3}r{n}^{\frac{4}{3}}F(s)$, where $s=\frac{|\ensuremath{
abla}n|}{2{k}_{F}n}$, ${k}_{F}={(3{\ensuremath{\pi}}^{2}n)}^{\frac{1}{3}}$, and $F(s)={(1+1.296{s}^{2}+14{s}^{4}+0.2{s}^{6})}^{\frac{1}{15}}$. The basis for this approximation is the gradient expansion of the exchange hole, with real-space cutoffs chosen to guarantee that the hole is negative everywhere and represents a deficit of one electron. Unlike the previously publsihed version of it, this functional is simple enough to be applied routinely in self-consistent calculations for atoms, molecules, and solids. Calculated exchange energies for atoms fall within 1% of Hartree-Fock values. Significant improvements over other simple functionals are also found in the exchange contributions to the valence-shell removal energy of an atom and to the surface energy of jellium within the infinite barrier model.
3,500 citations
TL;DR: In this article, it is argued that even the exact Kohn-Sham potential veff(r), which generates the exact density in a self-consistent field calculation, generates a band structure which underestimates the gap.
Abstract: How can the fundamental band gap of an insulator be predicted? As a difference of ground-state energies, the fundamental gap seems to fall within the reach of density functional theory, yet the predicted gaps from band structure calculations within the local density approximation (LDA) are about 40% too small. It is argued here that even the exact Kohn-Sham potential veff(r), which generates the exact density in a self-consistent-field calculation, generates a band structure which underestimates the gap. Within the context of the band gap problem, several recent developments in the density-functional theory of many-electron systems are reviewed: (1) The Langreth-Mehl approximation to the Kohn-Sham exchange-correlation energy and potential, based upon the Langreth-Perdew wavevector analysis of the density gradient expansion. This functional leads to more accurate ground-state energies and densities than those of the LDA with little change in the calculated band structures of solids. (2) The derivative discontinuity of the exchange-correlation energy, which is responsible for substantial underestimation of the fundamental gap by even the exact Kohn-Sham potential. (3) The self-interaction correction, which yields accurate gaps in insulators only by virtue of its orbital-dependent potential. (4) The density response function of the uniform electron gas, which suggests that the LDA gives a good estimate of the exact Kohn-Sham potential for a semiconductor with a weak periodic potential. In short, several very different (but admittedly approximate) numerical calculations suggest that most of the error in the LDA fundamental gap would persist in the gap of the exact Kohn-Sham band structure. This error would persist in any attempt to calculate the gap from LDA total energy differences for clusters of increasing size.
708 citations
TL;DR: The isolation of an HTLV- III-related retrovirus, STLV-III/Delta, from rhesus macaques with transmissible simian AIDS and from asymptomatic sooty mangabeys is reported.
Abstract: Acquired immune deficiency syndrome (AIDS) has become a worldwide epidemic1–6, so the development of vaccines and antiviral agents effective against the causative agent, human T-lymphotropic virus type III (HTLV-III), is vital. This work would be greatly simplified if a suitable animal model could be developed. Here we report the isolation of an HTLV-III-related retrovirus, STLV-III/Delta, from rhesus macaques (Macaca mulatta) with transmissible simian AIDS (SAIDS) and from asymptomatic sooty mangabeys (Cercocebus atys). SAIDS was initially diagnosed in several macaques previously inoculated with tissue homogenates of mangabey origin. Western blot analysis of both the mangabey and macaque sera demonstrated the presence of antibody cross-reactive primarily with the HTLV-III proteins p24 and p61. In a related experiment, analysis of these same sera revealed simian antibody to STLV-III/Delta proteins similar, but not identical, to those of HTLV-III with estimated relative molecular masses (Mrs) of 16,000 (16K), 26K, 35K, 45K, 60K and 110K. Infection of the mangabey, an African primate, with an HTLV-III-related virus may provide a clue to the origin of HTLV-III in humans. The apparent difference in susceptibility to SAIDS-like disease between infected macaques and mangabeys suggests that these species may respond differently to STLV-III infection.
418 citations
TL;DR: The somatotopic organization of M‐I was neither a single topographic representation, nor two serial or mirror symmetric representations, nor a “nesting about joints” representation, and is more adequately described as a mosaic of regions, each representing movements of a restricted part of the body, with multiple representations of movements that tend to be somatOTopically related.
Abstract: Microstimulation and anatomical techniques were combined to reveal the organization and interhemispheric connections of motor cortex in owl monkeys. Movements of body parts were elicited with low levels of electrical stimulation delivered with microelectrodes over a large region of precentral cortex. Movements were produced from three physiologically defined cortical regions. The largest region, the primary motor field, M-I, occupied a 4-6mm strip of cortex immediately rostral to area 3a. M-I represented body movements from tail to mouth in a grossly somatotopic mediolateral cortical sequence. Specific movements were usually represented at more than one location, and often at as many as six or seven separate locations within M-I. Although movements related to adjoining joints typically were elicited from adjacent cortical sites, movements of nonadjacent joints also were produced by stimulation of adjacent sites. Thus, both sites producing wrist movements and sites producing shoulder movements were found next to sites producing digit movements. Movements of digits of the forepaw were evoked at several locations including a location rostral to or within cortex representing the face. Overall, the somatotopic organization did not completely correspond to previous concepts of M-I in that it was neither a single topographic representation, nor two serial or mirror symmetric representations, nor a “nesting about joints” representation. Instead, M-I is more adequately described as a mosaic of regions, each representing movements of a restricted part of the body, with multiple representations of movements that tend to be somatotopically related. A second pattern of representation of body movements, the supplementary motor area (SMA), adjoined the rostromedial border of M-I. SMA represented the body from tail to face in a caudorostral cortical sequence, with the most rostral portion related to eye movements. Movements elicited by near-threshold levels of current were often restricted to a single muscle or joint, as in M-I, and the same movement was sometimes multiply represented. Typically, more intense stimulating currents were required for evoking movements in SMA than in M-I. A third motor region, the frontal eye field (FEF), bordered the representation of eyelids and face in M-I. Eye movements elicited from this cortex consisted of rapid horizontal and downward deviation of gaze into the contralateral visual hemifield.
409 citations
TL;DR: An elastic constitutive relation for cancellous bone tissue is developed and it is shown that the principal axes of the stress, strain and fabric tensors all coincide at remodeling equilibrium.
Abstract: An elastic constitutive relation for cancellous bone tissue is developed. This relationship involves the stress tensor T, the strain tensor E and the fabric tensor H for cancellous bone. The fabric tensor is a symmetric second rank tensor that is a quantitative stereological measure of the microstructural arrangement of trabeculae and pores in the cancellous bone tissue. The constitutive relation obtained is part of an algebraic formulation of Wolff's law of trabecular architecture in remodeling equilibrium. In particular, with the general constitutive relationship between T, H and E, the statement of Wolff's law at remodeling equilibrium is simply the requirement of the commutativity of the matrix multiplication of the stress tensor and the fabric tensor at remodeling equilibrium, T*H* = H*T*. The asterisk on the stress and fabric tensor indicates their values in remodeling equilibrium. It is shown that the constitutive relation also requires that E*H* = H*E*. Thus, the principal axes of the stress, strain and fabric tensors all coincide at remodeling equilibrium.
399 citations
TL;DR: It is concluded that muscle receptors are a prominent, if not primary, determinant of joint position sense, and capsular receptors may have a secondary role.
309 citations
TL;DR: The main technical tools are Connes' spatial theory and Haagerup's theory on operator-valued weights as discussed by the authors, and Jones' theory on index of (II 1−) subfactors is generalized to arbitrary factors.
262 citations
TL;DR: In this paper, the appropriateness of procedures is discussed in terms of reasons why the appropriate procedure sometimes becomes a predominant concern, and it is shown that under endorsement-context conditions in which subjects thought their responses were used to determine whether their experimenter would be hired as someone placed in charge of conducting research subjects expressed uniformly greater resentment in the low-justification conditions than in the high justification conditions.
235 citations
TL;DR: In this article, the determinants of perceived ease of movement within an organization among two groups of clerical employees were investigated, and the relationship between perceived ease-of-movement and job satisfaction was investigated.
Abstract: This study investigated the determinants of perceived ease of movement within an organization among two groups of clerical employees. It also investigated the relationship between perceived ease of...
216 citations
01 Jan 1986
TL;DR: The authors argues that there is a basis for rethinking equity theory and that such an enterprise is a worthwhile precursor to further research on the psychology of injustice, and argues that equity theory seems to have outlived its usefulness.
Abstract: Equity theory (Adams, 1965; Walster, Berscheid, & Walster, 1973) seems to have outlived its usefulness. Can it—should it—be revised or recon-ceptualized? This chapter argues that there is a basis for rethinking equity theory and that such an enterprise is a worthwhile precursor to further research on the psychology of injustice.
TL;DR: The authors pense generalement que tous les univers fermes S 3 en expansion, qui verifient les conditions d'energie standard, s'effondrent a nouveau vers une seconde singularite.
Abstract: On pense generalement que tous les univers fermes S 3 en expansion, qui verifient les conditions d'energie standard, s'effondrent a nouveau vers une seconde singularite. On montre que c'est faux, meme pour des univers de Friedmann
TL;DR: In this paper, an empirical investigation focused on person-window transactions in the physical medicine and rehabilitation environment was conducted in six hospitals, focusing on attributes of windows, view, daylight, and spaces perceived as insufficient in these respects.
Abstract: An empirical investigation focused on person-window transactions in the physical medicine and rehabilitation environment. Attributes of windows, view, daylight, and spaces perceived as insufficient in these respects were studied in six hospitals. Preference, environmental documentation, and behaviorsassociated with windows and windowless rooms were the subject of a two-part interview and questionnaire. The respondent group numbered 250 persons. Nonmetric multidimensional scaling (MDS) was utilized, yielding an array of 21 cognitive dimensions. From evaluations of 56 photographs that sampled a broad spectrum of spaces ranging from highly windowed to windowless, 8 visual dimensions were identified; and 13 nonvisual dimensions distilled from 89 written response items were identified that addressed degree of satisfaction and associated behaviors. Among the findings, ideal window and view conditions frequently contrasted the actual conditions in one's hospital setting; informative views of urban life and natur...
TL;DR: Two octapeptides containing tyrosine and valine in positions 3 and 6 were more active and more selective than their Phe-3 and Thr-6 counterparts, and showed a prolonged duration of action and were able to inhibit growth hormone release for at least 3 hr.
Abstract: In the search for selective and long-acting analogs of somatostatin, nearly 200 compounds were synthesized by solid-phase methods, purified, and tested biologically. Among these octapeptides, some contained N-terminal (Formula: see text) were 177 times and 113 times more potent, respectively, than somatostatin in tests for inhibition of growth hormone release. These two octapeptides containing tyrosine and valine in positions 3 and 6, respectively, were more active and more selective than their Phe-3 and Thr-6 counterparts, D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr-NH2 and D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Trp-NH2. D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Thr-NH2 was also about 6 times more potent than its L-Trp-4 diastereoisomer. The analogs D-Phe-Cys-Tyr-Lys-Val-Cys-Thr-NH2 and D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH2 showed a prolonged duration of action and were able to inhibit growth hormone release for at least 3 hr. Analogs of both Phe-3/Thr-6 and Tyr-3/Val-6 classes also suppressed the release of insulin and glucagon in rats and pentagastrin-induced secretion of gastric acid in dogs, but their potencies in these tests were much smaller than the growth-hormone-release inhibitory activity. Some of these analogs possessed antitumor activities as shown by the inhibition of growth of animal models of prostate, mammary, and ductal pancreatic tumors.
TL;DR: Intralesional alpha-2 IFN is of benefit in the treatment of a single condyloma; its role in the Treatment of multiple lesions remains to be clarified.
Abstract: We conducted a multicenter double-blind study comparing human recombinant intralesional alpha-2 interferon (IFN) and placebo in 237 patients with the clinical diagnosis of condyloma acuminatum or verruca plantaris. A single wart on each patient was injected with 0.1 mL containing 10(6) IU of IFN, 10(5) IU of IFN, or placebo three times weekly for three weeks, and the response to treatment was followed up for 12 weeks. Among 91 of the 114 patients with condyloma acuminatum who completed the study, complete clearing of the treated wart occurred in 16 (53%) of 30 patients receiving 10(6) IU of IFN compared with six (19%) of 32 receiving 10(5) IU of IFN and four (14%) of 29 receiving placebo. In the group of 100 patients with plantar warts, there was no apparent benefit associated with interferon administration. Seven patients (3%) had treatment discontinued due to adverse reactions. Intralesional alpha-2 IFN is of benefit in the treatment of a single condyloma; its role in the treatment of multiple lesions remains to be clarified. Its role in the treatment of verruca plantaris, where no response was seen, also remains to be clarified.
TL;DR: Thermophilic bacteria which contain N4-methylcytosine rather than m5C in their genomes may thereby largely avoid heat-induced mutation due to deamination, which is incurred by the many organisms that contain m5 C in their DNA.
Abstract: The heat-induced conversion of 5-methylcytosine (m5C) residues to thymine residues and of cytosine to uracil residues in single-stranded DNA was studied. The calculated rates for deamination at 37°C and pH 7.4 were ∼9.5×10−10 and 2.1×10−10 sec−1, respectively. N4-Methyldeoxycytidine, which is in the DNA of certain thermophilic bacteria, was more heat-resistant than was deoxycytidine and much more than was 5-methyldeoxycytidine. Thermophilic bacteria which contain N4-methylcytosine rather than m5C in their genomes may thereby largely avoid heat-induced mutation due to deamination, which is incurred by the many organisms that contain m5C in their DNA.
TL;DR: The morphology of local circuit neurons develops during the period after they migrate into cortex, as each neuron sprouts dendrites which extend, branch and produce spines, and ends by day 21.
TL;DR: A magnetic levitation control system is built as a classroom demonstration device for systems and control courses as mentioned in this paper, where linearization and phase-lead compensation techniques are used to control the unstable nonlinear system.
Abstract: A magnetic levitation control system is built as a classroom demonstration device for systems and control courses. System linearization and phase-lead compensation techniques are used to control the unstable nonlinear system.
TL;DR: Ten ankles in nine patients with eight posteromedial lesions, six Stage 3 and two Stage 4, and two anterolateral lesions, both Stage 4 were treated arthroscopically for removal of the loose fragment and curettage of the osteochondral bed.
Abstract: Flake fractures of the talar dome involving the cartilaginous surface and subchondral bone have been called transchondral talar dome fractures, a term specific for both anatomical and traumatic etiology of this lesion, and more descriptive than the previously used "osteochondritis dissecans" of the talus. The diagnosis is made by standard ankle radiographs and the lesion should be suspected in all "sprained ankles" that have continued disability following standard treatment. Surgical treatment has been recommended for Stage 3 and Stage 4 (detached/displaced fragments). Surgical treatment for removal of symptomatic lesions has, in the past, involved an arthrotomy for exposure with removal of the fracture fragment and curetting and drilling of the donor bed. Posteromedial fractures are often hard to reach through a standard approach and exposure may require an osteotomy of the medial malleolus. The use of the arthroscope in both confirmation of diagnosis and surgical treatment has proved to be beneficial in the treatment of these symptomatic fractures. The technique allows direct visualization of the pathology with adequate debridement with minimal iatrogenic trauma and early mobilization and return to preinjury status. The series includes 10 ankles in nine patients with eight posteromedial lesions, six Stage 3 and two Stage 4, and two anterolateral lesions, both Stage 4. All patients were treated arthroscopically for removal of the loose fragment and curettage of the osteochondral bed. Subjective and objective follow-up at a minimum of 6 months revealed good results in nine of the ten patients.
TL;DR: It is suggested, based on antinociceptive mechanisms, that the individual components of the antiopiate system might function differently from naloxone, and the biological activity, behavioral activity, and functional effects of this proposed opiate antagonist system are reviewed.
TL;DR: At 10 years, the cumulative overall survival for Stage I melanoma of the limbs, combining regional perfusion and conservative excisional surgery, was 77%, and the overall 10‐year survival for regional melanoma was 41%, ranging from 23% for intransit metastases to 51% for patients with positive regional nodes treated by perfusion
Abstract: A review of the development of regional chemotherapy by perfusion is presented. Techniques have been developed for most regions of the body. Early response rates ranged from 48% for glioblastoma and 55% with carcinoma to 67% with soft tissue sarcoma and 84% with melanoma. By 1984, 1325 patients had been perfused 1509 times. The best responses have occurred with melanoma and soft tissue sarcoma of the limbs. Thus, at 10 years, the cumulative overall survival for Stage I melanoma of the limbs, combining regional perfusion and conservative excisional surgery, was 77%. The best results occurred in female patients with upper-limb disease (83%), and the poorest results were in male patients with lower-limb disease (53%). The overall 10-year survival for regional melanoma was 41%, ranging from 23% for in-transit metastases to 51% for patients with positive regional nodes treated by perfusion and regional lymph node dissection. The 10-year survival for perfusion and limb-sparing excision for soft tissue sarcoma was 65%. Advantages and complications are presented and discussed. Questions and plans for the future are reviewed.
TL;DR: Data suggest that the cell volume response of astrocytes in hypoosmotic medium involves the net movement of osmoles by a mechanism dependent on cellular energy and tightly coupled to the (Na, K)‐ATPase ion pump.
Abstract: Cell volume regulation and energy metabolism were studied in primary cultured cerebral astrocytes during exposure to media of altered osmolarity. Cells suspended in medium containing 1/2 the normal concentration of NaCl (hypoosmotic) swell immediately to a volume 40–50% larger than cells suspended in isoosmotic medium. The cell volume in hypoosmotic medium then decreases over 30 min to a volume approximately 25% larger than cells in isoosmotic medium. In hyperosmotic medium (containing twice the normal concentration of NaCl), astrocytes shrink by 29%. Little volume change occurs following this initial shrinkage. Cells resuspended in isoosmotic medium after a 30 min incubation in hypoosmotic medium shrink immediately to a volume 10% less than the volume of cells incubated continuously in isoosmotic medium. Thus, the regulatory volume decrease (RVD) in hypoosmotic medium involves a net reduction of intracellular osmoles. The RVD is partially blocked by inhibitors of mitochondrial electron transport but is unaffected by an inhibitor of glycolysis or by an uncoupler of oxidative phosphorylation. Inhibition of RVD by these metabolic agents is correlated with decreased cellular ATP levels. Ouabain, added immediately after hypoosmotic induced swelling, completely inhibits RVD, but does not alter cell volume if added after RVD has taken place. Ouabain also inhibits cell respiration 27% more in hypoosmotic medium than in isoosmotic medium indicating that the (Na, K)-ATPase-coupled ion pump is more active in the hypoosmotic medium. These data suggest that the cell volume response of astrocytes in hypoosmotic medium involves the net movement of osmoles by a mechanism dependent on cellular energy and tightly coupled to the (Na, K)-ATPase ion pump. This process may be important in the energy-dependent osmoregulation in the brain, a critical role attributed to the astrocyte in vivo.
TL;DR: In this article, the first principal component introduces a negative bias into the resulting correlations that seriously compromises subsequent analysis, and the extent of bias is not reduced by increasing sample size; however, it is inversely proportional to the number of variables.
TL;DR: Observations suggest functional roles for 1,25-dihydroxyvitamin D3 and its receptors in cardiac muscle, possibly in regulating intracellular effects of calcium.
TL;DR: It is demonstrated that stress has a rapid and dramatic effect on testicular steroid secretion in both farm-reared and wild alligator populations, with significant differences in mean testosterone and corticosterone levels.
Abstract: In order to test the effect of acute stress on gonadal hormone secretion in reptiles, six mature male alligators were captured, and a blood sample was taken within 5 min of capture. Additional blood samples were taken at timed intervals for up to 41 hr, and plasma testosterone and corticosterone were measured by radioimmunoassay. Plasma testosterone declined to 50% of the initial value by 4 hr and dropped to less than 10% of initial by 24 hr. Plasma corticosterone increased during the first 12 hr, declined at 24 hr, and rose again at 40 hr. Blood samples from male alligators collected in North and South Carolina, south Florida, and in south Louisiana in two consecutive breeding seasons were also assayed for testosterone and corticosterone. In these populations there were significant differences in mean plasma testosterone and corticosterone levels. Elevated corticosterone levels were consistently seen in alligators caught in traps and from which a blood sample was taken several hours later. Plasma testosterone, although consistently lower in trapped alligators, did not show a negative correlation with plasma corticosterone. Farm-reared alligators bled once, released, and bled again at 24 hr also showed a highly significant suppression of testosterone secretion. These results demonstrate that stress has a rapid and dramatic effect on testicular steroid secretion in both farm-reared and wild alligators.
TL;DR: The results indicated a significant lengthening in knee joint laxity between preexercise and postexercise in the left knee as measured at 15 and 20 pounds of passive displacement force, which document an in vivo increase in the anterior laxity of the knee joint due to exercise.
Abstract: Knee injuries are the topic of increasingly sophisticated research because of the importance in professional athletics as well as increasing participation in recreational sports. The role of conditioning and fatigue in these injuries remains controversial. Ligaments have high collagen content, and a viscoelastic response to stress would be expected. Because of the postulated relationship between laxity and knee ligament injuries, an experiment was designed using highly motivated athletes to test the hypothesis that exercise to the point of muscular fatigue may cause laxity of the knee and thereby place athletes at risk for ligamentous injury to the knee when fatigued. An exercise protocol was designed to produce muscle fatigue in the hamstring and quadriceps muscle groups. Knee ligament laxity was tested prior to and subsequent to the exercise protocol. To document muscle fatigue, isokinetic testing of right knee flexion and extension power was used several times during the exercise protocol. A knee arthrometer (KT-1000) was used to quantitatively document ligamentous laxity before and after exercise. The results indicated a significant lengthening in knee joint laxity between preexercise and postexercise in the left knee as measured at 15 and 20 pounds of passive displacement force (P less than 0.05). Maximum manual displacement also demonstrated a significant increase in joint laxity (P = 0.02). The right knee, which had undergone isokinetic testing, demonstrated a similar tendency but without a statistically significant difference before and after exercise. There was no significant preexercise side to side difference, but postexercise measurements demonstrated a left-right difference at 15 pounds, 20 pounds, and maximum manual displacement of statistical significance (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
TL;DR: Immunohistochemical as well as radioimmunochemical studies provided further insights into the natural occurrence of the nonpeptide and the distribution of DSIP-like material in the body, suggesting possible relations of the peptide to certain diseases.
TL;DR: Because the pattern of ovum development in wild-caught females was the same as that observed in laboratory females, it is believed that the laboratory observations demonstrate processes which occur in the natural environment.
Abstract: Pairs of laboratory–reared F1, and F2 males and females of Notropis leedsi were observed in aquaria. Analyses of spawning histories and ovum diameter histograms showing the pattern of ovum development demonstrated that females produced multiple clutches of eggs. Each clutch is comprised of oocytes which undergo synchronous development and are oviposited within a relatively short period of time. Examinations of collections from streams in Florida and Georgia showed that N. leedsi has a spawning season which lasts at least from May to September. Because the pattern of ovum development in wild-caught females was the same as that observed in laboratory females, we believe that our laboratory observations demonstrate processes which occur in the natural environment. A total of 193 spawning intervals was observed in 34 pairs kept at 22–26°C in the laboratory. The interspawning intervals ranged from 3 to 10 days, with a mean of 4.6 days and a mode of 4 days. The clutches ranged in size from 26 to 28 ova for females of 36.7–52.5 mm standard length.
TL;DR: In this article, a technique of diagnostic and operative arthroscopy of the elbow and its indications are presented, and the intra-articular anatomy is described, where the close proximity of vital neurovascular structures and the size constraints of the joint itself make a thorough knowledge of the anatomy and close attention to detail crucial to this procedure.
TL;DR: In this paper, the Friedmann universe is quantized in conformal time, and it is shown that any universal wave function which does not violate a Quantum Copernican Cosmological Principle can automatically solve the Flatness Problem without having to invoke inflation.