cssi/SciSciGPT-SciSciNet huggingface dataset:
Electrical properties of Cd, Zn and S ion-implanted layers in GaAs

Abstract The electrical properties of cadmium, zinc, and sulfur ion-implanted layers in gallium arsenide have been measured by the van der Pauw-Hall technique. Ion implantation was performed with the substrates held at room temperature. The dependence of sheet resistivity, surface carrier concentration, and mobility on ion dose and on post-implantation anneal temperature was determined. In the case of 60 keV Cd+ ions implanted into n-type substrates, a measurable p-type layer resulted when samples were annealed for 10 minutes at a temperature in the range 600—900°C. After annealing at 300—900°C for 10 minutes, 100 per cent electrical activity of the Cd ions resulted for ion doses ≤ 1014/cm2. The properties of p-type layers produced by implantation of 85 keV Zn+ ions were similar to those of the 60 keV cadmium-implanted layers, in that no measurable p-type behavior was observed in samples annealed below a relatively high temperature. However, in samples implanted with 20 keV Zn+ ions a p-type layer was obs...
Primary signet-ring cell carcinoma mimicking segmental Crohn's colitis

Primary signet-ring cell carcinoma of the colon is a rare entity with a dismal prognosis, mainly due to a delay in diagnosis. Here, we present a case of a 30-year-old Filipino woman who presented with symptoms mimicking inflammatory bowel disease. A barium enema and colonoscopy demonstrated a stricture in the rectosigmoid region. A biopsy revealed granulomatous changes indicative of inflammatory bowel disease. Despite initial improvement of her symptoms on total parenteral nutrition and steroids, the patient relapsed several weeks later with recurrent left lower quadrant pain. A subsequent biopsy revealed poorly differentiated signet-ring cell carcinoma of the colon. She was treated surgically with a left hemi-colectomy and primary repair. A high degree of suspicion is necessary to correctly diagnose these, often young, patients with primary signet-ring cell carcinoma early and have a positive impact on survival. The literature on primary signet-ring cell carcinoma is reviewed.
Effects of elevated carbon dioxide on gas exchange and photochemical and nonphotochemical quenching at low temperature in tobacco plants varying in Rubisco activity.

Elevated (700 μmol mol−1) and ambient (350 μmol mol−1) CO2 effects on total ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activity, photosynthesis (A), and photoinhibition during 6 d at low temperature were measured on wild type (WT), and rbcS antisense DNA mutants (T3) of tobacco (Nicotiana tabacum L.) with 60% of WT total Rubisco activity (Rodermel et al. (1988) Cell 55: 673–681). Prior to the low temperature treatment, A and quantum yield of PSII photochemistry in the light adapted state (φPSII) were significantly lower in T3 compared to WT at each CO2 level. At this time, total nonphotochemical quenching (NPQTotal) levels were near maximal (0.75–0.85) in T3 compared to WT (0.39–0.50). A was stimulated by 107% in T3 and 25% in WT at elevated compared to ambient CO2. Pre-treatment acclimation to elevated CO2 occurred in WT resulting in lower Rubisco activity per unit leaf area and reduced stimulation of A. At low temperature, A of WT was similar at elevated and ambient CO2 while stimulation of A by elevated CO2 in T3 was reduced. In addition, at low temperature we measured significantly lower photochemical quenching at elevated CO2 compared to ambient CO2 in both genotypes. NPQTotal was similar (0.80–0.85) among all treatments. However, a larger proportion of NPQTotal was composed of qI,d, the damage subcomponent of the more slowly relaxing NPQ component, qI, in both genotypes at elevated compared to ambient CO2. Greater qI,d, at elevated CO2 during and after the low temperature treatment was not related to pre-treatment differences in total Rubisco activity.
Serotonin and Its Role in Headache Pathogenesis and Treatment

Objective This review tries to consolidate the literature on changes in serotonin and the importance of these changes for understanding headache pathogenesis and determining treatment. A model is presented that integrates previous serotonin studies and offers an explanation for apparent contradictions in the literature. Data sources Fifty-four journal articles that described a relationship between serotonin and headache in animal and human models were identified through Medline search and bibliography and reviewed. Alterations in serotonin, headache, and clinical situations influencing headache activity were examined. Data synthesis Abnormalities in blood vessels have traditionally been implicated in the pathogenesis of migraine headaches, and excessive muscle contraction in tension-type headaches. Interestingly, both vascular and muscular changes occur in both migraine and tension-type headache. Recently, biochemical changes have been demonstrated in both types of headaches. These biochemical changes are postulated to precede and possibly cause the subsequent changes in blood vessels and muscle tone, known to occur in chronic headaches. Serotonin has been the most widely studied neurochemical in relation to headaches. Apparently contradictory results have been shown, such as increasing serotonin levels both increasing and decreasing headaches. Conclusions Serotonin plays an important role in the pathogenesis of headaches. Changes in serotonin may precede the vascular and muscular changes of migraine and tension-type headaches. The influence of serotonin on headaches explains a number of clinical situations that affect headache activity and the variety of classes of effective headache medications.
Applying Eigenvalue Perturbation Theory to Solve Problems in Structural Dynamics

In this paper the eigenvalue perturbation theory is applied to solve various problems in structural dynamics. Detailed derivations are presented along with examples to demonstrate the utility of the approach and its accuracy. In undergraduate classes on mechanical vibration, the eigenvalue perturbation theory is rarely taught, but it can be extremely valuable. The approach can be used to analyze the effects of design changes on the modes of vibration of a dynamical system, to determine the approximate eigensolutions of a nearly uniform continuous system, and to obtain the approximate complex eigencharacteristics of a lightly damped system. This paper shows that the eigenvalue perturbation theory can be easily introduced at the undergraduate level, because to understand the derivations only a first course in linear algebra is required, well within the capability of an undergraduate engineering student.
Relativistic and nuclear structure effects in parity-violating quasielastic electron scattering

The parity-violating longitudinal asymmetry [ital scrA] is calculated for quasielastic electron scattering. We use a varietry of relativistic mean field models for the response of nuclear matter and [sup 12]C at a momentum transfer of [ital q]=550 MeV/[ital c]. Relativistic effects from a reduced nucleon mass, RPA correlations, and vacuum polarization can all change [ital scrA] by a relatively large amount. These large nuclear structure corrections could make it impossible to extract strange quark matrix elements or radiative corrections to weak axial currents.
Inter-firm linkages, ethnic networks, and territorial agglomeration: Chinese computer firms in Los Angeles

Drawing from flexible production literature on industrial networks, this research pays particular attention to the socially embedded nature of firm linkages in a distribution sector. The empirical study of Chinese-owned computer wholesale firms within Los Angeles County shows that the presence of ethnic identity plays a significant role in the internal operation and external transactions of Chinese firms. Ethnic relations facilitate interactions within the ethnic group, producing a closely knit ethnic network within the industry. The heavy reliance on ethnic networks also has led Chinese firms to a notable geographical separation from the remaining firms in the same sector.
Isolation of polyribonucleotides using cellulose thin-layer plates.

Abstract A thin-layer chromatographic method is described for the rapid separation and isolation of polyribonucleotides after enzymatic polymerization. This method is particularly suitable for experiments in which several variables are to be compared. The polymers prepared by this method are in yield, molecular weight, melting temperature, and template and messenger activity comparable to those isolated by other methods.
S100B-Mediated Protection against the Pro-Apoptotic Effects of Ethanol On Fetal Rhombencephalic Neurons

Abstract Previously, this laboratory demonstrated that ethanol treatment significantly reduces the number of developing serotonin (5-HT) and other fetal rhombencephalic neurons in rats by augmenting apoptosis. Using a 5-HT 1A agonist we were able to attenuate the ethanol-associated reduction and apoptosis of 5-HT and rhombencephalic neurons. The downstream pro-survival effects of 5-HT 1A stimulation were associated with the activation of phosphatidylinositol 3′kinase (PI-3K) and its subsequent up-regulation of specific NF-κB-dependent pro-survival genes. Using an in vitro model, we investigated the hypothesis that S100B, a protein which is released from astrocytes following 5-HT 1A agonist stimulation, can reduce apoptosis in ethanol-treated rat fetal rhombencephalic neurons. We also evaluated whether the anti-apoptotic effects of S100B on fetal rhombencephalic neurons were linked to the activation of the PI-3K → pAkt pro-survival pathway and the expression of two NF-κB-dependent pro-survival genes: XIAP and Bcl-2. Moreover, we determined whether S100B's pro-survival effects were associated with mitogen activated protein kinase kinase (MAPKK) → p42/p44 MAPK. The results of these investigations demonstrated that S100B treatment prevented ethanol-associated apoptosis of fetal rhombencephalic neurons. In addition, it appears that these neuroprotective effects are linked to activation of the PI-3K pathways, because the PI-3K inhibitor LY294002 blocks the neuroprotective effects of S100B. Moreover, S100B increases the formation of pAkt and the up-regulation of two downstream NF-κB-dependent pro-survival genes: XIAP and Bcl-2. Although the MAPKK inhibitor PD98059 reduced the number of surviving neurons in S100B-treated cultures, S100B did not activate MAPKK.
Postnatal development and specification of the cat's visual corticotectal projection: efferent from the posteromedial lateral suprasylvian area

Abstract The corticotectal projection in adult cats has a precise topographic and laminar organization. Yet this projection initially grows beyond these adult targets. To begin to understand how the growing cortical axons achieve this precision, the morphological development of axons growing from the posteromedial lateral suprasylvian area (PMLS) to the superior colliculus was studied by injecting the anterograde tracer biocytin into the PMLS of cats between postnatal day (PO) and adulthood. The labeling patterns showed that (1) axons grow independently towards the colliculus and (2) the first axons from the PMLS arrive in the colliculus by P1 and continue to arrive over several days. Labeled growth cones were seen within the colliculus up to P15. (3) After reaching the colliculus, the axons undergo several morphological changes. Initially, they are unbranched and beaded, then short side branches are formed and finally extensive arborizations appear. Comparing the timing of these events with results from electron microscopic27 and electrophysiological46 studies that the appearance and increase in labeled axons with short side brances roughly coincides with the appearance and increase in number of synapses in the colliculus, whereas the elaboration of extensive arbors (and hence a corresponding increase in synapses) is well underway before visual influences on the colliculus can be measured. Thick sinuous axons are also labeled during maturation, usually in areas of the colliculus where they would be considered exuberant and may represent degenerating axons. (4) A coarse topography develops as the axons grow into the colliculus and becomes more precise in the following weeks. Initially, some axons extend well beyond their correct terminal zone, growing into the contralateral colliculus, caudally into the inferior colliculus and reaching all laminae of the ipsilateral superior colliculus. Similar targeting ‘errors’ have been reported during the growth of retinotectal axons, suggesting that cortical, retinal and perhaps other sources as well, may use the same extracellular cues to establish an initial coarse topography within the colliculus.
Countertrade: Forms, motives, pitfalls, and negotiation requisites

Abstract The impressive growth in countertrade necessitates a careful look at this trade financing mechanism and a new attitude by American policy makers and businessmen toward it. This study looks at the various forms of countertrade, at the motivating forces behind it, at the pitfalls that countertrade could engender, and at some imperatives in the negotiation of countertrade deals. The issues are examined from the perspective of a policy maker and that of a businessman. The two perspective are distinct but overlap sufficiently to merit a joint examination. It is the conclusion of this study that countertrade is here to stay, and that American businessmen better learn to cope with it if they are to maintain and improve their competitiveness in the world markets.
Control of the structural fidelity of microtubules by initiation sites.

The microtubules in most cells have 13 protofilaments. We show here that microtubules in pig brain also have 13 protofilaments. However, microtubules self-assembled in vitro from pig brain microtubule protein have a distribution of protofilament numbers other than 13. We have undertaken to determine whether the number of protofilaments is controlled by nucleation sites or by some intrinsic property of the structural protein which is lost during purification. We have counted the protofilaments of self-assembled microtubules and those of microtubules grown on stable seeds of known protofilament number. We have used the tannic acid staining method and electron microscopy of thin sections to visualize the protofilaments. Self-assembly of four-times cycled pig brain microtubule protein resulted in large numbers of 14-protofilament microtubules and smaller numbers of microtubules with fewer and more protofilaments. The same protein, when centrifuged at high speed to suppress self-nucleation, and seeded by axonemes of Chlamydomonas flagella, polymerized into microtubules with a restricted protofilament number distribution. When a low concentration of brain microtubule protein was used, favoring extension of only the A subfibers of the flagellar axonemes, nearly all of the microtubules nucleated had 13 protofilaments. However, when we used a higher concentration of microtubule protein, both the A and B subfibers were extended, giving rise to 13 and 14-protofilament microtubules. We conclude that control of the structural fidelity of microtubules assembled in vitro resides in the nucleation sites and is not an intrinsic property of purified microtubule protein. The seed-directed polymerization reaction described here represents the first in vitro system that reconstitutes microtubules with fidelity.
Quantized Einstein–Rosen waves, AdS2, and spontaneous symmetry breaking

Abstract 4D cylindrical gravitational waves with aligned polarizations (Einstein–Rosen waves) are shown to be described by a weight 1/2 massive free field on the double cover of AdS2. Thorn's C-energy is one of the sl(2, R ) generators, the reconstruction from the (timelike) symmetry axis is the CFT1 holography. Classically the phase space is also invariant under a O(1,1) group action on the metric coefficients that is a remnant of the original 4D diffeomorphism invariance. In the quantum theory this symmetry is found to be spontaneously broken while the AdS2 conformal invariance remains intact.
Development of photochemical method for meniscal repair: A preliminary study

Visible light combined with naphthalimides has previously been shown to catalyze formation of physical bonds in avascular meniscal tissue. The first objective was to modify the existing in vitro testing method (i.e., adhesion testing using lap-jointed slices) to gain more sensitivity in detecting relative bonding strengths among candidate bonding agents. A repeated measures experimental design (RMED) was used to account for variability in properties among bovine menisci and was achieved by testing all treatments/controls on slices from each meniscus. Additionally, to make the method more clinically relevant in modeling a bucket-handle tear, the bovine meniscal slices were cut with collagen fibers parallel to the test slice's length. Peak stress was greater for the complete treatment group (light plus naphthalimide) than for the control or incomplete treatment groups (light only or napthalimide only). The second objective was to perform concentration and photoactivation time dose-response studies. In the concentration dose-response study, peak stress was greater for all treatments when compared with the control but not different among treatment groups; however, there was a trend of increased bonding strength with increased concentration. In the photoactivation time dose-response study, peak stress was greater for all treatments when compared with the control and greater for the 3-min treatment vs. the 6- and 9-min treatments. Peak stress was not different between the longer treatments. The RMED provided increased reproducibility and statistical sensitivity for detecting differences among treatments and will be used to test candidate bonding agents prior to in vivo testing.
Stochastic series expansion algorithm for the S = 1/2 XY model with four-site ring exchange.

We describe a stochastic series expansion quantum Monte Carlo method for a two-dimensional S = 1/2 XY model (or, equivalently, hard-core bosons at half filling) which in addition to the standard pair interaction J includes a four-site term K that flips spins on a square plaquette. The model has three ordered ground state phases; for K/J approximately or = 15 it has staggered spin order in the z direction (charge-density wave), and between these phases it is in a state with columnar order in the bond and plaquette energy densities. We discuss an implementation of directed-loop updates for the SSE simulations of this model and also introduce a "multibranch" cluster update which significantly reduces the autocorrelation times for large K/J. In addition to the pure J-K model, which in the z basis has only off-diagonal terms, we also discuss modifications of the algorithm needed when various diagonal interactions are included.
Role of Na+ and anions in the triple response of isolated frog skin to norepinephrine.

Abstract 1. 1. Isolated short-circuited frog skin in NaCl or NaHCO 3 solutions responded to norepinephrine (3–10 −5 M), added to the epithelial side, with an increase in short-circuit current (s.c.c.) and open-skin potential ( V ) with little if any change in total skin conductance ( G = s.c.c./ V ). Skins in Na 2 SO 4 solutions gave a greatly diminished response to norepinephrine added to the epithelial side, with indication of depression of s.c.c. and V later during the experiment. Thus, the response is dependent on Cl − or HCO 3 − . 2. 2. Omission of Na + from the solution at the epithelial side (arginine chloride (outside), NaCl (inside)) resulted in a very weak norepinephrine (outside) response, suggesting that norepinephrine (outside) stimulates active inward Na + transport. Skins in arginine sulfate (outside), NaCl (inside); choline bicarbonate (outside), sodium bicarbonate (inside); arginine sulfate (outside), sodium bicarbonate (inside) also failed to give the marked response noted in 1. 3. 3. When applied to the corium side, norepinephrine led to an increase in s.c.c. and G but a decrease in V by action on the glandular epithelium in the presence on the inside of NaCl or NaHCO 3 , regardless of the presence or absence of Na + on the epithelial side. Flux measurements proved that active outward Cl − transport occurred. Active outward HCO 3 − transport, suggested by the s.c.c. results, was unmeasurably small because of a 100 times greater C flux in the form of CO 2 which was equal in both directions and unaffected by norepinephrine on the corium side. Active outward Cl − transport was greatly depressed when Na + on the corium side was replaced by arginine + . There was good recovery of V and s.c.c. when NaCl solutions were present on both sides. 4. 4. Ouabain (5·10 −4 M), or propranolol (5·10 −5 M) greatly decreased active glandular Cl − transport following application of norepinephrine to the corium side. Diamox (5·10 −3 M) had a small depressing effect of norepinephrine (inside) on Cl − transport, and it depressed completely a relatively weak norepinephrine (inside) response, presumably because of a decrease in HCO 3 − transport. 5. 5. The results are interpreted as showing functional dependency of α-inhibitory and β-stimulatory adrenergic receptor sites in frog skin epidermis on the nature of the anion present (SO 4 2 vs Cl − and HCO 3 − ), and of β-stimulatory receptor sites in the glandular epithelium on the presence of Na + .
Creep properties of an extruded copper–8% chromium–4% niobium alloy

Constant-stress creep experiments were conducted on extruded Cu–8 Cr–4 Nb (GRCop-84) from 0.57 to 0.79 Tm, with observed strain rates spanning over four orders of magnitude. GRCop-84 is composed of approximately 14 vol.% Cr2Nb distributed in sizes ranging from approximately 30 nm to 0.5m in a matrix of pure copper with a grain size of approximately 1–3m. This high-strength alloy exhibits creep curves with a standard pure metal-type appearance and true failure strains typically in excess of 10%. The Monkman–Grant relationship is obeyed with a slope of −1.08. Computation of activation energies between neighboring isotherms yields an average value of 287 ± 14 kJ/mol. Despite apparent power law creep behavior within an isotherm, a master plot of temperature compensated strain rate ( ˙/exp[−Q/RT]) versus temperature compensated stress (σ/G) demonstrates that most of the data are above power law breakdown, consistent with σ/G ˜
Role of Whole Foods in Promoting Hydration after Exercise in Humans

Various reports indicate that humans receive 20-25% of their daily water intake from food. Fruits, vegetables and other high-moisture foods, therefore, make an important contribution to total fluid intake. In addition, co-ingestion of other nutrients and ingredients can impact drinking behavior, absorption, distribution and retention of water, all of which contribute to the person's hydration state. Therefore, a food's hydration value derives from the interaction between its water content and the presence of these co-nutrients and ingredients. Research is reviewed in this paper showing increased voluntary fluid intake of young boys during exercise when the beverage is flavored and contains sodium chloride and carbohydrate. Additional research on rehydration after exercise and heat exposure showed improved recovery of plasma volume and fluid status when food was ingested before consuming water in the two hours after exercise. Collectively, these findings point to an interaction between fluid intake and co-ingested nutrients in regulating human hydration during and after exercise.
Clinical Research and Patient-rated Outcome Measures in Hand Surgery

High-quality clinical research incorporating standardized outcome assessments is necessary to advance the field of hand surgery. Although such research can be conducted with little direct cost, effectively answering clinical questions requires thoughtful study design. Relevant concepts to consider include sample size determination, study end points, data management, and choice of outcome measures. Provided the emphasis on, and proliferation of, patient-rated outcome measures, the clinician-researcher should consider the unique aspects of commonly referenced outcome measures when initiating an investigation.
Burst switching for third generation wireless communications

There has been extensive research on integrating multimedia capabilities into mobile communications. One of the key issues is the efficient allocation of radio and network resources for multimedia applications that exhibit bursty traffic with fractal dimensions. This paper investigates burst switching technique for channel allocation of aggregate bursty traffic in a slotted CDMA system. The burst switching technique utilizes an optimal timer that releases the channel when an idle time begins. Hence, the dedicated channels are allocated for the duration of the burst of data so that the allocation delay is decreased while channel utilization is increased.
Youth in Foster Care With Adult Mentors During Adolescence Have Improved Adult Outcomes

OBJECTIVE. The goal of this study was to determine whether youth in foster care with natural mentors during adolescence have improved young adult outcomes. METHODS. We used data from waves I to III of the National Longitudinal Study of Adolescent Health (1994 –2002). Individuals who reported that they had ever been in foster care at wave III were included. Youth were considered mentored when they reported the presence of a nonparental adult mentor in their life after they were 14 years of age and reported that the relationship began before 18 years of age and had lasted for at least 2 years. Outcomes were assessed at wave III and included measures of education/employment, psychological well-being, physical health, and participation in unhealthy behaviors as well as a summary measure representing the total number of positive outcomes. RESULTS. A total of 310 youth met the inclusion criteria; 160 youth were mentored, and 150 youth were nonmentored. Demographic characteristics were similar for mentored and nonmentored youth. Mentored youth were more likely to report favorable overall health and were less likely to report suicidal ideation, having received a diagnosis of a sexually transmitted infection, and having hurt someone in a fight in the past year. There was also a borderline significant trend toward more participation in higher education among mentored youth. On the summary measure, mentored youth had, on average, a significantly greater number of positive outcomes than nonmentored youth. CONCLUSIONS. Mentoring relationships are associated with positive adjustment during the transition to adulthood for youth in foster care. Strategies to support natural mentoring relationships for this population should be developed and evaluated.
Fear of novelty in infant rats predicts adult corticosterone dynamics and an early death

Individuals who are fearful of novelty have a larger hypothalamic– pituitary–adrenal axis response than do nonfearful individuals. We hypothesized that a fearful behavioral style emerging early in life would be associated with life-long altered adrenal activity. Because there is ample physiological evidence both costs and benefits of adrenal activation, we determined whether such a stable emotional–neuroendocrine trait was associated with differential morbidity and mortality. To conduct such lifespan work, we studied a relatively short-lived mammal: the Norway rat. We first established that an animal’s hesitation or willingness to explore a novel environment (‘‘neophobia’’ and ‘‘neophilia,’’ respectively) is an identifiable and stable behavioral trait in young-adult males and that neophobia, compared with neophilia, was associated with a greater glucocorticoid response to novelty. Second, we were able to detect behavioral differences among infant rats within a family, and this behavioral disposition at infancy predicted the magnitude of the glucocorticoid response in late middle age. Males identified as neophobic during infancy died sooner than their less fearful brothers. Although both types of males died with similar pathologies (tumors), neophobic males were 60% more likely to die at any point in time. This lifespan study identifies an emotional trait in infancy that predicts an early death and an associated neuroendocrine trait in adulthood that is a potential mechanism underlying the relationship between behavioral style and longevity.
Clinical and Prognostic Implications of Plasma Insulin-Like Growth Factor-1 and Vascular Endothelial Growth Factor in Patients With Hepatocellular Carcinoma

Purpose Cirrhosis and hepatocellular carcinoma (HCC) together form a two-disease state that affects survival of patients with HCC and dictates treatment decisions and prognostic stratification of patients in clinical trials. The study objective was to improve prognostic stratification of patients with HCC. Patients and Methods We prospectively collected plasma samples and baseline clinicopathologic features from 288 new patients with HCC, and plasma insulin-like growth factor-1 (IGF-1) and vascular endothelial growth factor (VEGF) levels were tested. We applied Cox regression and log-rank tests to assess association of IGF-1 and VEGF with overall survival (OS), Kaplan-Meier curves to estimate OS, and recursive partitioning to determine optimal cutoff points for IGF-1 and VEGF. Prognostic ability of conventional and molecular Barcelona Clinic Liver Cancer classifications was compared using the c-index. Results Lower plasma IGF-1 and higher plasma VEGF levels significantly correlated with advanced clinicopa...
Effect of Androgens on the Red Cell 2, 3 Diphosphoglycerate Hemoglobin Oxygen Affinity and Red Cell Mass in Mammals

SummaryThe effect of androgens on the RCM in the squirrel monkey and the RBC 2,3 DPG and hemoglobin oxygen affinity in the squirrel monkey and in mice was studied. It was found that administration of 19-ND resulted in an increase in RCM, and elevation of the RBC 2,3 DPG and a “right shift” of the oxygen hemoglobin equilibrium curve. The possible relationship of these phenomena is discussed. It is suggested that the increase in RBC 2,3 DPG is not a result of a direct effect of the androgen on the metabolism of the RBC.
Reperfusion injury, microvascular dysfunction, and cardioprotection: The "dark side" of reperfusion

Early restoration of coronary perfusion is the single most important objective in the management of ST-segment elevation myocardial infarction (STEMI). Failure to do so is associated with larger myocardial infarcts and a greater likelihood of ventricular arrhythmias, cardiac failure, cardiogenic shock, and death.1 Thus, the immediate goal of reperfusion therapy is to restore normal epicardial blood flow promptly, which is achieved most effectively with primary percutaneous coronary intervention (PCI).2,3 Advances in adjunctive interventional techniques and pharmacological therapy have made it possible to achieve normal (Thrombolysis in Myocardial Infarction grade 3 flow) epicardial flow in as many as 95% of patients undergoing primary PCI.2 Nevertheless, despite timely reperfusion of the infarct-related artery and the establishment of a patent epicardial coronary vessel, restoring optimal myocardial (microvascular) perfusion and salvage in all patients has remained elusive, representing perhaps the last frontier of reperfusion therapy.3 Potential mechanisms that may limit myocardial salvage include microvascular dysfunction and lethal reperfusion injury (RI). The entity of microvascular dysfunction is well documented clinically and thought to be the consequence of ≥1 of the following: distal coronary emboli resulting from thrombus, platelets and atheroma, in situ thrombosis, vasospasm, and/or inflammation.4 RI, as it relates to the heart, may be defined as myocardial and vascular injury occurring as a direct result of blood flow restoration to the ischemic tissue.5 It is proposed that the resulting cellular dysfunction, apoptosis, and necrosis mediate myocardial stunning, no reflow, reperfusion arrhythmias, and additional loss of myocardium (lethal RI).6 The precise pathophysiology of RI remains to be established, although several mechanisms have been proposed (Figure 1).6 The current understanding of the etiology of RI is derived predominantly from animal studies in which interventions that inhibit the putative mediators of RI have been shown to reduce infarct …
Impacts of coffee agroforestry management on tropical bee communities.

Though it is undoubted that tropical bees are influenced by habitat composition, few studies have investigated the relative importance of both local and landscape-level habitat parameters in supporting large and diverse bee communities. The conservation of native bee communities within agroforestry landscapes is particularly urgent given the importance of pollination services within these systems. In this study, we examined tropical bee communities within a largely deforested shade coffee-growing region in Chiapas, Mexico. We used regression tree modeling to examine the response of bee functional groups to local and landscape-level habitat management. Our models revealed that the most predictive factors for bee abundance and species richness were the number of tree species, the number of tree species in flower, and the canopy cover of the local agroforestry landscape. Solitary bees were most abundant in habitats with high canopy cover, while social bees were most abundant in habitats with greater tree species richness. Cavity-nesting and wood-nesting bee abundance was positively affected by the amount of canopy cover in the farm, while ground-nesting bees were most abundant in habitats with a large number of tree species in flower. Our results demonstrate that across bee sociality groups, nesting guilds, and tribes, the most critical factor impacting native bee communities was within-farm local vegetation management. These results reveal the important role that agroforestry managers can have on biodiversity conservation, and the potential contribution they can make by creating resource-rich agricultural matrices. Specifically, our findings highlight the importance of diverse overstory tree management in supporting native bee communities within tropical agroforestry systems.
Insulin signaling in fatty acid and fat synthesis: a transcriptional perspective

Transcription of enzymes involved in FA and TAG synthesis is coordinately induced in lipogenic tissues by feeding and insulin treatment. The three major transcription factors involved are USF, SREBP-1c, and LXRα. New insights into the insulin-signaling pathway(s) that control(s) lipogenic gene transcription via these factors have recently been revealed. Dephosphorylation/activation of DNA-PK by PP1 causes phosphorylation of USF that in turn recruits P/CAF to be acetylated for transcriptional activation. SREBP-1c can be induced by mTORC1, bifurcating lipogenesis from AKT-activated gluconeogenesis. LXRα may serve as a glucose sensor and, along with ChREBP, may activate lipogenic genes in the fed state. Dysregulation of FA and TAG metabolism often contributes to metabolic diseases such as obesity, diabetes, and cardiovascular diseases. Transcription factors and signaling molecules involved in transcriptional activation of FA and TAG synthesis represent attractive targets for the prevention and treatment of metabolic diseases.
Right on target: eradicating leukemic stem cells

Less than a third of adults with acute myeloid leukemia (AML) are cured by current treatments, emphasizing the need for new approaches to therapy. The discovery over a decade ago that myeloid leukemias originate from rare stem-like cells that can transfer the disease to immunodeficient mice suggested that these 'leukemia stem cells' (LSCs) are responsible for relapse of leukemia following conventional or targeted cancer therapy and that eradication of LSCs might be necessary to cure the disease permanently. Several recent studies have provided insight into the signaling pathways underlying the LSC phenotype and have also described approaches to eliminate LSCs with antibodies. Here, we review recent advances in LSC research and discuss novel therapeutic strategies to specifically target LSCs.
Palliative stent placement in vertical vein in a 1.4 kg infant with obstructed supracardiac total anomalous pulmonary venous connection.

Temporary relief of obstructed total anomalous pulmonary venous connection (TAPVC) may stabilize the preoperative clinical status. We report a 1.4 kg infant with obstructed supracardiac TAPVC to right sided superior vena cava, double outlet right ventricle, pulmonary atresia, major aortopulmonary collateral arteries, and atrioventricular septal defect. A palliative percutaneous stent was successfully placed and resulted in immediate clinical improvement. We performed a review of literature regarding interventional procedures for relief of obstructed TAPVC and found 17 cases including stent placement (13), balloon angioplasty (3), and Hybrid procedure (1). We conclude that temporary stent placement in obstructed TAPVC is feasible and efficacious in relieving pulmonary venous obstruction. The procedure can lead to subsequent surgical repair in a more favorable clinical status and has special significance in the low birth weight infant. © 2012 Wiley Periodicals, Inc.
A Typology for Understanding the Connections Among Different Forms of Social Capital

Critics have argued that the term social capital is too vague or general to be a useful concept. Recognizing the need for clarification, the authors distill the conceptual discussions about social capital to argue that there are three components_network structure, trust and reciprocity, and resources_that are associated with but vary in degree and salience for all forms of social capital. These three components should be considered continua along which the forms of social capital can vary. A fourth continuum is between micro and macro levels of social capital. Locating particular examples of social capital along these continua opens the possibility to compare different types of social capital and to develop and test theories about how they are related to each other. The authors also describe a simulation study to illustrate how simulation can facilitate understanding of the linkages among different forms of social capital.
A logistic model for the prediction of endometriosis

Objective To develop a model that uses individual and lesion characteristics to help surgeons choose lesions that have a high probability of containing histologically confirmed endometriosis. Design Secondary analysis of prospectively collected information. Setting Government research hospital in the United States. Patient(s) Healthy women 18–45 years of age, with chronic pelvic pain and possible endometriosis, who were enrolled in a clinical trial. Intervention(s) All participants underwent laparoscopy, and information was collected on all visible lesions. Lesion data were randomly allocated to a training and test data set. Main Outcome Measure(s) Predictive logistic regression, with the outcome of interest being histologic diagnosis of endometriosis. Result(s) After validation, the model was applied to the complete data set, with a sensitivity of 88.4% and specificity of 24.6%. The positive predictive value was 69.2%, and the negative predictive value was 53.3%, equating to correct classification of a lesion of 66.5%. Mixed color; larger width; and location in the ovarian fossa, colon, or appendix were most strongly associated with the presence of endometriosis. Conclusion(s) This model identified characteristics that indicate high and low probabilities of biopsy-proven endometriosis. It is useful as a guide in choosing appropriate lesions for biopsy, but the improvement using the model is not great enough to replace histologic confirmation of endometriosis.
Guiding Threat Analysis with Threat Source Models

Threat analysis identifies how potential adversaries exploit system weaknesses to achieve their goals. Attack graphs are one method to conduct threat analysis by exposing vulnerability relationships, allowing administrators to pinpoint high risk paths. However, computational and cognitive complexity challenges must be dealt with. One method for managing threat analysis and attack graph complexity is to differentiate between likely and unlikely attack paths using threat source models. Threat source models are used during risk assessments to describe likely and unlikely adversary behavior, and so can be used for the same purpose during attack graph analysis. The framework presented here allows threat source models to guide attack graph generation to remove unlikely attack paths.
Lung cancer imaging

Lung cancer remains the leading cause of cancer-related deaths in the US. Imaging plays an important role in the diagnosis, staging, and follow-up evaluation of patients with lung cancer. With recent advances in technology, it is important to update and standardize the radiological practices in lung cancer evaluation. In this article, the authors review the main clinical applications of different imaging modalities and the most common radiological presentations of lung cancer.
Update on bevacizumab and other angiogenesis inhibitors for brain cancer.

Introduction: Primary and metastatic brain tumors remain a major challenge. The most common primary adult malignant brain tumor, glioblastoma (GBM), confers a dismal prognosis as does the development of CNS metastases for most systemic malignancies. Anti-angiogenic therapy has been a major clinical research focus in neuro-oncology over the past 5 years. Areas covered: Culmination of this work includes US FDA accelerated approval of bevacizumab for recurrent GBM and the completion of two placebo-controlled Phase III studies of bevacizumab for newly diagnosed GBM. A multitude of anti-angiogenics are in evaluation for neuro-oncology patients but none has thus far surpassed the therapeutic benefit of bevacizumab. Expert opinion: These agents demonstrate adequate safety and the majority of GBM patients derive benefit. Furthermore, their anti-permeability effect can substantially decrease tumor-associated edema leading to stable or improved neurologic function and quality of life. In particular, anti-angiogenic...
The House that Traces Built: A Conceptual Model of Service Delivery Systems and Implications for Change:

A growing emphasis on effecting systems change in the education of individuals with severe disabilities poses many challenges. Although the depth and breadth of knowledge on effective change strategies is considerable, comparatively little has been written that functionally weds this knowledge base to an adequate conception of systems. This article develops a framework for a common definition of system and system change, which currently is lacking in the literature. The framework draws heavily from current understandings within chaos theory, quantum physics, and self-ordering systems about how naturally occurring systems operate. The framework provides the flexibility to be applied to various systems, while at the same time approaching the understanding and change of these systems with consistency.
On the Margins of Marginalized: Transgender Homelessness and Survival Sex

Transgender and gender-nonconforming (GNC) individuals experience homelessness at higher rates compared to the broader population, with many directly attributing homelessness to their transgender/GNC identities. Homeless individuals often engage in survival sex in exchange for food, housing, and other basic necessities. Few research efforts, however, have examined survival sex specifically among homeless transgender/GNC populations. Utilizing the 2011 National Transgender Discrimination Survey (N = 6,454), this exploratory study analyzes relationships between homelessness and survival sex among transgender/GNC individuals. Results suggest these individuals experience homelessness at high rates, and their engagement in survival sex is associated with homelessness. Implications for social work are subsequently discussed.
AR-V7 Protein in Circulating Tumor Cells-The Decider for Therapy?

In this issue of JAMA Oncology, Scher et al 1 present additional evidence that the presence of the constitutively active androgen receptor variant 7 (AR-V7) is a marker for resistance to standard androgen deprivation or second line androgen receptor (AR) targeting agents in men with metastatic prostate cancer. Blood samples were drawn prior to therapy and nucleated cells analyzed for protein expression by immunofluorescence for AR-V7 protein. Results were not used for clinical decision making. Remarkably, no patients with circulating tumor cells (CTCs) positive for AR-V7 protein responded to AR-directed therapy (as defined by a >50% prostate-specific antigen decline), and they had significantly worse progression-free survival and overall survival (OS) compared with patients with AR-V7– negative CTCs. These findings are in agreement with those previously reported by Antonorakis et al 2 using a different messenger RNA (mRNA)-based CTC assay. 2 These 2 studies provide compelling evidence that AR-V7–positive CTCs are a predictive biomarker for failure to respond to AR-directed therapy (AR-DT). The studies by Scher et al 1 and Antonorakis et al 2 differ in several respects. First, there was a lower proportion of patients with AR-V7–positive CTCs at each line of therapy using the protein-based assay compared with the mRNAbased assay. Although the patient groups were not entirely identical, this difference in detection may reflect greater sensitivity provided by polymerase chain reaction (PCR) vs antibody detection systems. Second, the issues of specificity of antibodies vs PCR are clearly different. Work has been presented showing that AR-V7 antibodies can react with nonprostate tissue and cell lines such as PC-3, in which no AR-V7 message or N-terminal AR protein c an be identified. 3 In the study by Scher et al, AR-V7 immunofluorescence was identified in CTCs that were cytokeratin negative or where other presumed CTCs in the sample were negative for AR N-terminal staining that should detect AR-V7. Although relevant in only a small fraction of the patient samples, appropriate prospective and interinstitutional correlative studies should be done to confirm sensitivity and specificity of the assay before the current test can be applied broadly.
What did we learn by studying scleroderma fibroblasts

Systemic sclerosis (SSc, scleroderma) is a complex disease manifesting itself by fibrosis of skin and other internal organs. Fibroblasts isolated from SSc lesions and cultured in vitro are characterized by the increased synthesis of collagen and other extracellular matrix (ECM) proteins, consistent with the disease phenotype. Cultured SSc fibroblasts therefore serve as a principal experimental model for studying the molecular and cellular mechanisms involved in collagen overproduction in this disease. This article provides an overview of transcription factors that are deregulated in SSc fibroblasts. The possible origin of SSc fibroblasts is also discussed.
ERG Immunohistochemical (IHC) Expression in Fibrohistiocytic Tumors: A Diagnostic Pitfall

ERG (known vascular endothelial marker) IHC expression has been previously described in prostatic adenocarcinoma, acute myeloid leukemia, and Ewing sarcoma/PNET, but not been well studied in histiocytic tumors. Having anecdotally seen ERG expression in histiocytic tumors, the aim of this study was to evaluate ERG expression in giant cell tumor of tendon sheath (GCT) and benign fibrous histiocytoma (BFH). ERG, …