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M J Greenall

Publications and source records attributed to M J Greenall.

At least 19 recordsLinked to original sources
PubMed2006

Glass transition in fullerenes: mode-coupling theory predictions.

We report idealized mode-coupling theory results for the glass transition of ensembles of model fullerenes interacting via phenomenological two-body potentials. Transition lines are found for C60, C70, and C96 in the temperature-density plane. We argue that the observed glass transition behavior is indicative of kinetic arrest that is strongly driven by the interparticle attraction in addition to excluded-volume repulsion. In this respect, these systems differ from most standard glass-forming liquids. They feature arrest that occurs at lower densities and that is stronger than would be expected for repulsion-dominated hard-sphere-like or Lennard-Jones-type systems. The influence of attraction increases with increasing the number of carbon atoms per molecule. However, unrealistically large fullerenes would be needed to yield behavior reminiscent of recently investigated model colloids with strong short-ranged attraction (glass-glass transitions and logarithmic decay of time-correlation functions).

Journal Article↗
PubMed2006

Sensitivity of arrest in mode-coupling glasses to low-q structure.

We quantify, within mode coupling theory, how changes in the liquid structure affect that of the glass. Apart from the known sensitivity to the structure factor S(q) at wave vectors around the first sharp diffraction peak q0, we find a strong (and inverted) response to structure at wave vectors below this peak: an increase in S(q0/2) lowers the degree of arrest over a wide q-range. This strong sensitivity to "caged cage" packing effects, on length scales of order 2d, is much weaker in attractive glasses where short-range bonding dominates the steric caging effect.

Journal Article↗
PubMed2005

Langer's axillary arch: anatomy, embryological features and surgical implications.

Langer's arch is identified in up to 7% of axillary explorations; in a three-month period we identified three individuals among forty-six patients undergoing axillary surgery with this abnormality. Langer's arch is a muscular-tendinous structure that usually extends from latissimus dorsi to pectoralis major muscle. The purpose of this article is to describe the embryological derivation of this muscular variant from the panniculus carnosus and to define its anatomical features. The clinical implications both symptomatically and as an unexpected finding during axillary dissection, are also discussed.

Axilla↗
PubMed2004

Interfacial structure at a two-dimensional wedge filling transition: Exact results and a renormalization group study.

Interfacial structure and correlation functions near a two-dimensional wedge filling transition are studied using effective interfacial Hamiltonian models. An exact solution for short range binding potentials and results for Kratzer binding potentials show that sufficiently close to the filling transition a new length scale emerges and controls the decay of the interfacial profile relative to the substrate and the correlations between interfacial positions above different positions. This new length scale is much larger than the intrinsic interfacial correlation length, and it is related geometrically to the average value of the interfacial position above the wedge midpoint. The interfacial behavior is consistent with a breather mode fluctuation picture, which is shown to emerge from an exact decimation functional renormalization group scheme that keeps the geometry invariant.

Journal Article↗
PubMed2003

Fluid adsorption near an apex: covariance between complete and critical wetting.

Critical wetting is an elusive phenomenon for solid-fluid interfaces. Using interfacial models we show that the diverging length scales, which characterize complete wetting at an apex, precisely mimic critical wetting with the apex angle behaving as the contact angle. Transfer matrix, renormalization group, and mean-field analysis show that this covariance is obeyed in 2D and 3D and for long- and short-ranged forces. This connection should be experimentally accessible and provides a means of checking theoretical predictions for critical wetting.

Journal Article↗
PubMed1994

Current controversies in the surgical management of breast cancer.

BACKGROUND: Great advances have occurred in the surgical management of breast cancer during the past 2 decades, though areas of controversy still remain. The surgical treatment of breast cancer relates to management of the breast and of the axillary nodes. Areas of controversy relate to methods of breast conservation after preoperative chemotherapy for locally advanced disease. The ideals of such treatment are described and the various methods by which such results may be obtained are discussed. The importance of conservation of the nipple-areolar complex is stressed, and the various methods of reconstruction by which this can be achieved are discussed. The role of surgery to the axilla is also discussed, with particular reference to axillary sampling. Data relating to the control of axillary disease treated by irradiation and that obtained after surgery are compared. Current controversies: Breast conservation, partial and subcutaneous mastectomy, reconstruction (using implants, prostheses and myocutaneous flaps), the management of axillary disease and the role of adjuvant therapy are discussed.

Axilla↗
PubMed1991

Gynaecomastia.

This paper reviews the development of excess breast tissue in the male. Gynaecomastia is a common problem and may have a physiological or pathological basis. It can be dealt with in most cases by reassurance or simple surgery.

Adolescent↗
PubMed1989

Lipogenesis by isolated human apocrine sweat glands: testosterone has no effect during long-term organ maintenance.

Lipid synthesis by freshly isolated human apocrine glands has been measured by the incorporation of [U-14C] acetate. Incorporation is linear over 6 h at 1010 +/- 282 pmol/mg wet weight/h (n = 11; mean +/- sem). The lipid classes, as percentages of the total lipid synthesized, were found by TLC to be cholesterol 12.3 +/- 2.0, mono-glycerides 7.5 +/- 1.5, 1,2 di-glycerides 3.0 +/- 0.9, 1,3 di-glycerides 3.5 +/- 0.5, tri-glycerides 28.4 +/- 1.8, free fatty acids 2.0 +/- 0.4, lysolecithin 15.4 +/- 3.9, sphingomyelin 9.9 +/- 4.3, phosphatidyl-choline 8.4 +/- 0.4, phosphatidyl-ethanolamine -inositol and -serine 1.8 +/- 0.1, phosphatidic acid and cardiolipin 3.3 +/- 0.5, and unidentified 3.3 +/- 0.5 (mean +/- sem, n = 5). Glands were maintained on permeable supports. After 10 d maintenance, electron microscopy showed that the cellular architecture had been preserved, that the ATP contents were the same as in freshly isolated glands, and that [U-14C] acetate incorporation was not significantly altered at 851 +/- 237 pmol/mg/h (n = 18). The addition of 3 microM testosterone had no effect on acetate incorporation at 844 +/- 231 pmol/mg/h (n = 18). The lipid classes and their proportions were similar to the values for fresh glands after 10 d maintenance both with and without testosterone.

Acetates↗
PubMed1987

Reduction of the surgical excision rate in benign breast disease using fine needle aspiration cytology with immediate reporting.

Patients attending a breast clinic in two different periods were studied. In the first period fine needle aspiration cytology (FNAC) was not available and in the second it was used on all discrete solid breast lumps and reported immediately in the clinic. With the use of FNAC the overall surgical excision rate for discrete solid lumps was reduced from 83 per cent to 41 per cent and the excision rate in patients with benign disease was reduced from 74 per cent to 23 per cent (P less than 0.001). All patients with breast cancer in the second period had malignant cytology and no patient with benign or acellular cytology has been shown, after a minimum follow-up period of 18 months, to have breast cancer. Using FNAC with immediate reporting, the number of operations performed in patients with benign breast disease can be safely reduced.

Adult↗
PubMed1987

Fine needle aspiration cytology, with immediate reporting, in the outpatient diagnosis of breast disease.

One hundred and fifty one new patients attending a breast clinic over a 6 month period underwent fine needle aspiration cytology (FNAC), with immediate reporting of the smears in the clinic. Thirty nine smears (25.8%) were classified as unequivocally malignant, 10 (6.6%) as being suspicious of malignancy, 61 (40.3%) as benign and 41 (27.1%) were acellular. There were no false positive diagnoses and only one false negative cytological diagnosis of breast cancer [corrected]. Immediate reporting of results enabled the diagnosis to be discussed with the patient at the first attendance and allowed improved surgical management of both benign as well as malignant breast disease.

Adult↗
PubMed1986

Recurrent epidermoid cancer of the anus.

Of 83 patients with recurrent epidermoid cancer of the anus, 67 had tumors in the anal canal and 16 had tumors at the anal margin. Local pelvic or perineal recurrence after abdominoperineal resection of tumors in the canal had a poor prognosis. Median survival after combination chemotherapy and megavoltage irradiation was 14 months. With irradiation alone, median survival was 7 months, although nearly half of these patients had been treated with orthovoltage techniques. Untreated patients with visceral metastases had a median survival of 8 months, but no improvement in survival was seen after treatment with chemotherapy. In contrast, patients who had metastases in inguinal lymph nodes had a 55% 5-year survival rate after inguinal dissection. Patients with tumors at the anal margin did not have visceral metastases. This is an important difference between tumors arising in the canal and those arising at the anal margin. Local excision was satisfactory treatment for 90% of the patients who had local recurrence in the perianal skin; abdominoperineal resection was rarely required. Inguinal lymph node metastases from margin cancer are uncommon, but three of five such patients survived 5 years after groin dissection. A combination of 5-fluorouracil, mitomycin C, and radiation therapy was used for patients with pelvic recurrence after abdominoperineal resection of epidermoid cancer of the anal canal. In this study, there was no evaluation of the role of megavoltage irradiation alone at the recommended doses of 5500 to 6000 rad for these patients. Some patients with visceral metastases respond to combination chemotherapy, but median survival is not improved; evaluation of new chemotherapeutic regimens is required. Patients with canal tumors metastatic to inguinal nodes should be treated by groin dissection as their prognosis is relatively good. Local recurrence of tumors at the anal margin can be satisfactorily treated by further local excision; those patients with margin tumors metastatic to inguinal nodes require groin dissection.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1986

Chemotherapy for soft tissue sarcoma.

Adriamycin is the only active single agent for patients with metastatic sarcoma; combination chemotherapy regimens that omit Adriamycin are ineffective in adults. Despite early success with CYVADIC, there have been recent doubts regarding its efficacy. No other chemotherapeutic combination has provided consistently better results than CYVADIC. As complete responses occur in less than 15 per cent of patients there is a need for further evaluation of new regimens. It is necessary to evaluate new regimens in prospective, randomized studies. Response criteria should be consistent and reproducible. Attenuation schedules and data relating to the total administered dosage should be provided. It would also be beneficial to analyze prognostic variables so that patients liable to an unfavorable outcome could be identified before commencement of treatment.

Antineoplastic Combined Chemotherapy Protocols↗