bluuebunny/crossref_metadata_2025 huggingface dataset:
The Heiress-at-Law: English Real Property Law from a New Point of View
Authors: Spring Eileen
Published: April 2006

By the common law rules of inheritance women in English landed society fell into two classes. Some were altogether excluded from inheriting; others were entitled to succeed to the family estate. The woman thus entitled, the heiress-at-law, is clearly a figure due historical attention. Yet she has never been singled out for long-term consideration. Where she has been the main subject, discussion has always been chronologically limited, and her history has not been carried any distance through the course of legal changes that are relevant to it. Usually she has been discussed as but part of the family, and attention has been focussed largely on eldest sons and their relations with younger children, with younger sons or with daughters not heiresses, as the case may be. To focus on the heiress and to follow her history over the long run, from the thirteenth century to the eighteenth, is the purpose of this article.
Langdell's Auto-da-fé
Authors: Schlegel John Henry
Published: April 2006

As one who has suggested in print that Christopher Columbus Langdell was a loony, I am singularly pleased that Bruce Kimball has so carefully demonstrated that Kit was a regular guy just trying to teach his classes and learn some law. But this observation seems to me to be not particularly relevant to the debate about Langdell that I have mostly watched, but occasionally commented on. I shall try to recreate that debate as best I can, to show where it stands, and so, to identify where an understanding of Langdell's teaching places us.
The Voice of Willard Hurst
Authors: Konefsky Alfred S.
Published: April 2006

Though I corresponded with Willard Hurst over the last twenty-five years, I met him only once. Hurst did not often attend events or meetings outside of Madison, but in 1971 he appeared at a legal history conference at the Harvard Law School to herald the renaissance in the field of American legal history, a renewal in many ways directly traceable to Hurst's own work and influence. I had just graduated from law school and was beginning my apprenticeship as a legal historian. With great trepidation I walked up to him to introduce myself at a reception on the first day of the conference. I was surprised when he seemed to recognize my name (I think a list of conference participants may have been circulated in advance), but even more astonished when he said, “Let's go find a quiet corner, I want to talk to you about your father.” My father, Samuel J. Konefsky, had died less than a year before, and Hurst's brief conversation with me was the first of the many kindnesses of his that I experienced.
Hurst Recaptured
Authors: Gordon Robert W.
Published: April 2006

Anyone who lived and worked within range of Willard Hurst's benign, if also rather insistent, influence is necessarily somewhat disabled from detached assessment of his legacy. We owe him too much. Not just for the continuous rapid fire of comment, criticism, recommendation, and encouragement that rattled off the famous ancient typewriter; but also for his intellectual and moral example. He set himself long-range projects and finished them; he surveyed large themes and explored them to the bottom. He used his authority to try to get us both to read more broadly and get down into the details. We responded because we were touched that he thought our work might matter, and because he did not spare himself. Even when rebelling against that authority (as I for one often did), we wanted his attention and judgment even when we could not hope for his approval, and he gave them generously.
Rights Talk in Canada in the Late Nineteenth Century: “The Good Sense and Right Feeling of the People”
Authors: Risk Richard , Vipond Robert C.
Published: April 2006

I am a friend to the preservation of the rights of property…but I believe in the subordination of those rights to the public good…. I deny that the people of my Province are insensible to or careless about the true principles of legislation. I believe they are thoroughly alive to them, and I am content that my rights of property, humble though they are, and those of my children, shall belong to the Legislature of my country to be disposed of subject to the good sense and right feeling of the people of that Province.

Edward Blake made this declaration about property in 1882. Presumably his beliefs were widely shared by Canadian lawyers, for he was the leader of the Liberal party, the Treasurer of the Law Society of Upper Canada (Ontario), and one of the leading counsel. We seek to explore his beliefs and to reconstruct the understandings of rights in late nineteenth-century Canada, and especially the understandings of common-law lawyers.
Structurally Unique Biflavonoids from Selaginella chrysocaulos and Selaginella bryopteris
Authors: Swamy Ramalla Chidananda , Kunert Olaf , Schühly Wolfgang , Bucar Franz , Ferreira Daneel , Rani Vanapatla Swarupa , Kumar Bobbala Ravi , Appa Rao Achanta Venkata Narasimha
Published: April 2006

Chemical investigation of Selaginella chrysocaulos from Northeast India yielded three new (i.e., 1–3) and two known biflavonoids. From Selaginella bryopteris, collected in the southern part of India, one new (11) and eleven known biflavonoids of the amentoflavone‐ and hinokiflavone‐type were isolated and identified. The structures of the compounds were elucidated by 1D‐ and 2D‐NMR spectroscopy, and by mass spectrometry. The absolute configurations of chiral biflavonoids with flavanone subunits (from S. bryopteris) were determined with the aid of circular‐dichroism (CD) spectroscopy. Several very rare or even unprecedented substructures in biflavonoids were found.
Plutonium Speciation Affected by Environmental Bacteria
Authors: Neu Mary P. , Icopini Gary A. , Boukhalfa Hakim
Published: April 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Efficacy of etifoxine compared to lorazepam monotherapy in the treatment of patients with adjustment disorders with anxiety: a double‐blind controlled study in general practice
Authors: Nguyen N. , Fakra E. , Pradel V. , Jouve E. , Alquier C. , Le Guern M‐E. , Micallef J. , Blin O.
Published: April 2006

Adjustment Disorders With Anxiety (ADWA) account for almost 10% of psychologically motivated consultations in primary care. The aim of this double‐blind randomised parallel group study was to compare (non‐inferiority test) the efficacies of etifoxine, a non‐benzodiazepine anxiolytic drug, and lorazepam, a benzodiazepine, for ADWA outpatients followed by general practitioners. 191 outpatients (mean age: 43, female: 66%) were assigned to receive etifoxine (50 mg tid) or lorazepam (0.5‐0.5‐1 mg /day) for 28 days. Efficacy was evaluated on days 7 and 28 of the treatment. The main efficacy assessment criterion was the Hamilton Rating Scale for Anxiety score (HAM‐A) on Day 28 adjusted to Day 0. The anxiolytic effect of etifoxine was found not inferior to that of lorazepam (HAM‐A score decrease: 54.6% vs 52.3%, respectively, p = 0.0006). The two drugs were equivalent on Day 28. However, more etifoxine recipients responded to the treatment (HAM‐A score decreased by ≥50%, p = 0.03). Clinical improvement (based on Clinical Global Impression scale CGI, Social Adjustment Scale Self‐Report SAS‐SR, and Sheehan scores) was observed in both treatment arms, but more etifoxine patients improved markedly (p = 0.03) and had a marked therapeutic effect without side effects as assessed by CGI, p = 0.04. Moreover, 1 week after stopping treatment, fewer patients taking etifoxine experienced a rebound of anxiety, compared to lorazepam (1 and 8, respectively, p = 0.034). Copyright © 2006 John Wiley & Sons, Ltd.
The effect of harvest date on the yield and mineral content of Phalaris arundinacea L. (reed canary grass) genotypes screened for their potential as energy crops in southern England
Authors: Christian Dudley G , Yates Nicola E , Riche Andrew B
Published: April 2006

The effect of harvest date on dry matter production per hectare and moisture content of 13 genotypes of Phalaris arundinacea (reed canary grass) was studied between 1995 and 1998 and N, P and K concentration in biomass was measured in 1998. There were two winter harvests, the first at crop senescence and the second after a subsequent delay of several weeks which varied each year. Average dry matter production was higher at the first (conventional) harvest than at the delayed harvest except in 1996. Each year there were differences in yield between genotypes and some differences were significant. Delayed harvest reduced yield by an average of 24% in 1997 and 23% in 1998 when losses resulted from 48% loss of leaf and 16% of stem matter. Delayed harvest decreased moisture content by 50% in 1997 and 52% in 1998 but it was 49% higher in 1996. In 1998, delayed harvest did not reduce N concentration in all genotypes and the reduction of P was variable, but K concentration was reduced by an average of 54%. Results indicate the suitability of reed canary grass as a biofuel, and variability between genotypes offers potential for crop improvement through selection and breeding. Copyright © 2006 Society of Chemical Industry
Effects of tannic acid and quebracho tannins on in vitro ruminal fermentation of wheat and corn grain
Authors: Martínez Tomás F , McAllister Tim A , Wang Yuxi , Reuter Tim
Published: April 2006

Current understanding of the effect of moderate amounts of tannins on the utilization of protein contained in forages indicates beneficial effects when fed to ruminants. Nevertheless, there is little knowledge about the effects of tannins on the ruminal hydrolysis of starch‐rich concentrates. Modulation of the hydrolysis of starch may reduce the occurrence of metabolic disorders, such as acidosis, in ruminants consuming high‐grain diets. The effects of commercial tannic acid (hydrolysable tannins) and quebracho tannins (condensed tannins) (50 g kg−1 DM) on the in vitro fermentation of ground wheat and corn grains by mixed ruminal bacteria was examined. The architecture and chemical composition of wheat and corn endosperms might explain differences in fermentation rates, as well as in response to similar concentrations of tannins. Regardless of the source of tannin, microbial fermentation was inhibited in both grains, as demonstrated by a decline in gas production, DM disappearance, volatile fatty acids and ammonia production. However, these effects were more pronounced for wheat than corn grain, mostly during the initial stages of the incubation. Scanning electron microscopy revealed that both sources of tannins inhibited the microbial hydrolysis of the endosperm protein matrix. Tannins did not prevent bacterial attachment to starch granules, but starch hydrolysis was slowed indirectly as a result of a tannin‐mediated reduction in the degradation of the surrounding protein matrix. Tannins are likely to be more effective at modulating the rate of starch digestion in grains that possess a readily degradable protein matrix. Copyright © 2006 Society of Chemical Industry
Validity of the Canadian occupational performance measure
Authors: Chan Chetwyn C.H. , Lee Tatia M.C.
Published: April 2006

The Canadian Occupational Performance Measure (COPM) is used to assess clients' perceived performance of daily activities and their satisfaction with their performance. This study gathered evidence on the content‐related and criterion‐related validity of the instrument. Thirty‐nine adult clients with orthopaedic and stroke disabilities were assessed using the COPM as well as three criterion instruments. Nine individuals with expertise in clinical and measurement participated in a panel review to evaluate the test content of the COPM. Results suggested that the assessment content and processes reflected clients' occupational performance issues. Criterion‐related validity between the COPM and Functional Independence Measure was (r=−0.14 to 0.38), and with the Satisfaction with Performance Scaled Questionnaire was (r=−0.13 to 0.40). Evidence gathered indicated the importance of vigorously testing the appropriateness and meaningfulness of this clinical outcome measure. Further research should be directed at improving the standardization and clinical application of the COPM. Copyright © 1997 Whurr Publishers Ltd.
Long‐term Outcome following Laparoscopic Adrenalectomy for Large Solid Adrenal Cortex Tumors
Authors: Palazzo F. Fausto , Sebag Frederic , Sierra Mauricio , Ippolito Giuseppe , Souteyrand Philippe , Henry Jean‐François
Published: April 2006

Introduction

Laparoscopic adrenalectomy (LA) is the procedure of choice for small benign adrenal tumors. In the absence of local invasion or metastases, the preoperative diagnosis of an adrenocortical carcinoma (ACC) is difficult, often leaving size as the principal predictor of malignancy. Large tumors are resectable laparoscopically, but the long‐term outcome and therefore appropriateness of LA for cortical tumors > 6 cm is not known.

Methods

We reviewed the LA experience in our institution since its introduction in June 1994. Patients who underwent LA for solid cortical tumors ≥ 60 mm in diameter without preoperative or intraoperative evidence of malignancy were reviewed. Follow‐up data, including clinical examination, biochemical analysis, and repeat scans, were reviewed for evidence of local or systemic recurrent disease.

Results

Between 1994 and 2004 a total of 462 adrenalectomies were performed, 391 of which were done laparoscopically. Among them, 19 were solid cortical tumors ≥ 60 mm in diameter with no overt malignant preoperative or intraoperative characteristics: 9 nonsecreting tumors, 8 Cushing’s syndrome tumors (including 2 virilizing variants), 1 virilizing tumor, and 1 aldosteronoma. The mean age of the patients was 49.9 years (range 22–77 years), and the mean tumor size was 69.0 mm (range 60–80 mm). Histology confirmed a cortical adenoma in eight patients, malignant tumors in three, and indeterminate tumors in eight. The mean follow‐up was 34 months (range 4–108 months). Two patients died of systemic recurrent disease (liver metastases) at 10 and 19 months, respectively, following surgery; two other patients died 12 and 21 months, respectively following surgery owing to unrelated cardiovascular and cerebrovascular pathology. One patient underwent surgery for local recurrence 54 months after primary surgery; the remaining 14 patients are well with no clinical or radiologic evidence of recurrent disease.

Conclusions

Laparoscopic adrenalectomy for large solid cortical tumors without pre‐ or intraoperative evidence of malignancy is not contraindicated, and it is unlikely to have a deleterious effect on long‐term outcome. Each case should be considered individually. We provide an algorithm for the approach to adrenocortical tumors ≥ 6 cm.
Classical and Follicular Variant of Papillary Thyroid Carcinoma: A Comparative Study on Clinicopathologic Features and Long‐term Outcome
Authors: Lang Brian Hung‐Hin , Lo Chung‐Yau , Chan Wai‐Fan , Lam Alfred King‐Yin , Wan Koon‐Yat
Published: April 2006

Introduction

The follicular variant of papillary thyroid carcinoma (FVPTC) is the most common histologic subtype of papillary thyroid carcinoma (PTC). However, it is still controversial whether FVPTC should behave differently from classical PTC (CPTC). The present study aimed at evaluating any potential difference in clinicopathologic features and long‐term outcome of FVPTC as compared with CPTC.

Patients and Methods

Of 568 patients with PTC managed from 1973 to 2004, 308 were shown to have CPTC (54.2%) and 67 (11.8%) FVPTC after histologic review. The mean (± SD) follow‐up period was 11.3 (± 8.9) years. The two groups were compared in terms of clinicopathological features, treatment received, and outcome regarding recurrence and disease‐specific survival.

Results

There was no difference in age and gender ratio between the CPTC and FVPTC patients. Both groups had similar tumor characteristics in terms of tumor size, presence of multifocality, capsular invasion, lymphovascular permeation, and perineural infiltration. However, FVPTC patients had significantly fewer histologically confirmed cervical lymph node metastases (P = 0.027) and extrathyroidal involvement (P = 0.005). The proportion of bilateral resection, adjuvant radioactive iodine, and lymph node dissection did not differ significantly between the two groups. The FVPTC patients had a more favorable tumor risk by DeGroot classification (P = 0.003) and MACIS (Metastasis, Age, Completeness of excision, Invasiveness, and Size) score (P = 0.026). The 10‐ and 15‐year actuarial disease‐specific survivals did not differ significantly between FVPTC and CPTC patients (96.2% versus 90.7% and 96.2% versus 89.1%, respectively).

Conclusions

Although patients with FVPTC had more favorable clinicopathologic features and a better tumor risk group profile, their long‐term outcome was similar to that of CPTC patients.
Intraoperative Blood Salvage in Penetrating Abdominal Trauma: a Randomised, Controlled Trial
Authors: Bowley Douglas M. , Barker Philip , Boffard Kenneth D.
Published: April 2006

Background

Blood is a scarce and costly resource. Transfusion is often required after major trauma but blood may not be readily available, and concerns remain over the potential adverse consequences of allogeneic blood transfusion. Intraoperative blood salvage (IBS) is used extensively after blunt abdominal trauma, but when blood is contaminated by enteric contents its use has been considered contraindicated.

Methods

This was a randomised, controlled trial conducted with Ethical Review Board approval in an inner city trauma unit. Patients with penetrating torso injury requiring a laparotomy and who had exhibited hypotension either pre‐hospital or on arrival and in whom there was considered to be significant blood loss were randomly assigned to 2 groups. The control group was given allogeneic blood transfusion at the discretion of the attending medical staff. The cell save (CS) group underwent IBS with transfusion of both allogeneic and autologous blood. All patients received prophylactic antibiotics. The primary outcome was exposure to allogeneic blood up to the first 24 hours postinjury.

Results

Twenty‐three patients were entered into the control group and 21 into the CS group. The groups were equivalent in demographic details, injury patterns and injury severity. The mean volume of salvaged blood re‐infused in the CS group was 1,493 ml (range 0–2,690 ml). The mean number of units of allogeneic blood transfused in the first 24 hours in the control group was 11.17 compared to 6.47 in the CS group (P = 0.008). Enteric injury had been sustained in 17/23 (75%) of the control group and 18/21 (85%) of the CS group (P = NS). Survival in the control group was 8/23 (35%) compared to 7/21 (33.3%) in the CS arm (P = NS). Patients with documented postoperative sepsis were significantly more likely to die compared to those without sepsis (P = 0.04); however, those patients in the CS arm were no more likely to develop sepsis compared to those who received allogeneic blood alone.

Conclusion

In this randomised, controlled trial for patients with penetrating abdominal injuries, IBS led to a significant reduction in allogeneic blood usage with no discernable effect on rates of postoperative infection or mortality.
The influence of offshore windpower on demersal fish
Authors: Wilhelmsson Dan , Malm Torleif , Öhman Marcus C.
Published: April 2006

A significant expansion of offshore windpower is expected in northwestern Europe in the near future. Little is known about the impacts it may have on the marine environment. Here, we investigate the potential for wind turbines to function as artificial reefs and fish aggregation devices (FADs), i.e. whether they would locally increase fish densities or alter fish assemblages. Fish communities and habitat composition were investigated using visual transects at two windpower farms off the southeastern coast of Sweden, central Baltic Sea. Fish abundance was greater in the vicinity of the turbines than in surrounding areas, while species richness and Shannon–Wiener diversity (H′) were similar. On the monopiles of the turbines, fish community structure was different, and total fish abundance was greater, while species richness and diversity (H′) were lower than on the surrounding seabed. Blue mussels and barnacles covered most of the submerged parts of the turbines. On the seabed, more blue mussels and a lesser cover of red algae were recorded around the power plants than elsewhere. Results from this study suggest that offshore windfarms may function as combined artificial reefs and fish aggregation devices for small demersal fish.
Predicting the Nuclear Localization Signals of 107 Types of HPV L1 Proteins by Bioinformatic Analysis
Authors: Yang Jun , Wang Yi-Li , Si Lü-Sheng
Published: April 2006

In this study, 107 types of human papillomavirus (HPV) L1 protein sequences were obtained from available databases, and the nuclear localization signals (NLSs) of these HPV L1 proteins were analyzed and predicted by bioinformatic analysis. Out of the 107 types, the NLSs of 39 types were predicted by PredictNLS software (35 types of bipartite NLSs and 4 types of monopartite NLSs). The NLSs of the remaining HPV types were predicted according to the characteristics and the homology of the already predicted NLSs as well as the general rule of NLSs. According to the result, the NLSs of 107 types of HPV L1 proteins were classified into 15 categories. The different types of HPV L1 proteins in the same NLS category could share the similar or the same nucleocytoplasmic transport pathway. They might be used as the same target to prevent and treat different types of HPV infection. The results also showed that bioinformatic technology could be used to analyze and predict NLSs of proteins.
VICMpred: An SVM-Based Method for the Prediction of Functional Proteins of Gram-Negative Bacteria Using Amino Acid Patterns and Composition
Authors: Saha Sudipto , Raghava G.P.S.
Published: April 2006

In this study, an attempt has been made to predict the major functions of gram-negative bacterial proteins from their amino acid sequences. The dataset used for training and testing consists of 670 non-redundant gram-negative bacterial proteins (255 of cellular process, 60 of information molecules, 285 of metabolism, and 70 of virulence factors). First we developed an SVM-based method using amino acid and dipeptide composition and achieved the overall accuracy of 52.39% and 47.01%, respectively. We introduced a new concept for the classification of proteins based on tetrapeptides, in which we identified the unique tetrapeptides significantly found in a class of proteins. These tetrapeptides were used as the input feature for predicting the function of a protein and achieved the overall accuracy of 68.66%. We also developed a hybrid method in which the tetrapeptide information was used with amino acid composition and achieved the overall accuracy of 70.75%. A five-fold cross validation was used to evaluate the performance of these methods. The web server VICMpred has been developed for predicting the function of gram-negative bacterial proteins (http://www.imtech.res.in/raghava/vicmpred/).
Fragrep: An Efficient Search Tool for Fragmented Patterns in Genomic Sequences
Authors: Mosig Axel , Sameith Katrin , Stadler Peter
Published: April 2006

Many classes of non-coding RNAs (ncRNAs; including Y RNAs, vault RNAs, RNase P RNAs, and MRP RNAs, as well as a novel class recently discovered in Dictyostelium discoideum) can be characterized by a pattern of short but well-conserved sequence elements that are separated by poorly conserved regions of sometimes highly variable lengths. Local alignment algorithms such as BLAST are therefore ill-suited for the discovery of new homologs of such ncRNAs in genomic sequences. The Fragrep tool instead implements an efficient algorithm for detecting the pattern fragments that occur in a given order. For each pattern fragment, the mismatch tolerance and bounds on the length of the intervening sequences can be specified separately. Furthermore, matches can be ranked by a statistically well-motivated scoring scheme.
DAMAGES AT THE BORDERS OF LEGAL REASONING
Authors: Campbell David , Devenney James
Published: April 2006

IN Borders (U.K.) Ltd. and others v. Commissioner of Police of the Metropolis and another, the Court of Appeal has, yet again, succumbed to the “temptation to do justice” by further extending to claimants a disgorgement remedy on the claimed authority of A.G. v. Blake (Jonathan Cape Ltd. Third Party). We say “claimed authority” because, yet again, the extension of the disgorgement remedy is impossible to justify using legal argument respectful of precedent, for such argument is subordinated to the direct “pursuit of the justice of the outcome” (para. [28]).
Body, Word, and Photograph: Sylvia Plath's Cold War Collage and the Thalidomide Scandal
Authors: PEEL ROBIN
Published: April 2006

My room is looking more and more like a picture gallery … or a kind of photographic shrine.
Lenny Bruce and his Nuclear Shadow Marvin Lundy: Don DeLillo's Apocalyptists Extraordinaires
Authors: ROSEN ELIZABETH
Published: April 2006

In the parlance of the time he was known as a “sick comedian.” He was also called a junkie, a hipster, a satirist, a shaman, a free-speech martyr, “a disease of America,” “a nightclub Cassandra,” and a prophet. But Lenny Bruce, the caustic comedian who gained a following in the late 1950s and early 1960s, called himself something else: a deviate. “All my humor is based on destruction and despair,” he said. “If the whole world were tranquil, without disease and violence, I'd be standing on the breadline.”
A strain-based Lagrangian-history turbulence theory
Authors: Kraichnan Robert H. , Herring Jackson R.
Published: April 2006

The Lagrangian-history method in turbulence theory (Kraichnan 1977) is modified such that triple moments are expanded in functional powers of the Lagrangian covariance of the symmetric rate-of-strain field instead of the Lagrangian covariance of the velocity field. The simplest approximation which results corresponds to the abridged Lagrangian-history direct-interaction approximation. It is illustrated by application to the Lagrangian properties of a random velocity field whose Eulerian values are frozen in time. Then it is formulated for isotropic Navier-Stokes turbulence. The new approximation is expected to give reduced energy transfer in the dissipation range because the rate of strain along a fluid-element trajectory is statistically stationary in stationary homogeneous turbulence while the derivatives of the Lagrangian velocity with respect to initial position tend to grow and thereby have a longer correlation time. The correlation times of these two entities play corresponding roles in the new and old approximations for energy transfer, respectively.
Thermal transpiration in a circular capillary with a small temperature difference
Authors: Porodnov B. T. , Kulev A. N. , Tuchvetov F. T.
Published: April 2006

The results of an experimental investigation of the thermal transpiration effect (the thermomolecular pressure difference or t.p.d. effect) in a single glass capillary with a length-to-radius ratio of 250 are presented. The temperatures of the gas in the ‘cold’ and ‘hot’ chambers were 273·2°K and 293°K, respectively. A modified relative method has been used. To measure the t.p.d. effect, a capacitance differential digital micromanometer with sensitivity 4·5 × 10−5N/(m2Hz) was used. The gases investigated were He, Ne, Ar, Xe, H2, D2, N2, CO2, CH4 and SF6. It was discovered that in the intermediate flow regime the thermal-creep flow rate does not depend on the (non-isothermal) tangential momentum accommodation coefficient. From the experimental data on the viscous slip flow regime, the Eucken factors and the accommodation coefficients are calculated. For inert gases the Eucken factor is found to be equal to 2·5 within the experimental error, while the accommodation coefficients differ significantly from unity.
Flow around a circular cylinder near a plane boundary
Authors: Bearman P. W. , Zdravkovich M. M.
Published: April 2006

The flow around a circular cylinder placed at various heights above a plane boundary has been investigated experimentally. The cylinder spanned the test section of a wind tunnel and was aligned with its axis parallel to a long plate and normal to the free stream. It was placed 36 diameters downstream of the leading edge of the plate and its height above the plate was varied from zero, the cylinder lying on the surface, to 3·5 cylinder diameters. The thickness of the turbulent boundary layer on the plate at the cylinder position, but with it removed from the tunnel, was equal to 0·8 of the cylinder diameter. Distributions of mean pressure around the cylinder and along the plate were measured at a Reynolds number, based on cylinder diameter, of 4·5 × 104. Spectral analysis of hot-wire signals demonstrated that regular vortex shedding was suppressed for all gaps less than about 0·3 cylinder diameters. For gaps greater than 0·3 the Strouhal number was found to be remarkably constant and the only influence of the plate on vortex shedding was to make it a more highly tuned process as the gap was reduced. Flow-visualization experiments in a smoke tunnel revealed the wake structure at various gap-to-diameter ratios.
Self-formed straight rivers with equilibrium banks and mobile bed. Part 2. The gravel river
Authors: Parker Gary
Published: April 2006

Rivers are capable of transporting their own bed material without altering their width. However, a naive extension of the threshold theory of canals in coarse alluvium to straight reaches of gravel rivers leads to the stable-channel paradox: transport of bed material is incompatible with a stable width. In this paper singular perturbation techniques are used to obtain a bed stress distribution which allows a mobile bed but immobile banks at bankfull or dominant discharge. This result is used to obtain regime relations for straight rivers with bed and banks composed of coarse gravel.

The analysis, although dependent on a series of approximate assumptions for Reynolds-stress closure and sediment transport, provides reasonable agreement with data.
A numerical study of the deformation and burst of a viscous drop in an extensional flow
Authors: Rallison J. M. , Acrivos A.
Published: April 2006

We study the deformation and conditions for breakup of a liquid drop of viscosity λμ freely suspended in another liquid of viscosity μ with which it is immiscible and which is being sheared. The problem at zero Reynolds number is formulated exactly as an integral equation for the unknown surface velocity, which is shown to reduce to a particularly simple form when Δ = 1. This equation is then solved numerically, for the case in which the impressed shear is a radially symmetric extensional flow, by an improved version of the technique used, for Δ = 0, by Youngren & Acrivos (1976) so that we model the time-dependent distortion of an initially spherical drop. It is shown that, for a given Δ, a steady shape is attained only if the dimensionless group Ω ≡4πGμa/γ lies below a critical value Ωc(Δ), where G refers to the strength of the shear field, a is the radius of the initial spherical drop and γ is the interfacial tension. On the other hand, when Ω > Ωc the drop extends indefinitely along its long axis. The numerical results for Δ = 0·3, 0·5, 1, 2, 10 and 100 are in good agreement with the predictions of the small deformation analysis by Taylor (1932) and Barthès-Biesel & Acrivos (1973) and, at the smaller Δ, with those of slender-body theory (Taylor 1964; Acrivos & Lo 1978).
Similarity treatment of moving-equilibrium turbulent boundary layers in adverse pressure gradients
Authors: Kader B. A. , Yaglom A. M.
Published: April 2006

Dimensional analysis is applied to the velocity profileU(y)of turbulent boundary layers subjected to adverse pressure gradients. It is assumed that the boundary layer is in moving or local equilibrium in the sense that the free-stream velocityU∞ and kinematic pressure gradient α = ρ−1dP/dx vary only slowly with the co-ordinate x. This assumption implies a rather complicated general equation for the velocity gradient dU/dy which may be considerably simplified for several specific regions of the flow. A general family of velocity profiles is derived from the simplified equations supplemented by some experimental information. This family agrees well with almost all existing data on velocity profiles in adverse-pressure-gradient turbulent boundary layers. It may be used for the derivation of a skin-friction law which predicts satisfactorily the values of the wall shear stress at any non-negative value of the pressure gradient. The variation of the boundary-layer thickness with x is also predicted by dimensional considerations.
The motion of a large gas bubble rising through liquid flowing in a tube
Authors: Collins R. , Moraes F. F. De , Davidson J. F. , Harrison D.
Published: April 2006

The theory presented here describes the motion of a large gas bubble rising through upward-flowing liquid in a tube. The basis of the theory is that the liquid motion round the bubble is inviscid, with an initial distribution of vorticity which depends on the velocity profile in the liquid above the bubble. Approximate solutions are given for both laminar and turbulent velocity profiles and have the form
\begin{equation}
U_s = U_c+(gD)^{\frac{1}{2}}\phi(U_c/(gD)^{\frac{1}{2}}),
\end{equation}Us being the bubble velocity, Uc the liquid velocity at the tube axis, g the acceleration due to gravity, and D the tube diameter; ϕ indicates a functional relationship the form of which depends upon the shape of the velocity profile. With a turbulent velocity profile, a good approximation to (1) which is suitable for many practical purposes is
\begin{equation}
U_s = U_s + U_{s0},
\end{equation}Us0 being the bubble velocity in stagnant liquid. Published data for turbulent flow are known to agree with (2), so that in this case the theory supports a well-known empirical result. Our laminar flow experiments confirm the validity of (1) for low liquid velocities.
Two-dimensional analyses related to wave-energy extraction by submerged resonant ducts
Authors: Lighthill James
Published: April 2006

Submerged resonant ducts offer an approach to the design of wave-energy extraction devices consistent with the need for maximum seaworthiness. This paper gives a full account of one type of analysis of these systems, based upon two-dimensional wave hydrodynamics and linearized duct dynamics. The mathematical analyses are given in detail in § 2 while § 1 describes as concisely as possible (i) the assumptions underlying each analysis, (ii) its results and their implications for design, and (iii) any available experimental comparisons.

One theoretical prediction, unexpected when it was first made but since confirmed by experiment (Knott & Flower 1979), is that the effective pressure fluctuations to which a resonant duct responds can be substantially greater than those that would be present at the level of the duct mouth if the duct were absent. Other important predictions are concerned with added mass, radiation damping and the conditions for optimum energy extraction, calculated below for a wide variety of mouth design configurations and internal duct geometries. Broad tentative conclusions from the analyses are given at the end of § 1.
The relative diffusion of a cloud of passive contaminant in incompressible turbulent flow
Authors: Chatwin P. C. , Sullivan Paul J.
Published: April 2006

A problem of major practical interest is the variation with x and t of the statistical properties of Γ(x, t), the distribution of concentration of a contaminant in a cloud containing a finite quantity Q of contaminant, released in a specified way at t = 0 over a volume of order L30. Of particular relevance is the case of relative diffusion (when x is measured throughout each realization relative to the centre of mass of the cloud), when important properties are L(t), the linear dimension of the cloud, C(x, t), the ensemble mean concentration, $\overline{c^2}({\bf x}, t)$, the variance of the concentration, and p(y, t), the distance-neighbour function. Much fundamental work has led to a knowledge of the way L varies with t, but not of the way the other properties vary. Hitherto therefore, prediction of such variation has normally used unjustifiable empirical concepts such as eddy diffusivities, but this is ultimately unsatisfactory, practically as well as theoretically. Hence the exact equations have been used to obtain a quite new description of the structure of a dispersing cloud, which it is hoped will serve as a basis for future practical work.

When κ = 0 (where κ is the molecular diffusivity) the magnitude of p(y, t) is of order Q/L3 for most y, but of order Q/L30 when |y| is very small. By a variety of arguments it is shown that these facts can be explained (for many, if not all, flows) only if the distributions of C and $\overline{c^2}$, as well as that of p, have a core-bulk structure. In the bulk of the cloud C and $\overline{c^2}$ have magnitudes of order Q/L3 and Q2/L30L3 respectively, but there is a core region of thickness decreasing to zero surrounding the centre of mass within which they have much greater magnitudes. In one case, examined in some detail, the magnitudes in the core are of order Q/L30 and Q2/L60.

It is then shown that the core and bulk exist even in the real case when κ ≠ 0. In the real case the core thickness no longer tends to zero but to a constant of order λc, the conduction cut-off length. As a consequence almost entirely of molecular diffusion acting in the core region, the magnitudes of C and $\overline{c^2}$ in both the core and the bulk decay to zero in a way which depends on the details of the fine-scale structure of the velocity field. Several examples of the decay are discussed.
Gravity flow of cohesionless granular materials in chutes and channels
Authors: Savage Stuart B.
Published: April 2006

A constitutive equation appropriate for flow of cohesionless granular materials at high deformation rates and low stress levels is proposed. It consists of an extension and a reinterpretation of the theory of Goodman & Cowin (1972), and accounts for the non-Newtonian nature of the flow as evidenced by Bagnold's (1954) experiments. The theory is applied to analyses of gravity flows in inclined chutes and vertical channels. Experiments were set up in an attempt to generate two-dimensional shear flows corresponding to these analyses. Velocity profiles measured by a technique which makes use of fibre optic probes agree qualitatively with the theoretical predictions, but direct comparison is inappropriate because of unavoidable side-wall friction effects in the experiments. The existing measure of agreement suggests that the most prominent effects have been included in the proposed constitutive relations. Tests in the inclined chute revealed the possible existence of surge waves and granular jumps analogous to hydraulic jumps.
The separation of flow past a cylinder in a rotating system
Authors: Merkine Lee-Or , Solan Alexander
Published: April 2006

The flow past a cylinder bounded by parallel planes in a rotating frame is treated in terms of a nonlinear Stewartson layer. It is shown that separation is strongly dependent on the ratio of the Rossby number to the square root of the Ekman number, covering the whole range from fully attached flow to the classical non-rotating separated flow past a cylinder. The results are in agreement with published experimental observations.
The influence of a third diffusing component upon the onset of convection
Authors: Griffiths R. W.
Published: April 2006

The small amplitude stability analysis for the onset of double-diffusive convection when the density gradient is gravitationally stable is extended to include a third diffusing component. Special attention is given to systems with κ1 [Gt ] κ2, κ3 and Pr [Gt ] κ/κ1, where κi is the molecular diffusivity of the ith component and Pr is the Prandtl number based on the largest of the Ki. It is found that the boundary for the onset of overstability is approximated by two straight lines in a Rayleigh number plane. Small concentrations of a third property with a smaller diffusivity can have a significant effect upon the nature of diffusive instabilities, the magnitude of this effect being proportional to κ1/Ki. Oscillatory and direct ‘salt-finger’ modes are found to be simultaneously unstable under a wide range of conditions when the density gradients due to the components with the greatest and smallest diffusivities are of the same sign.
Energy and momentum integrals for progressive capillary-gravity waves
Authors: Crapper G. D.
Published: April 2006

Definitions of energy density, energy flux and momentum flux for capillary—gravity waves are derived by integration of the equations of motion and also by Whitham's averaged Lagrangian method. We then confirm recent results due to Hogan (1979) both in the general case and in the case of pure capillary waves. Comparison with the Lagrangian results also allows us to give general definitions of ‘wave action density’ and ‘wave action flux’.
The hydrodynamics of flagellar propulsion: helical waves
Authors: Higdon J. J. L.
Published: April 2006

The swimming of a micro-organism by the propagation of helical waves on a long slender flagellum is analysed. The model developed by Higdon (1979) is used to study the motion of an organism with a spherical cell body (radius A) propelled by a cylindrical flagellum (radius a, length L).

The average swimming speed and power consumption are calculated for helical waves (amplitude α, wavenumber k). A wide range of parameter values is considered to determine the optimal swimming motion. The optimal helical wave has ak ≈ 1, corresponding to a pitch angle of 45°. The optimum number of waves on the flagellum increases as the flagellar length L/A increases, such that the optimum wavelength decreases as L/A increases. The efficiency is relatively insensitive to the flagellar radius a/A. The optimum flagellar length is L/A ≈ 10.

The results are compared to calculations using two different forms of resistance coefficients. Gray-Hancock coefficients overestimate the swimming speed by approximately 20% and underestimate the power consumption by 50%. The coefficients suggested by Lighthill (1976) overestimate the swimming speed for large cell bodies (L/A < 15) by 20% and underestimate for small cell bodies (L/A > 15) by 10%. The Lighthill coefficients underestimate the power consumption up to 50% for L/A < 10, and overestimate up to 25% for L/A > 10. Overall, the Lighthill coefficients are superior to the Gray-Hancock coefficients in modelling swimming by helical waves.
On the formation of bubbles in gas-particulate fluidized beds
Authors: Fanucci Jerome B. , Ness Nathan , Yen Ruey-Hor
Published: April 2006

The method of characteristics is applied to the nonlinear equations describing two-phase flow in a fluidized bed. The method shows how a small disturbance changes with time and distance and can, eventually, produce a flow discontinuity similar to a shock wave in gases. The parameters entering the analysis are the amplitude of the initial disturbance, the wavelength of the original disturbance, the particulate pressure function, the particulate size, the uniform fluidization voidage, the uniform fluidization velocity, the fluid viscosity, the particulate density, and the fluid density. A parametric study shows that the following factors delay shock formation: a decrease in particulate size, an increase in bed density, an increase in fluid viscosity, and a decrease in particulate density. Experimental data on bubble formation in gas-particulate fluidized beds show that these same factors delay bubble formation. It is concluded, therefore, that the shock front and the bubble front are one and the same thing.
Conditional sampling study of the turbulent wake of a cylinder. Part 1
Authors: Fabris Gracio
Published: April 2006

The far turbulent wake of a slightly heated cylinder was studied using our specially developed four-wire probe and digital processing of signals obtained. The processing method included a simultaneous solution of full nonlinear response equations for the four sensors yielding values of instantaneous velocity vector and temperature. The accuracy of results was improved substantially by the subtraction of free-stream velocity and temperature variations, first-order corrections for the d.c. drift of the signals, the elimination of 60 Hz related noise, and instantaneous correction for the streamwise displacement between the sensor wires. A low temperature threshold was used to discriminate between turbulent and potential flow.

The frequency of crossing of the turbulent-potential interface and statistics of turbulent and potential zone intervals are presented. Conditionally sampled fluctuating velocity and temperature fields are given for turbulent and potential zones as well as for a fluid at the downstream and upstream interface of the turbulent zones. Averaging was done with respect to conventional (Reynolds) as well as local zone or point means. The results on turbulence structure up to second-order correlations are presented in this paper.

It is hoped that the data will be useful for those interested in methods of prediction of turbulence, especially those based on the consideration of large structures. Researchers more interested in the physical phenomena involved might also find the data suitable for further analysis and interpretation.
Numerical calculations of steady gravity-capillary waves using an integro-differential formulation
Authors: Rottman James W. , Olfe D. B.
Published: April 2006

A new integro-differential equation is derived for steady free-surface waves. Numerical solutions of this equation for periodic gravity-capillary waves on a fluid of infinite depth are presented. For the two limiting cases of gravity waves and capillary waves, our results are in excellent agreement with previous calculations. For gravity-capillary waves, detailed calculations are performed near the wave-number at which the classical second-order perturbation solution breaks down. Our calculations yield two solutions in this region, which in the limit of small amplitudes agree with the results obtained by Wilton in 1915; one solution has the small amplitude behaviour of a gravity wave and the other that of a capillary wave, but the numerical results show that at large amplitudes both waves have the characteristics of capillary waves. The calculations also show that the wavenumber range in which two solutions exist increases with increasing wave height.