cssi/SciSciGPT-SciSciNet huggingface dataset:
Structure of the Calcineurin-NFAT Complex: Defining a T Cell Activation Switch Using Solution NMR and Crystal Coordinates

Summary Calcineurin (Cn) is a serine/threonine protein phosphatase that plays pivotal roles in many physiological processes, including cell proliferation, development, and apoptosis. Most prominently, Cn targets the nuclear factors of activated T cell (NFATs), transcription factors that activate cytokine genes. Calcium-activated Cn dephosphorylates multiple residues within the regulatory domain of NFAT, triggering joint nuclear translocation. This relies crucially on the interaction between the catalytic domain of Cn (CnCat) and the conserved PxIxIT motif located in a region distinct from the dephosphorylation sites of NFAT. Here, we present the structure of the complex between the 39 kDa CnCat and a 14 residue peptide containing a PVIVIT segment that was derived from affinity-driven peptide selection based on the conserved PxIxIT motif of NFATs. The structure of the complex was determined by using NMR assignments and structural constraints and the coordinates of the CnCat crystal structure. The NMR analysis relied on recently developed labeling and spectroscopic techniques. The VIVIT peptide is accommodated in a hydrophobic cleft formed by β strands 11 and 14, and the loop between β strands 11 and 12, forming a short parallel β sheet with the exposed β strand 14 in Cn. The side chains of conserved residues in the PxIxIT sequences make extensive interactions with conserved residues in Cn, while those of nonconserved residues are solvent exposed. The architecture of the interface explains the diversity of recognition sequences compatible with NFAT function and uncovers a potential targeting site for immune-suppressive agents. The structure reveals that the orientation of the bound PxIxIT directs the phosphorylation sites in NFAT's regulatory domain toward the Cn catalytic site.
St. John's Wort inhibits insulin signaling in murine and human adipocytes

Adipocytes are insulin-sensitive cells that play a major role in energy homeostasis. Obesity is the primary disease of fat cells and a major risk factor for the development of Type 2 diabetes, cardiovascular disease, and metabolic syndrome. The use of botanicals in the treatment of metabolic diseases is an emerging area of research. In previous studies, we screened over 425 botanical extracts for their ability to modulate adipogenesis and insulin sensitivity. We identified St. John's Wort (SJW) extracts as inhibitors of adipogenesis of 3T3-L1 cells and demonstrated that these extracts also inhibited insulin-sensitive glucose uptake in mature fat cells. In these follow-up studies we have further characterized the effects of SJW on insulin action in both murine and human fat cells. We have shown that SJW also attenuates insulin-sensitive glucose uptake in human adipocytes. Moreover, SJW inhibits IRS-1 tyrosine phosphorylation in both murine and human fat cells. Botanical extracts are complex mixtures. Many bioactive compounds have been identified in SJW, including hypericin (HI) and hyperforin (HF). We have examined the ability of HI and HF, purified from SJW, to modulate adipocyte development and insulin action in mature adipocytes. Our novel studies indicate that the profound effects of SJW on adipogenesis, IRS-1 activation, and insulin-stimulated glucose uptake are not mediated by HI and/or HF. Nonetheless, we propose that extracts of SJW may contribute to adipocyte related diseases by limiting differentiation of preadipocytes and significantly inducing insulin resistance in mature fat cells.
Δ12-prostaglandin J3, an omega-3 fatty acid-derived metabolite, selectively ablates leukemia stem cells in mice

Targeting cancer stem cells is of paramount importance in successfully preventing cancer relapse. Recently, in silico screening of public gene-expression datasets identified cyclooxygenase-derived cyclopentenone prostaglandins (CyPGs) as likely agents to target malignant stem cells. We show here that Δ12-PGJ3, a novel and naturally produced CyPG from the dietary fish-oil ω-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA; 20:5) alleviates the development of leukemia in 2 well-studied murine models of leukemia. IP administration of Δ12-PGJ3 to mice infected with Friend erythroleukemia virus or those expressing the chronic myelogenous leukemia oncoprotein BCR-ABL in the hematopoietic stem cell pool completely restored normal hematologic parameters, splenic histology, and enhanced survival. More importantly, Δ12-PGJ3 selectively targeted leukemia stem cells (LSCs) for apoptosis in the spleen and BM. This treatment completely eradicated LSCs in vivo, as demonstrated by the inability of donor cells from treated mice to cause leukemia in secondary transplantations. Given the potency of ω-3 polyunsaturated fatty acid–derived CyPGs and the well-known refractoriness of LSCs to currently used clinical agents, Δ12-PGJ3 may represent a new chemotherapeutic for leukemia that targets LSCs.
Learning word meanings and descriptive parameter spaces from music

The audio bitstream in music encodes a high amount of statistical, acoustic, emotional and cultural information. But music also has an important linguistic accessory; most musical artists are described in great detail in record reviews, fan sites and news items. We highlight current and ongoing research into extracting relevant features from audio and simultaneously learning language features linked to the music. We show results in a "query-by-description" task in which we learn the perceptual meaning of automatically-discovered single-term descriptive components, as well as a method of automatically uncovering 'semantically attached' terms (terms that have perceptual grounding.) We then show recent work in 'semantic basis functions' --- parameter spaces of description (such as fast ... slow or male ... female) that encode the highest descriptive variance in a semantic space.
Effects of a group-based exercise program on the physical performance, muscle strength and quality of life in older women.

This study was aimed at determining the effect of a group-based exercise program on the physical performance, muscle strength and quality of life (QoL) in older women. Twenty women performed an exercise program for 8 weeks, at the rehabilitation unit. Outcome measures included a 4-m and 20-m walk test, a 6-min walk test, stair climbing and chair rise time, timed up and go test, isokinetic muscle testing of the knee and ankle, and the short form-36 (SF-36) and geriatric depression scale (GDS) questionnaires. The mean age of the study group was 70.3 ± 6.5 years. After the completion of the exercise program, all of the physical performance tests and the SF-36 scores for the participants showed statistically significant improvements (p < 0.05). In the isokinetic evaluations, most of angular velocities showed a significant increase in the peak torque (PT) values for knee extension and flexion, and for ankle plantar flexion (p < 0.05). We concluded that this exercise program, when applied to older women, resulted in improved physical performance, increased muscle strength measured in both the knee and ankle, and improvement in the scores, estimating the QoL. We have shown that this exercise program is both effective and reliable for this age group of women.
A new spectral test for nonrandomness and the DES

A test for detecting the nonrandomness of finite binary strings is proposed. This test, based on an evaluation of the power spectrum of a finite string, extends and quantifies a similar test proposed by J. Gait (see ibid., vol.3, no.5, p.359-63, 1977). As an empirical measure of the sensitivity of the test, it was compared with a chi-square test for uniformity of distribution, which also measures nonrandomness. This comparison was performed by applying each of these tests to binary strings produced using short-round versions of the data encryption standard (DES) in output-feedback mode. By varying the number of DES rounds from 1 to 16, it was possible to gradually vary the degree of randomness of the resulting strings. The degree of randomness of the DES, including the 15 short-round versions, was also assessed. Only ensembles generated by one and two round versions were rejected as random. >
Direct binding of progesterone receptor to nonconsensus DNA sequences represses rat GnRH

Abstract The mechanisms by which steroid receptors repress gene expression are not well understood. In this report, we show that progesterone receptor (PR), in the presence of progesterone (P) directly represses rat gonadotropin releasing hormone (rGnRH) gene transcription. Deletion analysis studies using transient transfection assays in GT1–7 neuronal cells mapped the effects of P to sequences in the proximal rGnRH promoter between −171 and −73. This DNA sequence lacks any consensus steroid response element binding sites. Cotransfection of a mutant progesterone receptor that lacks a functional DNA binding region (hPRcys) abolished repression of the rGnRH promoter by P. Gel mobility shift assays confirmed that PR directly binds to the DNA fragments −171 −126 , −126 −73 , and −111 −73 , which encompass the negative progesterone response element (nPRE) of the rGnRH promoter. Mutagenesis of the rGnRH nPRE −171 −126 DNA fragment resulted in a loss of PR binding. Thus, direct DNA binding of PR to nonconsensus elements in the proximal rGnRH promoter inhibits rGnRH gene expression.
Photochemistry of N-Hydroxy-2(1H)-pyridone, a More Selective Source of Hydroxyl Radicals Than N-Hydroxypyridine-2(1H)-thione

The primary and subsequent photochemistry of N-hydroxy-2(1H)-pyridone (N-HP) has been investigated in aqueous and nonaqueous media by laser flash photolysis (λexc = 308 nm). In organic solvents, as well as in buffers at pH ≤ 7, the initial photochemistry of N-HP consists of homolytic N−O bond cleavage leading to the formation of the 2-pyridyloxyl (PyO•) and hydroxyl (•OH) radicals, the quantum yield (ΦN-O = Φ•OH) varying from 0.25 to 0.6, depending on the solvent. Quenching experiments have demonstrated that PyO• is relatively unreactive and is removed mainly via a bimolecular radical reaction. In highly basic aqueous media, N-HP exists in the anionic form and is much less photolabile. At pH = 10, in addition to a low yield of N−O bond cleavage (ΦN-O = 0.037), N-HP undergoes photoionization, but solvated electron production was found to be very inefficient (Φe- = 0.003). Thus, under biologically relevant conditions, N-HP has a much simpler photochemical behavior than that of the closely related N-hydroxyp...
Contribution of extracellular polymeric substances on representative gram negative and gram positive bacterial deposition in porous media.

The significance of extracellular polymeric substances (EPS) on cell transport and retained bacteria profiles in packed porous media (quartz sand) was examined by direct comparison of the overall deposition kinetics and retained profiles of untreated bacteria (with EPS) versus those of treated cells (without EPS) from the same cell type. Four representative cell types, Pseudomonas sp. QG6 (gram-negative, motile), mutant Escherichia coli BL21 (gram-negative, nonmotile), Bacillus subtilis (gram-positive, motile), and Rhodococcus sp. QL2 (gram-positive, nonmotile), were employed to systematically determine the influence of EPS on cell transport and deposition behavior. Packed column experiments were conducted for the untreated and treated cells in both NaCl (four ionic strength ranging from 2.5 mM to 20 mM) and CaCl2 (5 mM) solutions at pH 6.0. The breakthrough plateaus of untreated bacteria were lower than those of treated bacteria for all four cell types under all examined conditions (in both NaCl and CaCl...
Priapism in the United States: the changing role of sickle cell disease.

Abstract Background Few patients with priapism require inpatient management unless they are refractory to intracavernosal therapy. Their risk factors and outcomes are poorly characterized. Methods This is a retrospective analysis of the Nationwide Inpatient Sample (1998–2006). Priapism patients were identified and analyzed over time by age, race, sickle-cell disease diagnosis, drug abuse, and penile operations. Results A total of 4,237 hospitalizations for priapism were identified (30% white, 61.1% black, and 6.3% Hispanics). There was an increasing incidence of priapism over time, concentrated in the middle-age group. There were 1,776 patients (41.9%) with diagnoses of sickle-cell disease, with decreasing proportions over time. Drug abuse was reported in 7.9%. Conclusions Inpatient diagnoses of priapism are increasing over time with relatively constant numbers of sickle-cell disease patients, suggesting rising nonhematologic causes of priapism. One theory is that increasing use of aggressive therapies for erectile dysfunction might play a role, especially when combined with drug abuse.
Complication Rates Among Cancer Patients With Peripherally Inserted Central Catheters

PURPOSE: Peripherally inserted central catheters (PICCs) are frequently used to deliver outpatient courses of intravenous therapy. However, the rates and risks of complication for this device have not been well-studied. Our objective was to determine the incidence and risk factors of PICC-related complications with a 1-year prospective observational study. PATIENTS AND METHODS: All PICCs inserted in adult and pediatric patients at Memorial Sloan-Kettering Cancer Center (MSKCC) were followed prospectively. The device insertion team, inpatient nurses, and various home-care companies and outside institutions collected longitudinal data. RESULTS: Three hundred fifty-one PICCs were inserted during the study period and followed for a total of 10,562 catheter-days (median placement, 15 days; range, 1 to 487 days). Two hundred five PICCs (58%) were managed by home-care companies and outside institutions, and 146 PICCs (42%) were managed exclusively at MSKCC. For these 205 PICCs, 131 nurses from 74 home-care compa...
Estimating accounting and finance models with Microsoft Excel

Purpose – The purpose of this paper is to propose a way to introduce regression analysis into courses with minimal start‐up time. Doing so makes it less likely that introducing both the software and the estimation technique will create discontinuity in the flow of the material being covered.Design/methodology/approach – This paper discusses an Excel workbook that reduces the amount of time students must use to become adept at estimating model parameters.Findings – The workbook provides a set of macros that guides students through the implementation of ordinary least squares (OLS) estimation and provides them with information that is not part of standard Excel output. It also conducts high‐low analysis.Originality/value – Using this program can reduce the difficulties encountered in having students conduct the valuable exercise of model estimation.
Experimental demonstration of a quantum circuit using linear optics gates

One of the main advantages of an optical approach to quantum computing is the fact that optical fibers can be used to connect the logic and memory devices to form useful circuits, in analogy with the wires of a conventional computer. Here we describe an experimental demonstration of a simple quantum circuit of that kind in which two probabilistic exclusive-OR (XOR) logic gates were combined to calculate the parity of three input qubits.
Evaluating rates and yields of second-order, photoinitiated reactions under conditions of Gaussian-profile excitation

Under conditions of Gaussian radial profile excitation, a mixed-order kinetic model is used to interpret the rates and yields of photoinitiated reactions. This model is used to determine the triplet-triplet annihilation rate constant for benzophenone in acetonitrile and anthracene at room temperature. 34 refs., 9 figs.
The therapy alliance: a moderator in therapy outcome for families dealing with child abuse and neglect

The role of the therapy alliance in therapy outcome for families dealing with child abuse and neglect was examined using the family as the unit of analysis. The alliance was tested as a moderator in relationship to posttreatment levels of symptom distress and physical violence. Results show that the bonds, goals, and tasks subscale scores are significantly related to posttreatment levels of symptom distress and that the goals subscale score is significantly related to posttreatment level of violence. There is an interaction between bonds and level of violence at intake, suggesting that the greater the level of violence at intake, the more important the bonds domain.
Neural stimulation with a carbon nanotube microelectrode array.

We present a novel prototype neural interface using vertically aligned multiwalled carbon nanotube (CNT) pillars as microelectrodes. Functionalized hydrophilic CNT microelectrodes offer a high charge injection limit (1−1.6 mC/cm2) without faradic reactions. The first repeated in vitro stimulation of hippocampal neurons with CNT electrodes is demonstrated. These results suggest that CNTs are capable of providing far safer and more efficacious solutions for neural prostheses than previous metal electrode approaches.
Contributions of the National Ignition Facility to the development of inertial fusion energy

Abstract The US Department of Energy is proposing to construct the National Ignition Facility (NIF) to embark on a program to achieve ignition and modest gain in the laboratory early in the next century. The NIF will use a ⩾ 1.8 MJ, 0.35 μm laser with 192 independent beams, a 50-fold increase over the energy of the Nova laser. System performance analyses suggest yields as great as 20 MJ may be achievable. NIF will conduct more than 600 shots per year. The benefits of a micro-fusion capability in the laboratory include essential contributions to defence programs, resolution of important Inertial Fusion Energy (IFE) issues and unparalleled conditions of energy density for basic science and technology research. A start has been made to consider the role the NIF will fill in the development of IFE. While the achievement of ignition and gain speaks for itself in terms of its impact on developing IFE, it is believed there are areas of IFE development, such as fusion power technology, IFE target design and fabrication and understanding chamber dynamics, that would significantly benefit from NIF experiments. In the area of IFE target physics, ion targets will be designed using the NIF laser and the feasibility of high-gain targets will be confirmed. Target chamber dynamics experiments will benefit from X-ray and debris energies that mimic the spatial distribution of neutron heating, activation and tritium breeding in relevant materials. IFE target systems will benefit from evaluating low-cost target fabrication techniques by testing such targets on NIF. Additionally, it is believed that it is feasible to inject up to four targets and engage them with the NIF laser by triggering the beams in groups of ca. 50 separated in time by ca. 0.1 s. Sub-ignition neutron yields would allow an indication of symmetry achieved in such proof-of-principle rep-rate experiments. NIF will be a unique source of data to benchmark predictive capabilities to support affordable IFE technology selections. The total of NIF-IFE experiments may involve several thousands of shots. NIF may support design “certification” for the follow-on facility to NIF, dedicated to IFE, called the Engineering Test Facility.
Patient specific optimization-based treatment planning for catheter-based ultrasound hyperthermia and thermal ablation

A 3D optimization-based thermal treatment planning platform has been developed for the application of catheter-based ultrasound hyperthermia in conjunction with high dose rate (HDR) brachytherapy for treating advanced pelvic tumors. Optimal selection of applied power levels to each independently controlled transducer segment can be used to conform and maximize therapeutic heating and thermal dose coverage to the target region, providing significant advantages over current hyperthermia technology and improving treatment response. Critical anatomic structures, clinical target outlines, and implant/applicator geometries were acquired from sequential multi-slice 2D images obtained from HDR treatment planning and used to reconstruct patient specific 3D biothermal models. A constrained optimization algorithm was devised and integrated within a finite element thermal solver to determine a priori the optimal applied power levels and the resulting 3D temperature distributions such that therapeutic heating is maximized within the target, while placing constraints on maximum tissue temperature and thermal exposure of surrounding non-targeted tissue. This optimizationbased treatment planning and modeling system was applied on representative cases of clinical implants for HDR treatment of cervix and prostate to evaluate the utility of this planning approach. The planning provided significant improvement in achievable temperature distributions for all cases, with substantial increase in T90 and thermal dose (CEM43T90) coverage to the hyperthermia target volume while decreasing maximum treatment temperature and reducing thermal dose exposure to surrounding non-targeted tissues and thermally sensitive rectum and bladder. This optimization based treatment planning platform with catheter-based ultrasound applicators is a useful tool that has potential to significantly improve the delivery of hyperthermia in conjunction with HDR brachytherapy. The planning platform has been extended to model thermal ablation, including the addition of temperature dependent attenuation, perfusion, and tissue damage. Pilot point control at the target boundaries was implemented to control power delivery to each transducer section, simulating an approach feasible for MR guided procedures. The computer model of thermal ablation was evaluated on representative patient anatomies to demonstrate the feasibility of using catheter-based ultrasound thermal ablation for treatment of benign prostate hyperplasia (BPH) and prostate cancer, and to assist in designing applicators and treatment delivery strategies.
Substructure and configuration of ribosomes isolated from mammalian cells

Abstract Neoplastic mouse plasma-cells (RPC-20 plasma-cell tumor) contain metabolically active ribosomes, some of which are free in the cytoplasm whereas others are bound to cytoplasmic membranes. Rabbit reticulocytes synthesizing hemoglobin appear to contain only free ribosomes. When tumor cells were disrupted by homogenization and rabbit reticulocytes were lysed in appropriate media and nuclei and debris were removed by centrifugation, the resulting supernatant fluids were used to make preparations suitable for examination with the electron microscope. A spectrum of free ribosomes, ranging in size from monomers to polymers containing 25 to 30 units, could be obtained by sampling from a continuous sucrose density gradient after ultra centrifugation. Membrane-bound ribosomes were obtained either directly from the supernatant fluid or from the bottom of the gradient. Films of the ribosomes prepared on carbon-coated, Formvar-covered grids were negatively and positively stained. The monomeric ribosomes consisted of a large, morphologically stable subunit and a small subunit whose variable morphology suggested structural instability or functional significance. When small polyribosomes of four to nine members formed circles or rosettes, the small subunit was always oriented toward the center, while large polyribosomes, whose individual members were arranged along an axis passing through the small subunit, were disposed in shapes suggestive of flattened helices. A model for the metabolically active, free polyribosome is proposed. It consists of ribosomes arranged in a helix, with the small subunits forming a central core and the large subunits arranged around the periphery. Membrane-bound ribosomes were attached to the membranes by the large subunit.
EFFECT OF PHENOXYBENZAMINE ON PHAGOCYTIC ACTIVITY AND SHOCK MORTALITY IN THE RAT.

SummaryPhenoxybenzamine (PBZ—0.5 mg/kg) decreased, and blockade of the reticulosndothelial system with colloidal carbon (320 mg/kg) temporarily increased the mortality of rats to subsequent tumbling shock. The usual protective effect of PBZ was lost if the drug was given after carbon blockade; in contrast, PBZ maintained its protective effect if given before blockade although “acute” traumatic deaths incident to drumming increased. PBZ pretreatment had no effect on pre-shock or post-shock carbon clearance activity either in the intact rat or in the in situ perfused liver. The results indicate that in the rat carbon clearance activity is not well correlated with the protective action of PBZ in traumatic shock.We express our thanks to Smith, Kline and French Laboratories, Philadelphia, Pa., for phenoxybenzaminc hydrochloride (Lot 127-DI-(1)) used in this study.
High temperature silver-indium joints manufactured at low temperature

Abstract A fluxless bonding process using indium-silver multilayer composite to produce high temperature joints at relatively low temperature has been developed. The process temperature is 220°C. Joints, which are almost void-free, with melting temperatures of 210°C are first made. After further annealing at 130°C, the re-melting temperature increases to above 750°C. The technique, thus, provides a quantum jump to the post-processing temperature of component fabrication. The joints are examined using a scanning acoustic microscope to confirm the bonding quality. The joint cross-sections are studied using scanning electron microscopy and energy dispersive X-rays to find the microstructure and composition. Upon deposition, In reacts with Ag to form In–AgIn2 composite. The intermetallic compound AgIn2 prevents the In layer from oxidation in atmosphere. Thus no flux is needed. Besides the fluxless feature, the low process temperature would significantly reduce the stresses developed due to thermal expansion mismatch comparing to the otherwise high temperature process with temperature exceeding the melting temperature. The multilayer bonding method also facilitates precise control of the alloy composition and the joint thickness. The new technique should find applications in the emergent high temperature electronic devices.
Archeological and environmental lessons for the Anthropocene from the Classic Maya collapse

Abstract The original formulation of the “Anthropocene” emphasized the global environmental change resulting from expanding human populations and fossil fuel burning since the industrial revolution of the late 18th century. Politically, the message is that scientists and engineers should work toward an internationally accepted sustainable future. This assumes, and is dependent upon, maintaining the integrity of our increasingly interconnected social, economic, and political systems worldwide. Anthropogenic environmental change and degradation (e.g., global warming, sea-level rise, erosion) within the context of the Anthropocene has the potential to displace populations, undermine food security and human health, stimulate conflict, and destabilize social, economic and political systems. Ultimately, we do not know if our political systems could withstand these forces or whether degradation would lead to increased war and further environmental degradation. We can, however, study the complex processes of political collapse retrospectively in the archeological and historical records. In this paper, we examine one such predecessor in world history, the widespread collapse of Classic Maya polities within the context of anthropogenic and climate-driven environmental change between AD 600 and 1000. We conclude that the staggered collapse of inter-connected and rigidly organized political centers ultimately resulted from multiple drivers including anthropogenic and climate-driven environmental change. Any way one looks at Maya history suggests a precursor toward the Anthropocene: greatly changed forests and soils, water management and food production, population increase and aggregation, and even alteration of local hydrology and climate caused by deforestation and wetland manipulation.
Blood Flow Determination From Fluoroscopic Image Sequences

In this paper a method to quantitate blood flow from contrast injections into a vessel was evaluated using a straight tube, constant flow phantom. Grey scale values integrated over multiple regions-of-interest (ROI), placed contiguously along a "vessel" segment, were used to generate multiple time-density curves. Temporal shifts in the time-density curves for each ROI were determined using a cross-correlation technique. Regional volume estimates were made using a curve fitting approach. Linear regression of the regional volume and temporal shift estimates was used to estimate flow within the vessel segment. Velocity estimates were made in a similar way. Currently, velocity estimations are significantly better than flow estimations. Errors in the diameter estimates remain as the main cause of flow inaccuracies.
The treatment of deep venous thrombosis, including the newer agents.

arritt and Jordan performed the first and only randomized trial of reatment of venous thromboembolism [VTE—deep venous thrombosis DVT) and pulmonary embolism (PE)] with unfractionated heparin odium (UFH) and an oral vitamin K antagonist at Bristol Royal nfirmary in 1957. This study reported a 26% mortality rate (5 of 19 in he control arm) for untreated patients with VTE. Today, the mortality ssociated with untreated PE is reported as approximately 30%, a figure hat has not changed since the publication of this landmark study. The study by Barritt and Jordan was quickly incorporated into standard ractice for treatment of VTE with anticoagulation. Further, the improved utcomes for patients with PE were soon extrapolated to patients for reatment of uncomplicated DVT alone.
The dawn of nicotinamide coenzyme research

the discovery of pyruvic acid carboxylase in yeast may have led to this interpretation. As a part of a long series of investigations on alcoholic fermentation, Kostytschew 4 in 1927 published a paper entitled 'The non-existence of cell-free fermentation', in which he took issue with the term coferment: 'Should one succeed in dropping the concept of coferments, a considerable cleansing of the field of research on ferments would be achieved'. That this was not an isolated view is exemplified by a similar comment of Kluyver 5 in 1928: 'In the meantime, we would prefer to delete the concept of a coenzyme altogether from the literature'. This attitude, however, was not shared by others. In the early twenties, a long series of investigations on the coenzyme (then termed cozymase) was started by yon Euler, who proved its existence beyond doubt and, among other properties, described its relationship to AMP. In 1929, Harden and von Euler shared the Nobel Prize in Chemistry for 'their investigations on the fermentation of sugar and on fermentative enzymes'. ~[he key to the successful purification of NAD ÷, particularly by Myrbaeck 6, was a simple test system consisting of dried and partially autolysed yeast, from which the coenzyme could be selectively removed by repeated washing with water. In analogy to Harden's experiment, this yeast preparation, termed apozymase, was stimulated to ferment glucose by the addition of the coenzyme, either crude or after various steps of purification. Highly purified NAD ÷ was obtained in
Patterns and Predictors of Involvement Among Fathers of Children Born to Adolescent Mothers

Father involvement may be an important support for children born to adolescent mothers. This study examines patterns and predictors of father involvement, as reported by adolescent mothers, from their child's infancy through toddlerhood. Data were collected from urban, primarily African American, adolescent mothers (N = 138) in four interviews, over a 24-month period. The percentage of fathers categorized as “highly involved” decreased significantly from baseline to 12-month follow-up and was stable through 24 months. The romantic status of the mother–father relationship was the strongest predictor of whether father involvement was consistently high, consistently low, or decreased over time.
Photoperiodic and light spectral conditions which inhibit circulating concentrations of thyroxine in the male hamster.

Abstract Adult male Syrian hamsters were exposed daily for 12 weeks to 11 h/day of cool white fluorescent light (350 ± 50 μ W/cm 2 ) followed by an additional 3 h of near ultraviolet (339−317 nm), blue (435–500 nm), green (515–550 nm), yellow (558–636 nm) or red (653–668 nm) light at an irradiance of 0.2 μW/cm 2 or to total darkness. Animals exposed to the wavelengths between 558–668 nm (yellow or red half peak bandwidths) or those receiving a total of 13 h of darkness/day had suppressed circulating levels of thyroxine (T 4 ), a depressed free T 4 index (FT 4 I) and a higher T 3 /T 4 ratio compared to animals receiving a total of 14 h of white light (350 ± 50 μ W/cm 2 ). These results suggest that specific wavelengths of light can affect the neuroendocrine-thyroid axis.
Butterfly visual characteristics and ontogeny of responses to butterflies by a specialized tropical bird

The responses of two adult and three hand-reared, naive young rufous-tailed jacamars (Galbula ruficauda) to local butterflies were studied in feeding experiments. Four behavioural characteristics distinguish jacamars from other less specialized avian predators: (1) Exposed to butterflies for the first time, naive young jacamars would attack butterflies without showing signs of inhibition. Unacceptable butterflies, once captured, were taste-rejected quickly, and most survived the sampling. The few presumably unacceptable butterflies consumed by the birds were not observed to cause vomiting. (2) After gaining some familiarity with butterflies, young birds, like the adults, developed a reluctance to attack. They visually rejected certain classes of butterflies, often failing to attack them during an entire four-hour feeding trial. However, occasional attacks were made on butterflies in these ‘rejected’ classes. When this did occur, the insects proved to be actually easier to catch than those that were more often attacked. Once captured, however, the majority of these butterflies were taste-rejected. (3) For a given butterfly species, most individuals were either consumed or rejected. Thus, each species could be clearly classified as either acceptable or unacceptable to the jacamars. This consistency in jacamar responses resulted in a bimodal acceptability distribution of sympatric butterflies. (4) Young jacamars were capable of rapid associative learning and their responses were closely associated with butterfly visual characteristics in which colour pattern, flight behaviour, and morphology were also closely correlated. Thus, a single butterfly morphological parameter termed body shape (body length/thoracic diameter ratio) can adequately predict the feeding responses of jacamars. Visually detectable traits associated with butterflies possessing chemical defences may represent a balance between the need to signal unambiguously to specialized and/or experienced predators and the need to escape attacks by generalized and/or opportunistic predators. Since the proportion of specialized predators is higher in the tropical rainforest than in other habitat types, we expect greater divergence of morphological and behavioural characteristics between palatable and unpalatable butterflies in rainforest habitats.
Stokes parameters in undergraduate laboratory exercises

Polarization is a concept most students readily understand in terms of the preferential direction of electric field vectors. The visualization of the electric field component of an electromagnetic wave facilitates the understanding of a large body of knowledge concerning propagation and measurement of completely and partially polarized light. Little known to undergraduate students, however, is the Stokes parameters and students typically receive a cursory treatment regarding their usefulness in describing and measuring polarized light in a laboratory or astronomical setting. We present laboratory exercises where students use Stokes parameters when measuring and describing the polarization of electromagnetic radiation and in the statistical analysis of polarized light.
PREFERRED SEQUENCES WITHIN A DEFINED CLEAVAGE WINDOW SPECIFY DNA 3' END-DIRECTED CLEAVAGES BY RETROVIRAL RNASES H

The RNase H activity of reverse transcriptase carries out three types of cleavage termed internal, RNA 5′ end-directed, and DNA 3′ end-directed. Given the strong association between the polymerase domain of reverse transcriptase and a DNA 3′ primer terminus, we asked whether the distance from the primer terminus is paramount for positioning DNA 3′ end-directed cleavages or whether preferred sequences and/or a cleavage window are important as they are for RNA 5′ end-directed cleavages. Using the reverse transcriptases of human immunodeficiency virus, type 1 (HIV-1) and Moloney murine leukemia virus (M-MuLV), we determined the effects of sequence, distance, and substrate end structure on DNA 3′ end-directed cleavages. Utilizing sequence-matched substrates, our analyses showed that DNA 3′ end-directed cleavages share the same sequence preferences as RNA 5′ end-directed cleavages, but the sites must fall in a narrow window between the 15th and 20th nucleotides from the recessed end for HIV-1 reverse transcriptase and between the 17th and 20th nucleotides for M-MuLV. Substrates with an RNA 5′ end recessed by 1 (HIV-1) or 2–3 (M-MuLV) bases on a longer DNA could accommodate both types of end-directed cleavage, but further recession of the RNA 5′ end excluded DNA 3′ end-directed cleavages. For HIV-1 RNase H, the inclusion of the cognate dNTP enhanced DNA 3′ end-directed cleavages at the 17th and 18th nucleotides. These data demonstrate that all three modes of retroviral RNase H cleavage share sequence determinants that may be useful in designing assays to identify inhibitors of retroviral RNases H.
The octopus and the child—Another perspective on American culture: A commentary on Stearns

Stearns argues that, in the twentieth century, American parents increasingly treated their children as frail and vulnerable. But the parental protectiveness that he describes is only one part of the story. Some American parents did hover over their children; others ignored, neglected, or abused them. Some did shore up their suspect self-esteem; others trusted in their strength and sturdiness and even demanded a new toughness and competitiveness. American culture is more complicated and contested than Stearns allows.
Potential changes in world oil prices on the U.S.: A general equilibrium perspective

Abstract This study, using a general equilibrium approach, attempts to measure the impact of higher world prices on the various sectors of the U.S. economy. The model is composed of 12 producing sectors, 13 consuming sectors, 6 household categories classified by income, a foreign sector and a government. The result of this study suggest that generally higher petroleum prices will be followed by lower output, higher consumption of goods and services, and a loss in consumer welfare.
Effect of Automated Egg Injections on Livability and Growth of Turkey Poults

Abstract A study was conducted to evaluate the influence of automated injections on poult viability after hatching. The study was completed as a replica of previous large-scale commercial investigations, wherein eggs were injected at 25 days of incubation with D-biotin in saline solution and saline solution alone in order to compare hatchability with that of uninjected eggs. Each of the three treatments utilized 240 embryonated eggs. After hatching, 100 female poults from each treatment were place in cartons and shipped 350 miles to the location of the viability study. Researchers placed poults in each treatment in separate floor pens and gave them free access to a 28% protein diet and water. At 2 wk of age, poults in each treatment were assigned of four replicate pens, with twenty-four poults of equal average body weight per pen. Poult livability and growth did not differ at 9 to 2 wk of age and 2 to 9 wk of age between injected and uninjected eggs.
229 OOCYTE RECOVERY, IN VITRO FERTILIZATION AND EMBRYO TRANSFER IN THE SERVAL (LEPTAILURUS SERVAL)

Servals are medium size (9 to 18 kg) spotted cats found in sub-Saharan Africa that are protected by CITES under Appendix II regulations. There are at least six sub-species, one of which is listed as Endangered by the U.S. Endangered Species Act. In vitro-derived embryos have been produced in at least one-half of the 36 species of nondomestic cats, and kittens have been born after embryo transfer in six species. In the present study we evaluated (1) ovarian response of servals to repeated exogenous gonadotropin stimulation, and (2) in vitro and in vivo developmental ability of in vitro-derived embryos. One two-year-old and one five-year-old female were treated six and three times, respectively, over a 3.5-year period, with a total of 20 or 25 IU of porcine FSH (i.m.; Sioux Biochem, Sioux City, IA, USA) administered daily over four days during interestrus. On Day 5, 15 IU of porcine LH (i.m.; Sioux Biochem) was given, and laparoscopic oocyte retrieval was performed 24 h later. A total of 234 preovulatory oocytes were recovered: 182 (mean = 30.3) from the two-year-old and 52 (mean = 17.3) from the five-year-old female. A total of 91 and 91 oocytes were recovered at retrievals 1 through 3 and 4 through 6, respectively, from the two-year-old donor. Eighty oocytes from the two-year-old donor were inseminated with cooled (24 h, 4°C) semen. Frozen semen from the same male was used to inseminate 102 oocytes from the two-year-old female and 52 oocytes from the five-year-old female. Overall, 136 embryos (58% cleavage frequency) were produced: 119 (65% cleavage frequency) from the two-year-old and 17 (33% cleavage frequency) from the five-year-old female. Cleavage frequency of oocytes from the two-year-old female inseminated with cooled or frozen semen was similar, 68% (54/80) and 64% (65/102), respectively. Embryos were cultured for 5 or 6 days before controlled rate cryopreservation or uterine transfer (Gomez et al. 2003 Theriogenology 60, 239–251). On Day 5, 66 early to mid-stage morulae were cryopreserved at a slow controlled rate. Sixty Day 5 and 18 Day 6 embryos were auto-transferred to a recipient (8 to 26/transfer) in a total of six surgical procedures, of which five were with fresh embryos (n = 70) and one was with cryopreserved embryos (n = 8). The sixth embryo transfer procedure (26 fresh embryos) resulted in the unassisted birth of a live male kitten on Day 77 of gestation. We have shown that in vitro-derived embryos can be generated in the serval and that oocyte retrieval rates and cleavage frequencies are comparable to those reported for other species of mid-sized nondomestic cats. The nominal incidence of pregnancy and frequency of embryo survival may be improved by transferring early cleavage staged embryos into the oviduct, as demonstrated in the African wildcat (Felis silvestris lybica; Gomez et al. 2004 Cloning and Stem Cells 6, 247–258). This work was partially funded by the Dan Heard Conservation Challenge Grant.
Lipoprotein Staining Following Polyacrylamide Disc Electrophoresis of Chick Serum

Abstract DISC GEL electrophoresis has provided a technique for rapidly resolving whole serum into more than twenty protein fractions (Davis and Ornstein, 1959). Our investigations of the serum protein changes of the chick during the first days after hatching (Libby et al., 1966) require identification and routine determination of these proteins. The major problems arising in the evaluation of the lipoprotein fractions have been caused by the inadequacy of analytical ultracentrifugation and moving boundary electrophoretic techniques (Narayan et al., 1965). Attempts to resolve and identify these fractions by varying gel pore size and staining techniques have usually given unsatisfactory results and are complicated to perform (Raymond et al., 1966). Furthermore, prestaining the lipid fractions may alter the charge on the protein and consequently, its migration in the electrical field. This alteration makes it difficult to compare gel fractions. The present work describes lipoprotein staining techniques performed on polyacrylamide disc gels after . . .
Serotonergic modulation of male-like pseudocopulatory behavior in the parthenogenetic whiptail lizard, Cnemidophorus uniparens.

Hormone–neurotransmitter interactions form an important link through which hormones influence a variety of behavioral processes. Typically, sexual behavior is dimorphic with males mounting receptive females. In the all-female lizard species Cnemidophorus uniparens, individuals display both male-like pseudocopulation and female-like receptivity. These respective behavioral states are correlated with high circulating concentrations of progesterone following ovulation and of estrogen preceding it. In sexual species, serotonin is involved in male-typical mounting, and, as reported here, in male-like pseudosexual behavior in this unisexual species. In the first study, C. uniparens were ovariectomized and treated systemically with exogenous androgen, a hormonal regimen that results in individuals displaying only male-like pseudosexual behavior. An increase in serotonin levels in the preoptic area coupled with the suppression of male-like pseudocopulation was observed in androgen-treated lizards injected with 5-hydroxytryptophan (the precursor of serotonin) and clorgyline (a monoamine oxidase inhibitor) compared to vehicle-treated controls. Our second experiment involved ovariectomizing lizards and either injecting them with estradiol or implanting them with either an empty (Blank) or a progesterone- or testosterone-containing Silastic capsule. Treatment with para-chlorophenylalanine (an inhibitor of tryptophan hydroxylase) facilitated male-like pseudosexual behavior depending on the circulating hormonal milieu and decreased serotonin levels in the preoptic area. Our data suggest that serotonin is inhibitory to male-like pseudosexual behavior in C. uniparens but more importantly that the hormonal environment modulates the serotonin system at the level of the preoptic area, with the serotonergic system then establishing behavioral thresholds that allow for this behavior to be “gated”.
THE PLECKSTRIN HOMOLOGY DOMAINS OF DYNAMIN ISOFORMS REQUIRE OLIGOMERIZATION FOR HIGH AFFINITY PHOSPHOINOSITIDE BINDING

Abstract The dynamins are 100-kDa GTPases involved in the scission event required for formation of endocytotic vesicles. The two main described mammalian dynamins (dynamin−1 and dynamin−2) both contain a pleckstrin homology (PH) domain, which has been implicated in dynamin binding to (and activation by) acidic phospholipids, most notably phosphoinositides. We demonstrate that the PH domains of both dynamin isoforms require oligomerization for high affinity phosphoinositide binding. Strong phosphoinositide binding was detected only when the PH domains were dimerized by fusion to glutathioneS-transferase, or via a single engineered intermolecular disulfide bond. Phosphoinositide binding specificities agreed reasonably with reported effects of different phospholipids on dynamin GTPase activity. Although they differ in their ability to inhibit rapid endocytosis in adrenal chromaffin cells, the dynamin−1 and dynamin−2 PH domains showed identical phosphoinositide binding specificities. Since oligomerization is required for binding of the dynamin PH domain to phosphoinositides, it follows that PH domain-mediated phosphoinositide binding will favor oligomerization of intact dynamin (which has an inherent tendency to self-associate). We propose that the dynamin PH domain thus mediates the observed cooperative binding of dynamin to membranes containing acidic phospholipids and promotes the self-assembly that is critical for both stimulation of its GTPase activity and its ability to achieve membrane scission.