bluuebunny/crossref_metadata_2025 huggingface dataset:
Maternal posture in second stage and fetal acid base status
Authors: JOHNSTONE F. D. , ABOELMAGD M. S. , HAROUNY A. K.
Published: August 2005

Summary. The effect of position during the second stage on outcome was studied in 58 women, with no exclusions because of pregnancy complications or signs of fetal distress, who were randomly allocated to have the second stage conducted in either the dorsal or 15° lateral tilt position. All the women were of parity 0 or 1 and the two groups were well matched except for gestational age at delivery. There were no differences in clinical outcome between the two groups, but overall the dorsal group had lower cord artery pH values (P<0·05), higher Pco2 (P<0·01) and a greater base deficit, but not significantly so. pH and base deficit were similar in both groups where the second stage did not last >15 min. Thereafter, there was a trend to decreasing pH and increasing base deficit with increasing length of second stage in the dorsal group, but not in the tilt group though this did not reach statistical significance. Low Apgar scores, complicated pregnancy and first pregnancy were each associated with significantly lower pH levels. Prolonged placement of the patient in the flat dorsal position should be avoided in second stage, though a suitable alternative under the conditions described has not been defined.
The effect of severe pre‐eclampsia on the pancreas: changes in the serum cationic trypsinogen and pancreatic amylase
Authors: HAUKLAND HANNE HUSOM , ØIAN PAL , MALTAU JAN M. , FLORHOLMEN JON , BURHOL PER G.
Published: August 2005

Summary. In 13 patients with severe pre‐eclampsia mean serum concentrations of cationic trypsinogen and amylase were statistically significantly higher at 64ng/ml and 1·6 μmol/1, respectively, than the corresponding mean serum concentrations in 30 normal pregnancies, 22 ng/ml and 1·1 μmol/1 respectively. These rises exceeded the expected increased values due to the slight reduction of the renal function in the pre‐eclamptic patients, and therefore indicate a concomitant injury of the pancreas.
Salpingoscopy: a new pre‐operative diagnostic tool in tubal infertility
Authors: BROSENS I. , BOECKX W. , DELATTIN Ph. , PUTTEMANS P. , VASQUEZ G.
Published: August 2005

Summary. Endoscopy of the fallopian tube allows examination of the tubal mucosa in subfertile patients. Clinical and morphological studies have shown a high correlation between the appearance of the tubal mucosa and the ultimate outcome in terms of pregnancies. Salpingoscopy was originally performed during laparotomy for reconstructive tubal surgery. The present study describes the use of a rigid 3 mm telescope passed along the channel of the operating laparoscope to assess the mucosa of the infundibulum and ampullary segment. Lesions of the infundibulum and ampullary segment have been detected in patients with apparently normal tubes on the hysterosalpingogram and at laparoscopy. The extent of the mucosal lesions can be assessed preoperatively in patients with tubal adhesions, tubo‐cornual or isthmic lesions and hydrosalpinges.
Endocrine effects of ovarian electrocautery in patients with polycystic ovarian disease
Authors: GJøNNÆSS HALVARD , NORMAN NILS
Published: August 2005

Summary. The mechanism by which ovarian electrocautery induces regular ovulatory cycles was studied in 16 women with polycystic ovarian disease (PCO) and compared with 25 normal fertile women who were undergoing sterilization by tubal electrocautery. Gonadotrophins (LH and FSH), prolactin, androgens, oestrogens, 17‐hydroxy‐progesterone and progesterone were determined immediately before operation and 24 h later. Following the sampling of blood for these tests, 100 μg of gonadotrophin releasing hormone (GnRH) was given intravenously and the LH and FSH responses were measured at 30 min. In the PCO‐group, these tests were repeated after the first induced ovulatory cycle. After operation, LH increased only in the patients with PCO and this increase was associated with an enhanced response to GnRH, FSH showed a similar response to GnRH, also confined to the PCO‐group. These pituitary responses are best explained by a change in ovarian feedback induced by the direct electrocautery of the glands in the PCO‐group. There was little change in serum oestrogen. Prolactin showed an increment in all cases and serum androgens were reduced in all groups, most pronounced in the PCO patients, possibly as a result of the stress of operation. An ovarian factor—released or reduced by the electrocautery—seems to be responsible for the changes.
The influence of age on prognosis in carcinoma of the cervix
Authors: SMALES E. , PERRY C. M. , ASHBY M. A. , BAKER J. W.
Published: August 2005

Summary. Of 385 new patients with invasive carcinoma of the cervix FIGO stages IB—IV treated between 1970–1984 inclusive, 11% (43 patients) were aged ≤35 years. During the period studied there was a gradual rise in the proportion of such young women from 2% for the triennium 1970–1972 to 18% for 1982–1984. In women aged ≤35 years early stage disease predominated, 72% presenting with stage IB disease, compared with 29% in the older age group. For FIGO stage IB there was no significant difference in actuarial survival between younger and older patients (P>0·1), both age groups having a 5‐year survival rate of 81%. Similarly for FIGO stage II there was no difference in actuarial survival (P>0·1) between younger and older patients who had 5‐year survival rates of 66% and 63% respectively. In our experience the incidence of invasive carcinoma of the cervix in young women is rising, but stage for stage their survival is similar to that of older women.
Recurrent acute leg cellulitis after hysterectomy with pelvic lymphadenectomy
Authors: DANKERT J. , BOUMA J.
Published: August 2005

Summary. Recurrent acute leg cellulitis known to occur in patients with impaired venous or lymphatic circulation was surveyed prospectively in 270 patients after radical hysterectomy with pelvic lymphadenectomy and in 66 patients after hysterectomy with pelvic lymphadenectomy from 1977 to 1985. Among them, six (2%) and three (4%) patients experienced a total of 17 episodes of acute leg cellulitis, respectively. Analysis showed that postoperative percutaneous radiation therapy of the pelvic area was a highly significant risk factor. Penicillin prophylaxis is recommended for patients experiencing recurrent attacks.
Pregnancy following induced abortion: maternal morbidity, congenital abnormalities and neonatal death
Authors: FRANK P. I. , KAY C. R. , SCOTT L. M. , HANNAFORD P. C. , HARAN D.
Published: August 2005

Summary. In a prospective cohort study of the long‐term sequelae of induced abortion, a comparison is made between a group of 6418 women who had an induced abortion (cases) and a control group of 8059 women recruited with an unplanned pregnancy which was not terminated with an induced abortion (controls). The present paper reports on 729 cases and 1754 controls who had a post‐recruitment pregnancy. In general, prior induced abortion had no material effect on the rate of pregnancy‐related morbidity, nor on the rate of congenital abnormalities and neonatal death in the offspring. There was, however, a significant difference in two specific conditions. In the post‐index pregnancy in the cases there was an increased relative risk (RR 2·26) of the occurrence of urinary tract infection and a decreased risk (RR 0·25) of pregnancy‐related anaemia.
Evaluation of the WHO criteria for 75 g oral glucose tolerance test in pregnancy
Authors: LI DOMINIC F. H. , WONG VIVIAN C. W. , O'HOY KATHERINE M. , MA H. K.
Published: August 2005

Summary. A group of pregnant women at high risk of developing diabetes in pregnancy had paired oral glucose tolerance tests (OGTT) using a 100 g load followed by 75 g load. When the World Health Organization (WHO) criteria and the National Diabetes Data Group (NDDG) criteria were compared, the 2‐h plasma glucose value after the 100 g load was the most discriminative in differentiating those with normal glucose tolerance, impaired glucose tolerance and gestational diabetes mellitus. When only the 2‐h plasma glucose values were assessed, the WHO test (75 g: 8 mmol/1) agreed with the NDDG test (100 g load: 9·2 mmol/1) in the diagnosis of glucose intolerance in 60% of subjects only. Using the same criteria at 2‐h (8 mmol/1) the agreement between these tests was 47%. Reducing the glucose load from 100 g to 75 g produced a reduced glucose response in 49% of the subjects, with a significant decrease in the area under the glucose response curve.
Is treatment needed for mild impairment of glucose tolerance in pregnancy? A randomized controlled trial
Authors: LI DOMINIC F. H. , WONG VIVIAN C. W. , O'HOY KATHERINE M. K. Y. , YEUNG C. Y. , MA H. K.
Published: August 2005

Summary. The study was designed to identify those pregnant women who are diagnosed as having gestational diabetes by National Diabetes Data Group (NDDG) criteria, but normal glucose tolerance (NGT) or impaired glucose tolerance (IGT) by the World Health Organization (WHO) criteria, and to test whether treatment changed the perinatal outcome in those with NGT and IGT. The 216 women with an abnormal 100 g oral glucose tolerance test (OGTT) using NDDG criteria were subjected to a 75 g OGTT. Using the WHO criteria, 111 women (51%) had NGT, 98 (45%) had IGT and 7 (3%) had frank diabetes mellitus. Those with NGT and IGT were randomized into control and treatment groups. The perinatal outcome in these two groups was comparable whether the NGT and IGT groups were analysed together or separately except, that in those who were treated for IGT, smaller babies were born one week earlier than in the control group (3407 g vs 3110g, P<0·01). This suggests that the WHO criteria can safely replace the 100 g OGTT with substantial savings in manpower, money and patients' time.
The predictive value of fetal breathing movements in the diagnosis of preterm labour
Authors: AGUSTSSON PALL , PATEL NAREN B.
Published: August 2005

Summary. A real time ultrasound investigation was performed on 64 patients who presented in threatened preterm labour. Fetal breathing movements (FBM) were absent in 17 patients, all of whom were delivered within 56 h. FBM were present in 47 patients of whom five were delivered within 56 h from examination and four of these had spontaneous rupture of membranes and/or chorioamnionitis. In 33 the pregnancy continued for at least 1 week. Two of the fetuses with false negative results showed a distinct breathing pattern different from the rest of the study group. This suggests that pattern recognition of fetal breathing might improve the specificity of this investigation.
Postpartum pelvic arthropathy with unusual features
Authors: DRIESSEN FRITS
Published: August 2005

Summary. Eleven patients seen in Malawi are described with a syndrome of postpartum pelvic arthropathy. They complained of severe pain mainly located in the symphysis pubis and all were unable to walk. The following unusual features were noted: the absence of obstetric trauma, a symptom‐free interval between the delivery and the onset of the syndrome, the absence of gross widening of the symphysis pubis and the lack of abnormal mobility in the same joint. It is speculated that the syndrome described is not caused by rupture of the symphysis or softening under the influence of hormones but by swelling inside the intact fibrous confines of the joint.
Apgar score, meconium and acidaemia at birth in small‐for‐gestational age infants born at term, and their relation to neonatal neurological morbidity
Authors: DIJXHOORN M. J. , VISSER G. H. A. , TOUWEN B. C. L. , HUISJES H. J.
Published: August 2005

Summary. Neonatal neurological morbidity was studied in relation to Apgar score, meconium stained amniotic fluid and acidaemia at birth in 247 small‐for‐gestational age (SGA) maturely born infants. SGA infants, and especially the severely SGA infants and those born abdominally, showed higher rates of neurological morbidity, acidaemia and meconium stained amniotic fluid than appropriate‐for‐gestational age (AGA) controls. The examined indicators of asphyxia at birth showed slightly higher correlation coefficients with the ‘neonatal neurological optimality score’(NNOS) in SGA, than in AGA term infants, but the percentage of explained variance was low, except in the 23 infants born abdominally. In this group poor neurological outcome was restricted to the 14 infants who showed signs of fetal hypoxaemia diagnosed by decelerative fetal heart rate (FHR) patterns. In 11 of them, FHR decelerations occurred antepartum. These FHR abnormalities appear to be better predictors for the neonatal neurological outcome than indicators of asphyxia at birth.
Outcome of in‐vitro fertilization and embryo transfer after different regimens of ovarian stimulation
Authors: IMOEDEMHE D. A. G. , SHAW R. W. , BERNARD A. , INGLIS M.
Published: August 2005

Summary. Sixty‐eight women with bilateral tubal disease and fertile male partners underwent ovarian stimulation in 187 cycles for IVF after randomization to different ovulation induction regimens. All patients initially received 150 mg clomiphene citrate on days 5–9, this regimen induced sufficient stimulation in a smaller proportion of patients than the two other regimens used subsequently which included clomiphene in combination with human menopausal gonadotrophins (hMG). The fertilization rate was significantly reduced (52–4%) in oocytes collected from cycles stimulated with hMG alone (in a small sub‐group of poor responders) compared with a rate of 64·1–66·4% in cycles stimulated with clomiphene alone or in combination with hMG. Embryonic development 44–48 h after insemination was significantly retarded when clomiphene alone was utilized but a higher proportion of fragmented or abnormal embryos was observed after stimulation with hMG alone. In 118 cycles embryo transfer was performed and 20 pregnancies were established, a pregnancy rate of 16·9%. All but two pregnancies were established when two or more embryos were transferred and when the embryos were at the 4‐cell or later stage of development. The regimen of clomiphene in combination with 150 i.u. hMG resulted in significantly greater numbers of oocytes recovered and embryos available per patient for transfer than the other two regimens studied.
Negative cone biopsies after colposcopy and their prediction
Authors: LUESLEY D. M. , WOODMAN C. B. J. , WADE‐EVANS T. , JORDAN J. A.
Published: August 2005

Summary. A retrospective study of 899 cone biopsies revealed significantly more cones containing no dysplastic epithelium in patients who had a prior colposcopic assessment compared with those who had not been so assessed. A case‐control study of 48 ‘negative’ cones, 47 cones containing intraepithelial neoplasia (CIN), 44 microcarcinoma containing cones and 27 occult Ib containing cones has allowed five variables to be identified which can predict the presence of dysplastic or neoplastic tissue in the cone specimen. These variables include a colposcopic suspicion of invasion; a positive or worse pre‐cone smear; two severely dyskaryotic smears within a 12‐month observation period, previous abnormal histology and previous treatment for CIN. Using these criteria, 44% of ‘negative’ cones could be avoided without overlooking any cases of microcarcinoma or occult carcinoma.
Immunoscintigraphy of endometriosis
Authors: KENNEDY S. H. , MOJIMINIYI O. A. , SOPER N. D. W. , SHEPSTONE B. J. , BARLOW D. H.
Published: August 2005

Summary. Twenty‐eight women with suspected endometriosis or infertility, or both, received radiolabelled monoclonal antibody OC‐125 F(ab′)2 fragments before surgery in a study to determine whether foci of pelvic endometriosis could be displayed with immunoscintigraphy. Immunoscintigraphy was positive in 22 women (16 with endometriosis, two with pelvic adhesions, one with pelvic inflammatory disease and one with normal pelvic findings) and negative in five women (two with endometriosis and three with normal pelvic findings). One woman developed a hypersensitivity reaction and, therefore, did not receive the radiolabelled fragments. The method had 89% sensitivity and 33% specificity for the diagnosis of endometriosis; it had 91% sensitivity and 60% specificity for the diagnosis of benign pelvic disease.
The implications of introducing the symphyseal‐fundal height‐measurement. A prospective randomized controlled trial
Authors: LINDHARD A. , NIELSEN P. V. , MOURITSEN L. A. , ZACHARIASSEN A. , SØRENSEN H. U. , ROSENØ H.
Published: August 2005

Summary. A total of 1639 women attending the antenatal clinic of Gentofte University Hospital, Copenhagen, during 1986–1987 was randomized into a symphyseal fundal (SF)‐group and a control group. The women in the SF‐group had their fundal height measured from the 29th week until delivery. The measurements were used along with the other usual screening procedures. The SF‐measurements were not found helpful in the prediction of small‐for‐gestational‐age infants and no significant differences were found between the two groups regarding the number of interventions, additional diagnostic procedures, or the condition of the newborns.
New design rigid and soft vacuum extractor cups: a preliminary comparison of traction forces
Authors: HOFMEYR G. JUSTUS , GOBETZ LAWRENCE , SONNENDECKER ERNST W. W. , TURNER MARTIN J.
Published: August 2005

Summary. Women due for vacuum extraction were randomly allocated to delivery using one of two soft cups (Silc or Silastic) or two new design rigid cups (New Bird or O'Neil). Traction forces were recorded continuously and higher values were reached with the rigid than the soft cups (median 15.8, range 7.5.19.7 vs 11.1, 7.2.15.1 kg, P < 0.01). Selection of the most appropriate vacuum cup for each clinical situation should take into account that the flexible cups are associated with less cosmetic disfigurcment but have a lower capacity for traction.
Preliminary Doppler studies on the uterine artery and myometrium in trophoblastic tumours requiring chemotherapy
Authors: LONG M. G. , BOULTBEE J. E. , BEGENT R. H. J. , HANSON M. E. , BAGSHAWE K. D.
Published: August 2005

Summary. The uterine circulation in 38 patients with invasive mole or choriocarcinoma were investigated using Doppler ultrasound. Twenty‐six non‐pregnant and 23 pregnant volunteers were assessed in a similar fashion to act as control groups. The pulsatility indices were significantly lower in the patients with trophoblastic disease when compared with the non‐pregnant and pregnant groups (Student's t‐test; P<0.001 and P<0.02 respectively). The uterine circulation in persistent trophoblastic diseases shows a characteristic Doppler profile suggesting the presence of large low resistance blood vessels. This may be useful in the initial assessment of these tumours before cytotoxic chemotherapy.
Accuracy of ultrasound measurements of female pelvic organs
Authors: SAXTON D. W. , FARQUHAR C. M. , RAE T. , BEARD R. W. , ANDERSON M. C. , WADSWORTH J.
Published: August 2005

Summary. Uterine size, endometrial thickness and ovarian volume were measured ultrasonically and the results compared with caliper measurements made shortly afterwards at the time of total hysterectomy and bilateral salpingo‐oophorectomy. The results establish the validity of ultrasound measurements. Histological studies also confirmed the diagnosis made with ultrasound of polycystic ovaries in women complaining of pain due to pelvic congestion.
Apparent liver blood flow during pregnancy: a serial study using indocyanine green clearance
Authors: ROBSON S. C. , MUTCH E. , BOYS R. J. , WOODHOUSE K. W.
Published: August 2005

Summary. Serial measurements of apparent liver blood flow and cardiac output were performed in 12 women at 12–14, 24–26 and 36–38 weeks of pregnancy and then at 10–12 weeks after delivery. Apparent liver blood flow was calculated from indocyanine green clearance. Cardiac output was measured by Doppler and cross‐sectional echocardiography at the aortic valve. Postnatal apparent liver blood flow was 1.811/min and no significant change was demonstrated during pregnancy. In contrast cardiac output decreased from 7.461/min at 36–38 weeks gestation to 4.901/min after delivery. Apparent liver blood flow accounted for 24% of cardiac output during pregnancy. This increased to 37% after delivery.
Classroom Learning, Teaching, and Research: A Task‐Based Perspective
Authors: PICA TERESA
Published: August 2005

In an increasing number of second language (L2) classrooms, teachers and researchers are taking on new roles and responsibilities. From these new perspectives, they are developing similar concerns about L2 learning processes, which they typically express in ways that reflect their different backgrounds and goals. To support learning, teaching, and research in the L2 classroom, researchers and teachers have attempted to develop activities that both address their concerns and accommodate their differences on a long‐term basis. This article reflects my participation as a researcher in this context and presents the ways in which the teachers and students with whom I have worked have turned to information gap tasks to serve many of our needs. The first part of the article describes the contributions of information gap tasks as seen from our learning, teaching, and research perspectives. The second part describes the issues and challenges we have faced in integrating and implementing them. Then the third part presents an approach that we have developed for designing information gap tasks both as authentic activities for teaching and learning and as reliable instruments for research. Examples of our tasks are provided, together with excerpts from the discourse of their classroom implementation. These excerpts reveal the effectiveness of the tasks in drawing students' attention to form, function, and meaning in ways that we considered vital to students' L2 learning.
Investigating the Psychological and Emotional Dimensions in Instructed Language Learning: Obstacles and Possibilities
Authors: DEWAELE JEAN–MARC
Published: August 2005

In this article I put forth the core argument that Second Language Acquisition (SLA) needs to account for the psychological and emotional dimensions of second language (L2) learning, but that a number of epistemological and methodological difficulties must be surmounted before this new research program can be a reality. To illustrate my arguments, I examine in depth 2 research programs developed by my colleagues and me over the last decade: research on extraversion as a psychological variable investigated within the tradition of individual differences in SLA, and research on the expression of emotion in the L2. Throughout the article, I argue against research isolationism and for more interdisciplinarity in the field of instructed SLA. I contend that research on instructed SLA would benefit from an increased methodological and epistemological diversity and that a focus on affect and emotion among researchers might inspire authors of teaching materials and foreign language teachers to pay increased attention to the communication of emotion and the development of sociocultural competence in a L2.
Beyond Orality: Investigating Literacy and the Literary in Second and Foreign Language Instruction
Authors: KERN RICHARD , SCHULTZ JEAN MARIE
Published: August 2005

This article argues for a context‐sensitive, integrative approach to research on reading, writing, and related text‐based practices in second language acquisition (SLA). The approach views literacy not as universal psycholinguistic processes but as constellations of social, cognitive, and linguistic practices that vary with situational and cultural contexts and that are learned through apprenticeship. Many of the phenomena that have been explored in SLA research under the rubric of the cognitive (e.g., learning strategies, reading strategies, writing strategies, transfer, etc.) need to be explored simultaneously from the perspective of the social (i.e., their functional significance within particular contexts of language use). Within the context of socially and culturally embedded literacy, the role of the literary, the traditional material for the teaching of reading and writing in many university‐level foreign language classrooms, takes on new importance in terms of its potential impact on the development of second language literacy. Methodologically, this agenda places key importance on qualitative approaches, and highlights the need for a great deal more research on semiotics in written communication practices.
Epistemology, Politics, and Ethics in Sociocultural Theory
Authors: THORNE STEVEN L.
Published: August 2005

This article describes the history and continuing development of Vygotsky‐inspired sociocultural theories (SCT) and their application in second and foreign language research. In particular, I emphasize the intellectual traditions out of which SCT emerged and the relation of SCT to other critical scholarship. The discussion includes long‐standing as well as recent conceptual and methodological innovations in SCT research, the philosophical entailments of SCT in regard to epistemology and ethical issues, and a select review of SCT second language studies.
For What and for Whom Is Our Research? The Ethical as Transformative Lens in Instructed SLA
Authors: ORTEGA LOURDES
Published: August 2005

In this article, I argue for adopting an ethical lens that interrogates our ends and purposes when generating research on second language learning and teaching, in light of concerns surrounding questions about the uses and users of our work. Such an ethical lens would help us transform our methodological and epistemological debates and would also strengthen the social and educational worth of the research that is generated by diverse second language acquisition (SLA) communities. I offer 3 normative principles for disciplinary discussion: The value of research is to be judged by its social utility; value‐free research is impossible; and epistemological diversity is a good thing. For each principle, I present the thrust of the argument and illustrate it by reference to 1 or more selected problems central to SLA research programs. I end with a broad brush characterization of a field of instructed SLA that is epistemologically diverse and ethically involved in justifying both the methodological rigor and the value commitments of our research programs and our studies. My goal is to open a space for disciplinary dialogue that allows us to engage in the articulation of valued research goals and professional and social responsibilities for the field of instructed SLA.
Enron/Andersen: Crisis in U.S. Accounting and Lessons for Government
Authors: Brown Richard E.
Published: August 2005

Accounting and auditing play a key role in the belief of ordinary taxpayers and investors in their institutions. This is equally true of the private and governmental sectors. The Enron/Andersen scandal, regrettably, is not an isolated case, but rather merely indicative of underlying, structural flaws in our financial systems. Moreover, there is evidence that some of these flaws may be present in governmental accounting and auditing. The Sarbanes‐Oxley Act of 2002 is an attempt to address these problems in the private sector, but does not address concerns in the public sector. Public sector accounting issues that need to be addressed and monitored include substandard audit work and related liability issues, the appropriate funding of GASB so as to ensure its independence, auditor fees, and auditor independence questions including protection of elected and appointed state auditors.
The Role of Philanthropy in Local Government Finance
Authors: Irvin Renée A. , Carr Patrick
Published: August 2005

Nonprofit organizations thrive on the altruism of citizens, and actively court donors for major gifts. Yet individual gifts to government agencies are often unexpected, sporadic, and initiated by the donor. This article introduces the phenomenon of private giving to local governments and tests hypotheses regarding the expected forms of giving to public agencies. Results indicate that philanthropy is and will likely remain a minor and highly variable source of revenue, making it an ill‐suited replacement for broad‐based tax revenue. However, deliberate government efforts to provide a suitable environment for private donations appear to succeed in attracting more gifts per capita.
RhoGDIs Revisited: Novel Roles in Rho Regulation
Authors: Dransart Estelle , Olofsson Birgitta , Cherfils Jacqueline
Published: August 2005

Small GTP‐binding proteins of the Rho/Rac/Cdc42 family combine their GDP/GTP cycle, regulated by guanine nucleotide‐exchange factors and GTPase‐activating proteins, to a cytosol/membrane cycle, regulated by guanine nucleotide dissociation inhibitors (rhoGDIs). RhoGDIs are endowed with dual functions in the cytosol where they form soluble complexes with geranylgeranylated GDP‐bound Rho proteins and at membrane interfaces where they monitor the delivery and extraction of Rho proteins to/from their site of action. They have little diversity compared with other Rho protein regulators and therefore have been regarded mostly as housekeeping regulators that distribute Rho proteins equally to any membranes. Recently, acquired data show that rhoGDIs, by interacting with candidate receptors/displacement factors or by phosphorylation, may in fact have active contributions to targeting Rho proteins to specific subcellular membranes and signaling pathways. In addition, the GDP/GTP and membrane/cytosol cycles can be uncoupled in certain cases, with Rho proteins either escaping the membrane/cytosol cycle or being regulated by rhoGDIs in their GTP‐bound form. Here, we survey recent structure‐function relationships and cellular studies on rhoGDIs and revisit their classical housekeeping role into novel and more specific functions. We also review their involvement in diseases.
Unifying Nomenclature for the Isoforms of the Lysosomal Membrane Protein LAMP‐2
Authors: Eskelinen Eeva‐Liisa , Cuervo Ana Maria , Taylor Matthew R.G. , Nishino Ichizo , Blum Janice S. , Dice J. Fred , Sandoval Ignacio V. , Lippincott‐Schwartz Jennifer , August J. Thomas , Saftig Paul
Published: August 2005

The present nomenclature of the splice variants of the lysosome‐associated membrane protein type 2 (LAMP‐2) is confusing. The LAMP‐2a isoform is uniformly named in human, chicken, and mouse, but the LAMP‐2b and LAMP‐2c isoforms are switched in human as compared with mouse and chicken. We propose to change the nomenclature of the chicken and mouse b and c isoforms to agree with that currently used for the human isoforms. To avoid confusion in the literature, we further propose to adopt the use of capital letters for the updated nomenclature of all the isoforms in all three species: LAMP‐2A, LAMP‐2B, and LAMP‐2C.
Measurements of K x-ray fluorescence parameters
Authors: Bennal A. S. , Shidling P. D. , Badiger N. M. , Thontadarya S. R. , Hanumaiah B.
Published: August 2005

A simple x-ray fluorescence experiment suitable for graduate and undergraduate laboratories is described. The experiment uses a NaI(Tl) x-ray spectrometer, a weak Co57 radioactive source (∼105 Bq), and medium-Z targets of silver, cadmium, indium, and tin. The K x-ray fluorescence yield, ωk, and K x-ray production cross section, σk, are measured for these targets. Accurate results are achieved by adopting a 2π detection geometry and by optimizing target dimensions for this experimental configuration. The experiment can be completed in 4 h and is suitable for student laboratories.
Calculation of x-ray wave fields in perfect crystals by applying Riemann’s method to solve the Takagi-Taupin equations
Authors: Palmisano C. , Zosi G.
Published: August 2005

The Takagi-Taupin equations are a set of partial differential equations that are fundamental in the dynamical theory of x-ray diffraction. We show how they can be manipulated to make them suitable for the application of Riemann’s method and present in detail the steps leading to their solution. To help readers gain insight into coherent x-ray wave fields, we calculate the intensity distribution of x-ray beams from mono- and polylithic perfect silicon single crystals. As an example of the interplay between wave fields, we illustrate the Pendellösung effect. We did some of the algebraic manipulations and most of the numerical calculations by using Mathematica.
The “Cheerios effect”
Authors: Vella Dominic , Mahadevan L.
Published: August 2005

Objects that float at the interface between a liquid and a gas interact because of interfacial deformation and the effect of gravity. We highlight the crucial role of buoyancy in this interaction, which, for small particles, prevails over the capillary suction that often is assumed to be the dominant effect. We emphasize this point using a simple classroom demonstration, and then derive the physical conditions leading to mutual attraction or repulsion. We also quantify the force of interaction in particular instances and present a simple dynamical model of this interaction. The results obtained from this model are validated by comparison to experimental results for the mutual attraction of two identical spherical particles. We consider some of the applications of the effect that can be found in nature and the laboratory.
Units and Dimensions in Physics
Authors: Page C. H.
Published: August 2005

The equations of physics are often interpreted as purely numerical relations. Endowing the symbols with “dimensional” quality as well as magnitude leads to a simpler, yet rigorous, mathematical structure, and permits changing units by direct substitution. Analysis of the mathematical universe of discourse of physical equations shows also that the four-dimensional l, m, t, q system of units is actually simpler than a three-dimensional system.
Padé–Laplace analysis of signal averaged voltage decays obtained from a simple circuit
Authors: Hellen Edward H.
Published: August 2005

The Padé–Laplace method is an interesting yet relatively unknown method for determining the exponential time constants in a decaying signal. We apply it to data from a simple electronic circuit specifically designed for investigations of signal averaging. Possible decays of the voltage include single, multi-exponential, and predominantly logarithmic. Students in our computer-interfacing course write a LABVIEW program that collects the data and performs the signal averaging.
Hamilton’s principle: Why is the integrated difference of the kinetic and potential energy minimized?
Authors: Rojo Alberto G.
Published: August 2005

Why is the integrated difference of the kinetic and potential energies the quantity to be minimized in Hamilton’s principle? I use simple arguments to convert the problem of finding the path of a particle connecting two points to that of finding the minimum potential energy of a string. The mapping implies that the configuration of a nonstretchable string of variable tension corresponds to the spatial path dictated by the principle of least action; that of a stretchable string in space–time is the one dictated by Hamilton’s principle. This correspondence provides the answer to the question.
Enrollments and Degrees Awarded to Physics Majors
Authors: White Marsh W.
Published: August 2005

Data are presented showing the enrollments of undergraduate and graduate students in physics in approximately 500 colleges and universities in the United States. In the academic year 1949–50, 12,670 undergraduate and 5,560 graduate physics majors were enrolled. These numbers are about twice those of four years previous. During 1948–49 the number of degrees in physics granted were: bachelors, 3,495; masters, 920; doctors, 274. For 1949–50 the number of degrees to be granted was estimated as: bachelors, 4050; masters, 1,000; doctors, 340. The production of doctorates in physics has now reached a “normal” output, based on previous trends which indicated a rapid increase. A tabulation is presented of the bachelors, masters, and doctors degrees granted in 1948–49 by each of the 500 colleges and universities in the United States.
On the Representation of the Static Polarization of Rigid Dielectrics by Equivalent Charge Distributions
Authors: Fisher L. H.
Published: August 2005

The representation of statically polarized rigid dielectrics (homogeneous isotropic, homogeneous anisotropic, nonhomogeneous isotropic) by equivalent induced surface and volume charge distributions is examined in detail. Attempts at interpretation of equivalent surface charge densities in crystals (isotropic and nonisotropic) and of equivalent volume charge densities in crystals (nonisotropic) indicate that, for these cases, the concepts are artificial and are of limited physical significance. Difficulties in interpretation do not arise for gases, liquids, amorphous solids, or solids made up of large numbers of randomly oriented crystals. The corresponding magnetostatic problems are discussed, although interpretation is not attempted in view of the artificiality of the concept of the magnetic pole.
Experiments with Doubly Refracting Crystals
Authors: Jeppesen Myron A.
Published: August 2005

The birefringence of mica and of quartz is measured by an interference method which is very accurate for thin sections. The orientation and identification of the axes of mica are determined by observation of the specimen in convergent polarized light. These experiments are suitable for the advanced undergraduate laboratory.
The Solution of Differential Equations by Electrical Analog Computers
Authors: Ryerson Joseph L.
Published: August 2005

Electrical systems for solving total differential equations are classified as high speed or low speed with citations of existing commercial equipment. A symbolism is proposed for the physical components which perform the mathematical operations without elaborating upon the technical details of their design.

The solutions of simultaneous linear algebraic equations, simultaneous differential equations, and differential equations with variable coefficients are discussed and illustrated. The article contains fourteen illustrations of symbols and system wiring schemes.
Specialized Physics
Authors: Dwight C. Harrison
Published: August 2005

Physics courses offered in American universities may be classified as either “Standard” or “Specialized.” The former stress all parts of physics more or less equally, and laboratory work accompanies the lectures. The need for the specialized type of course is apparent to students in fields where a knowledge of the subject is very important in their training but where they do not need, and usually do not have time for, all of the topics covered in the standard course. Such students are those in Architecture, Business Administration, Music, Applied Arts, and so forth. The author briefly analyzes the two types of courses, emphasizing the advantages of each, and calls attention to the fact that both types of courses are offered at the University of Cincinnati.
The Well-Informed Heat Engine
Authors: Raymond Richard C.
Published: August 2005

The failure of a heat engine to defeat the second law of thermodynamics by using density fluctuations to convert heat to work without leaving other changes in the universe is usually explained by saying that the fluctuations of the engine itself would defeat such an operation or that the microscopic nature of the fluctuations prevents their being put to a macroscopic use. It is shown here that with a proper definition of stored information, a heat engine can be made to convert heat to work without other changes in its immediate system, provided that an outside observer creates in the system a negative information entropy equal to the negative entropy change involved in the operation of the engine. This equivalence of a communication entropy change to a thermodynamic entropy change leads to the definition of the entropy of a nonequilibrium system as the algebraic sum of the thermodynamic entropy which the system would have at equilibrium and the information entropy necessary to construct the specified state from the equilibrium state.
A Laboratory Experiment on the Determination of γ for Gases by Self-Sustained Oscillations
Authors: Koehler W. F.
Published: August 2005

The apparatus used is a Rüchardt Apparatus with a small hole bored through the wall of the tube which permits gas to escape when the ball is above the hole. The ball is caused to oscillate symmetrically with respect to the hole by adjusting an inlet valve. When adjusted, the constant rate of inflow of gas is equal to the average rate of escape of gas. The resulting fluctuation of the pressure is sinusoidal to a high degree of approximation and maintains the oscillations of the ball indefinitely. An elementary theory predicts that γ can be determined from the measurement of the period of oscillation, mean pressure, mass of the ball, diameter of the ball, and volume of the container. Results for most of the common gases are reproducible to within 0.2 percent and differ from the accepted values by 1 percent.
Some Experiments in Viscous Fluid Flow
Authors: Riess Karlem , Baudean John E.
Published: August 2005

The motion of a viscous fluid contained between two coaxial cylinders is described. A speed criterion, although derived assuming the cylinders to have infinite length, is confirmed for the case of cylinders of finite length.

It is found that in the apparatus used there are three modes of viscous fluid motion: (a) All moving particles move in circles concentric with the axis. (b) The fluid within the annulus between the two cylinders divides itself into pairs of vortex rings in which the particles of the fluid rotate simultaneously both about the axis of the cylinders and the core of the vortex. (c) Turbulent motion appears.

The optical property of visibility of planes of equal shear in the liquid under steady flow is used to study glycerine-water and castor oil-ethyl alcohol solutions, as well as several pure oils. An explanation of the visibility of these lines is proposed. An adaptation to the measurement of viscosities is suggested.
On Newton's Law of Attractions
Authors: Hussain Zahur
Published: August 2005

A careful analysis of the demonstration of his fundamental law of attractions, set forth by Newton in Proposition LXIX of Book I of the Principia, seems to show that the objective of the proof is not to be attained without first assuming the very points which are there sought to be established. As soon as we proceed on the basis of such assumptions, the subject puts on a different appearance, which is deeply helpful in appreciating afresh the connection between a gravitational and inertial measure of masses. There is brief secondary treatment of the so-called tautologous character of Newton's definition of material density and of a field concept implied in newtonian description of accelerative forces.
Introduction to Polarization of Electromagnetic Waves
Authors: Andrews C. L.
Published: August 2005

If microwaves are employed in the first demonstration of polarization of electromagnetic waves, then one does not need to rely upon analogy or theory to give the direction of polarization. The electric field is parallel to the antenna. Simple means are described for using a hand-sized triode transmitter and a hand-sized intensity meter in the class room demonstration and laboratory study of polarization by a parallel wire screen, polarization by reflection from dielectrics, elliptical polarization, and rotation of the plane of polarization.
Engineering Physics at Cornell
Authors: Smith Lloyd P.
Published: August 2005

The establishment, administration, and conduct of a new program of technical training to prepare students for industrial research and advanced engineering development at Cornell University is described.
The Teaching of Physics
Authors: Swann W. F. G.
Published: August 2005

Observations upon the teaching of physics, with special reference, in the case of courses intended for cultural purposes, to the importance of emphasis on ideas rather than facts, except insofar as they are necessary to illustrate the ideas.
About an Argument of Newton
Authors: Hussain Zahur
Published: August 2005

The view is first developed that it was in the effort of Copernicus' successors to justify fundamentally the validity of the change of conception usually associated with his name that the science of dynamics took a systematic shape. Then Newton's argument is examined that the ptolemaic alternative must mean a disruption of the solar system which is not witnessed and, therefore, the Copernicus-Kepler scheme ought to be accepted absolutely. This particular reasoning of Newton is shown, however, to suffer from a defect. The basis of others of Newton's arguments on the subject is considered, and it is presented that the application of dynamical principles makes the copernican standpoint on planetary motions no more final than the high degree of probability adduced in its favor by Copernicus himself on the ground of its merit of simplicity and harmony as compared with Ptolemy's picture.
A Laboratory Course in Electronics
Authors: Schultz H. L. , Wadey W. G.
Published: August 2005

An electronics laboratory course developed primarily for junior and senior students in physics is described. Emphasis is placed on the theory of operation of vacuum tubes and their uses as circuit elements in research applications. The equipment, largely home-constructed and described in some detail, is provided in a form which allows quick assembly by the student, and individual components are designed to provide maximum flexibility in setups.
Some Behavior Objectives for Laboratory Instruction
Authors: Kruglak Haym
Published: August 2005

A sample outline of objectives illustrates a method of laboratory instruction in elementary electricity in terms of student behavior. The twenty-six specific objectives are grouped under five categories: instrumental skills, skills in the use of the controlled experiment, problem solving skills, miscellaneous skills, functional understanding of principles and habits.
On Illustrating the Regularity of Alpha-Radioactivity
Authors: Van Name F. W.
Published: August 2005

The regularity of alpha-radioactivity is usually illustrated by the Geiger-Nuttall Law. Guided by the quantum-mechanical solution of the problem of alpha-particle emission, a way of plotting these data is shown, which yields a more satisfactory straight line than the Geiger-Nuttall plot.
Dispersion and Resolving Power of Prism Spectrometers
Authors: Hazzard George W.
Published: August 2005

Brief derivations of dispersion and resolving power give their expression in terms of the directly measurable angle of the prism and its angle of deviation at different wavelengths. Elimination of the length of the prism base seems to improve student understanding of the quantities. Students' experimental results are given to show the precision to be expected.
Potential against Resistance—a Graphical Review
Authors: Sleator W. W.
Published: August 2005

In this paper the graph of potential against resistance, often used to picture the discharge of an electric cell, is shown to represent the transformations of energy involved in the process. With this property in view, the V-R diagram becomes applicable to every energy transformation that can occur in an electric circuit. Such a diagram is used accordingly to represent the charging of a storage cell as well as its discharge, the charging of a condenser, the operation of the dc generator and motor, the performance of the copper-iron thermocouple, and the increase and decrease of current in an inductive coil without iron. It is hoped that this unified treatment of important electric processes may reveal their essential similarities and make them better understood and more easily remembered.