bluuebunny/crossref_metadata_2025 huggingface dataset:
Surgical Training and Simulation Laboratory at Baystate Medical Center
Authors: Earle David
Published: June 2007

The work hour restrictions imposed by the surgical residency review committee, without a curriculum change, essentially reduces training programs by 30%. The logical result of this is the risk that a higher percentage of surgeons beginning independent practice will fall below the competence level. We believe that simulation will play a vital role in the curriculum to enhance the clinical environment and make the learning environment better and more efficient. Baystate Medical Center (Springfield, Mass) is an affiliate of Tufts University School of Medicine and provides tertiary medical care for the western portion of the state. Our surgical residency program has developed and maintained a simulation center specifically to augment training of surgical knowledge and manual skills. We are also actively involved in education research and curriculum design locally and on a national level. Our center is rapidly becoming a multidisciplinary environment incorporating other residency and clinical programs within the health system and beyond. We are actively pursuing the development of novel assessment technology that will not only integrate the simulation center with the clinical arena but also link educational and clinical outcomes. This will allow us to automatically tailor the educational environment to the individual needs of the learner as they change over time, as well as look at quality improvement related to our educational and research endeavors.
Buschke-Lowenstein Tumor Successful Treatment by Surgical Excision Alone: A Case Report
Authors: Renzi Adolfo , Giordano Pasquale , Renzi Guiseppe , Landolfi Vincenzo , del Genio Alberto , Weiss Eric G.
Published: June 2007

Perianal giant condyloma acuminatum is a rare variant of condyloma acuminata and often represents a therapeutic challenge. We report a case successfully treated with surgical excision alone.
Life Expectancy Benefits of Gastric Bypass Surgery
Authors: Pope G. Darby , Finlayson Samuel R.G. , Kemp Jason A. , Birkmeyer John D.
Published: June 2007

Bariatric surgery is the most effective treatment for achieving sustained weight loss in morbidly obese patients. Although the use of gastric bypass is growing rapidly, the potential life expectancy benefits of the procedure are unknown. We created a Markov decision analysis model to examine the effect of gastric bypass surgery on life expectancy in morbidly obese patients (body mass index [BMI] = 40 kg/m2). Input assumptions for the model were obtained from published life tables (baseline mortality risks), epidemiologic studies (obesity-related excess mortality), and large case series (surgical outcomes). In our baseline analysis, a 40-year-old woman (BMI = 40 kg/m2) would gain 2.6 years of life expectancy by undergoing gastric bypass (38.7 years versus 36.2 years without surgery). In sensitivity analysis, life-years gained with surgery remained substantial when assumptions were varied across reasonable ranges for surgical mortality risk (1.0-3.0 years) and effectiveness (0.9-4.4 years). Life-years gained with gastric bypass surgery did not vary considerably by age and sex subgroups. Relative to other major surgical procedures, gastric bypass for morbid obesity is associated with substantial gains in life expectancy. Long- term data from prospective studies are needed to confirm this finding.
How Are Decisions to Introduce New Surgical Technologies Made? Advanced Laparoscopic Surgery at a Canadian Community Hospital: A Qualitative Case Study and Evaluation
Authors: Sharma Bharat , Danjoux Nathalie M. , Harnish Julie L. , Urbach David R.
Published: June 2007

The introduction of many new surgical technologies is associated with increased costs and uncertainty regarding risks and benefits. Currently, little is known about how decisions are made regarding the adoption of surgical innovations. To study the decision-making process for adoption of advanced laparoscopic surgical procedures at a community hospital in Toronto, Canada, we used qualitative case study methods. Data were collected using semi-structured interviews with key informants. We performed a modified thematic analysis of the data, using the conceptual framework for priority setting known as accountability for reasonableness, which consists of 4 conditions: relevance, publicity, appeals, and enforcement. Several advanced laparoscopic surgical procedures were introduced at the hospital between 2000 and 2005. During that time, there was no structured, explicit process for making decisions about introducing new surgical technologies. Use of the new surgical technologies was relevant, as measured by the perception of patient benefit and alignment with the hospital’s strategic priorities. There was no systematic structure in place to oversee publicity, appeals, or enforcement. The decision to adopt advanced laparoscopic surgery at a community hospital in Toronto, Canada, was made primarily on the basis of its relevance to patient care. The process for making decisions about the adoption of new surgical technologies can be improved.
A Novel Stentless Mitral Valve
Authors: Keeling W. Brent , Maxey Thomas S. , Sayad Dany , Martini Nick , Blazick Elizabeth , Sommers K. Eric
Published: June 2007

Stentless mitral valves have found little clinical utility to date due to difficulty in insertion. A new design for a stentless mitral valve, a modification of an existing aortic stentless prosthesis, is described. The new design mimics the native mitral physiology, and its insertion is easier than with existing stentless mitral valves. Commercially available stentless aortic valves were inserted into 2 pigs. The valves were modified so that the commissural posts were restrained. The valves were partially recessed into the left ventricular cavity, secured to the annulus, and anchored to the native papillary muscles. Both pigs were weaned from bypass successfully, and both valves functioned normally with trace regurgitation noted on echocardiography. This design affords the benefit of the reapproximation of native physiology. Preservation of papillary-annular continuity should allow maximal left ventricular function. Lack of a stent should allow avoidance of long-term anticoagulation.
Video Technology to Advance Safety in the Operating Room and Perioperative Environment
Authors: Yan Xiao  , Schimpff Stephen , Mackenzie Colin , Merrell Ronald , Entin Eileen , Voigt Roger , Jarrell Bruce
Published: June 2007

Video is a powerful medium and is underused for patient safety in several areas: education, real-time consultation, process improvement, research, and workflow coordination. We illustrate this point through an overview of uses of video in health care by the authors and others in several institutions. These uses were in the context of team work training, operating room coordination, technical skills of invasive procedures, process improvement, telementoring, and multimedia video records. Also described are several key issues associated with the use of video, such as ethics and legal concerns. Technology advances and new methods will make video an important tool for improving patient safety.
Engaging Patients in Cardiovascular Disease Risk Reduction: From Empathy to Erectile Dysfunction
Authors: Miner Martin
Published: June 2007

Six of the major risk factors for coronary heart disease involve lifestyle practices, often not discerned in primary care. Differing paradigms for preventive care and modification for risk are thereby addressed. Motivational interviewing is one technique of reflective listening and nonjudgmental concern to engage patients in behavioral change. As an example of the rationale for intervention to reduce the risk of coronary artery disease, the Commonwealth Study of 2000 is highlighted, noting the failure of men to address warning signals of cardiovascular disease risk and the relationship of erectile dysfunction in men as a possible sentinel marker for early detection of coronary artery disease. A recent article in Journal of the American Medical Association addressed the relationship of incident erectile dysfunction and presence of cardiovascular disease over an 11-year period in more than 4000 men. Therefore, the penis may be an appropriate barometer to determine cardiovascular health and risk and allow partnering with a clinician to modify risk because it is easily identifiable. This is an example of gender-based risk stratification and education that will be addressed in a series of articles on cardiovascular disease risk.
The Unity of Rawls’s Work
Authors: Wenar Leif
Published: June 2007

This article presents a unifying interpretation of Rawls’s major works. The interpretation emphasizes the parallels in Rawls’s theories of justice and legitimacy for domestic and global institutions.
Medicaid programme changes and the chronically ill: early results from a prospective cohort study of the Oregon Health Plan
Authors: Solotaroff Rachel , Devoe Jennifer , Wright Bill J. , Smith Jeanene , Boone Janne , Edlund Tina , Carlson Matthew J.
Published: June 2007

Objective: To describe the impacts of recent Oregon Health Plan (OHP) policy changes on individuals living with chronic illness in Oregon.

Methods: A mail survey was conducted of 1374 OHP beneficiaries who were directly affected by the new policies. The analyses reported in this article represent baseline findings from the first of three survey waves in an ongoing prospective cohort study.

Results: A significant association was found between Medicaid policy changes and high rates of disenrolment from the OHP. Compared to the non-chronically ill, the chronically ill were more likely to report inability to pay for medications, higher medical debt, more unmet health needs, and poorer health status. Among the chronically ill, those who lost insurance reported decreased access to and utilization of healthcare, more medical debt, and more restriction of medications.

Discussion: As policy-makers restructure public programmes to accommodate tight budgets and rising healthcare costs, people with chronic illness can easily be overlooked. Chronically ill individuals face disproportionate financial and health burdens. Small cost-saving policy changes can lead to widespread disenrolment that cascades into reduced access to healthcare services, altered utilization patterns, and financial strain.
`What is expressed is not always what is felt': coping with stigma and the embodiment of perceived illegitimacy of multiple sclerosis
Authors: Grytten Nina , Måseide Per
Published: June 2007

Objective: In this study, we investigated the stigma experienced by people with multiple sclerosis (MS) and their relatives. We describe coping as impression management of the body to counteract stigma and illegitimacy.

Methods: Fourteen people, including those with MS in the middle and later stages of illness, and their relatives were informally interviewed. The interviews were tape-recorded, subsequently yielding a 500-page document.

Results: The findings point to the embodied perception of illegitimacy as a dimension of stigma. Informants reported instrumental and affective advantages of purposefully concealing or informing about their MS to influence social judgement in interpersonal encounters.

Discussion: MS sufferers apply a tactic of protective disclosure by which they seek to guard their sense of self. The strategy of preventive disclosure is employed to obtain assistance from others. Furthermore, the strategy of concealing MS is conducted purposefully to prevent the sufferer being deprived of social belonging, especially with regard to work.
Selection of patients for inpatient rehabilitation or direct home discharge following total joint replacement surgery: a comparison of health status and out-of-pocket expenditure of patients undergoing hip and knee arthroplasty for osteoarthritis
Authors: Tribe Kate L. , Lapsley Helen M. , Cross Marita J. , Courtenay Brett G. , Brooks Peter M. , March Lyn M.
Published: June 2007

Objectives: To analyse the differences in patient health outcomes and out-of-pocket costs following hip and knee joint replacement for osteoarthritis between patients who went home immediately after the acute care hospital stay and those who were admitted to inpatient rehabilitation care before going home.

Methods: One hundred and eighteen patients undergoing total hip or knee replacement in Sydney, Australia completed cost diaries, SF-36 and WOMAC Index, pre-operatively and for one year post-operatively.

Results: The health status of all groups improved significantly from before surgery to 12 months post-surgery. No significant difference in health status at 12 months post-surgery was seen between home and rehabilitation patients for either hip or knee replacement. Both hip replacement home and rehabilitation patients and knee replacement home patients reported lower out-of-pocket expenditure from before surgery to 1 year post-surgery.

Discussion: The majority of total joint replacement patients can be discharged directly home and achieve excellent outcomes at 12 months post-surgery. We would recommend more focused randomized studies to explore the most suitable patient selection for rehabilitation.
Cost-effectiveness analyses and modelling the lifetime costs and benefits of health-behaviour interventions
Authors: Graves Nicholas , Mckinnon Loretta , Reeves Marina , Scuffham Paul , Gordon Louisa , Eakin Elizabeth
Published: June 2007

Background: We describe an approach to estimating the cost-effectiveness of an intervention that changes health behaviour. The method captures the lifetime costs and benefits incurred by participants in an ongoing cluster-randomized controlled trial of an intervention that aims to change health behaviour. The existing literature only captures short-term economic and health outcomes.

Methods: We develop a state-transition Markov model of how individuals move between different health behaviour states over time. We simulate hypothetical data to describe the costs and health benefits of the intervention, illustrate how the data collected in the ongoing randomized controlled trial can be used and demonstrate how incremental cost-effectiveness ratios are estimated.

Results: On the basis of the simulated (i.e. hypothetical) data, we estimate the cost per quality-adjusted life year. The estimate reflects the lifetime health and economic consequences of the intervention.

Discussion: The method used for the cost-effectiveness analysis described in this paper is appropriate for investigating whether interventions that change health behaviour in relation to chronic diseases represent good value for money as compared to alternative uses of scarce healthcare resources.
Factors important for the measurement of social comparison in chronic illness: a mixed-methods study
Authors: Dibb Bridget , Yardley Lucy
Published: June 2007

Objectives: The aim of this study was to examine social comparison in illness using a mixed-methods approach that combined inductive exploration of how people used social comparison in this self-help group with a quantitative study of social comparison processes and their relationship to quality of life.

Methods: The qualitative study involved 15 semi-structured interviews with people with Ménière's disease. Themes from the analysis of the interviews informed the development of the Social Comparison in Illness Scale (SCIS), which was then validated in a questionnaire study, in which participants with Ménière's disease ( n=196) completed the SCIS, the previously validated Identification/Contrast social comparison scale, and the SF-36 health status questionnaire.

Results: The qualitative study uncovered a wide range of forms of social comparison, including upward, downward and lateral comparison on illness and coping dimensions, as well as comparing solely for informational purposes. The quantitative study indicated that these varied directions and dimensions of social comparison could be mapped onto five reliable categories that were related to quality of life: upward positive and downward positive comparison, upward negative and downward negative comparison, and comparing for information.

Discussion: These analyses highlight the complexity of socially comparing in chronic illness, but also confirm the validity of the Identification/Contrast model of social comparison in this context.
Ultrasound Contrast Agents
Authors: Robinette William B.
Published: June 2007

The introduction of ultrasound contrast agents will bring new applications of this diagnostic imaging technology into clinical practice. Vascular, organ-specific, and oral agents are now in clinical trials and will soon be available. The development and properties of ultrasound contrast agents, most of which are based on gas-filled microbubbles, are reviewed. The first group of agents designed to overcome the limitations of free gas bubbles were of more uniform size but were either too large to cross the pulmonary capillary bed or lasted for only a short time in the circulation. The next group was able to produce enhancement over a period of minutes, but did not enhance the parenchyma of organs. The most recently developed intravenous agents exhibit parenchymal enhancement or are tissue-specific during B-mode imaging. Oral contrast agents may be used to reduce the artifacts created by gas in the gastrointestinal tract and to more clearly image the upper abdomen. Specific agents within each of the groups are described. The use of harmonic imaging is reviewed.
Gene therapy as salvage
Authors: Kohn Donald B.
Published: June 2007

Chinen and colleagues describe the outcome of gene therapy for 3 young adolescents with XSCID for whom prior attempts at allogeneic bone marrow transplant had failed to achieve significant immunologic reconstitution. Clear-cut clinical benefits have recently been obtained in multiple trials of gene therapy using hematopoietic stem cells (HSCs) for infants with XSCID and adenosine deaminase (ADA)-deficient SCID, and for young adults with chronic granulomatous disease (CGD). Thus, the debate over gene therapy has moved from “will it ever be beneficial?” to “when is it beneficial?” Studies are moving forward exploring the use of gene-corrected autologous HSCs in treating other immune deficiencies (eg, Wiskott-Aldrich syndrome), hemoglobinopathies, leukodystrophies, and mucopolysaccharidoses, as well as multiple applications to oncological diseases.
Myelofibrosis with myeloid metaplasia: targeted therapy
Authors: Cairo Mitchell S.
Published: June 2007

In this issue of Blood, Wagner-Ballon and colleagues provide new insights into the pathogenesis of myelofibrosis with myeloid metaplasia (MMM) and a targeted therapeutic approach of NF-κB inhibition with the proteosome inhibitor bortezomib.
An early response regulatory cluster induced by low temperature and hydrogen peroxide in seedlings of chilling-tolerant japonica rice
Authors: Cheng Chen , Yun Kil-Young , Ressom Habtom W , Mohanty Bijayalaxmi , Bajic Vladimir B , Jia Yulin , Yun Song Joong , de los Reyes Benildo G
Published: June 2007

Background

Plants respond to low temperature through an intricately coordinated transcriptional network. TheCBF/DREB-regulated network of genes has been shown to play a prominent role in freeze-tolerance ofArabidopsisthrough the process of cold acclimation (CA). Recent evidence also showed that theCBF/DREBregulon is not unique to CA but evolutionarily conserved between chilling-insensitive (temperate) and chilling-sensitive (warm-season) plants. In this study, the wide contrast in chilling sensitivity between indica and japonica rice was used as model to identify other regulatory clusters by integrative analysis of promoter architecture (ab initio) and gene expression profiles.

Results

Transcriptome analysis in chilling tolerant japonica rice identified a subset of 121 'early response' genes that were upregulated during the initial 24 hours at 10°C. Among this group were four transcription factors includingROS-bZIP1and another larger sub-group with a common feature of having as1/ocs-like elements in their promoters. Cold-induction ofROS-bZIP1preceded the induction of as1/ocs-like element-containing genes and they were also induced by exogenous H2O2at ambient temperature. Coordinated expression patterns and similar promoter architectures among the 'early response' genes suggest that they belong to a potential regulon (ROS-bZIP – as1/ocsregulatory module) that responds to elevated levels of ROS during chilling stress. Cultivar-specific expression signatures of the candidate genes indicate a positive correlation between the activity of the putative regulon and genotypic variation in chilling tolerance.

Conclusion

A hypothetical model of an ROS-mediated regulon (ROS-bZIP – as1/ocs) triggered by chilling stress was assembled in rice. Based on the current results, it appears that this regulon is independent of ABA andCBF/DREB, and that its activation has an important contribution in configuring the rapid responses of rice seedlings to chilling stress.
Using a multi-method, user centred, prospective hazard analysis to assess care quality and patient safety in a care pathway
Authors: Dean Joanne E , Hutchinson Allen , Escoto Kamisha Hamilton , Lawson Rod
Published: June 2007

Background

Care pathways can be complex, often involving multiple care providers and as such are recognised as containing multiple opportunities for error. Prospective hazard analysis methods may be useful for evaluating care provided across primary and secondary care pathway boundaries. These methods take into account the views of users (staff and patients) when determining where potential hazards may lie. The aim of this study is to evaluate the feasibility of prospective hazard analysis methods when assessing quality and safety in care pathways that lie across primary and secondary care boundaries.

Methods

Development of a process map of the care pathway for patients entering into a Chronic Obstructive Pulmonary Disease (COPD) supported discharge programme. Triangulation of information from: care process mapping, semi-structured interviews with COPD patients, semi-structured interviews with COPD staff, two round modified Delphi study and review of prioritised quality and safety challenges by health care staff.

Results

Interview themes emerged under the headings of quality of care and patient safety. Quality and safety concerns were mostly raised in relation to communication, for example, communication with other hospital teams. The three highest ranked safety concerns from the modified Delphi review were: difficulties in accessing hospital records, information transfer to primary care and failure to communicate medication changes to primary care.

Conclusion

This study has demonstrated the feasibility of using mixed methods to review the quality and safety of care in a care pathway. By using multiple research methods it was possible to get a clear picture of service quality variations and also to demonstrate which points in the care pathway had real potential for patient safety incidents or system failures to occur. By using these methods to analyse one condition specific care pathway it was possible to uncover a number of hospital level problems. A number of safety challenges were systems related; these were therefore difficult to improve at care team level. Study results were used by National Health Service (NHS) stakeholders to implement solutions to problems identified in the review.
Immunohistochemical expression of SMAD4, CK19, and CA19-9 in fine needle aspiration samples of pancreatic adenocarcinoma: Utility and potential role
Authors: Zapata Mauricio , Cohen Cynthia , Siddiqui Momin T
Published: June 2007

Background

Pancreatic adenocarcinoma comprises 85% of all cases of pancreatic malignancies. From a diagnostic standpoint, these tumors are readily diagnosed by fine needle aspiration, with an accuracy of greater than 90%; however it is often difficult to ascertain whether these are primary or metastatic in nature. This study was undertaken to see the usefulness of CK19, CA19-9 and a newly described marker, SMAD4 in confirming the pancreatic origin of these tumors. Briefly, SMAD4 (DPC4) is a tumor-suppressor gene located on chromosome 18q which has been shown to mediate the downstream effects of TGF-β superfamily signaling, resulting in growth inhibition. The loss of SMAD4, which as been reported to occur in 55% of pancreatic ductal adenocarcinomas may lead to up regulation of cell cycle proteins and hence increase cellular proliferation. In addition, SMAD4 has been suggested to possibly have prognostic potential, with the presence of SMAD4, indicating shorter survival after resection.

Design

Clinical data was reviewed to identify patients with proven, primary pancreatic adenocarcinoma. A total of 25 patients with diagnostic material from fine needle aspiration cell blocks, were retrieved from our files at Emory University Hospital. In addition cell blocks from clinically diagnosed non-pancreatic adenocarcinomas were also selected as controls for this study (10 cases of colonic adenocarcinoma, 10 cases of pulmonary adenocarcinoma, 10 cases of breast ductal carcinoma and 10 cases of ovarian mucinous adenocarcinoma). Formalin fixed, paraffin-embedded sections from these were stained with SMAD4, CK19, and CA19-9, using pressure cooker antigen retrieval, labeled polymer HRP (DAKO), and the DAKO autostainer.

Results

Immunohistochemical staining was reviewed based on intensity (negative, low-positive, and high-positive) and percentage of cells. In primary pancreatic ductal adenocarcinoma, CK 19 showed diffuse cytoplasmic positivity in 23 of 25 cases, CA 19-9 showed apical cytoplasmic staining in all 25 cases, and SMAD4 showed nuclear staining in 20 of 25 cases. In the control group comprising of non-pancreatic adenocarcinoma SMAD4 was negative (100%) in all 10 cases of colonic and pulmonary adenocarcinoma. However 1 of 10 cases (10%) of breast and ovarian adenocarcinoma did show low positivity nuclear staining. However the expression of CA19-9 and CK19 was more variable in these different non-pancreatic malignancies.

Conclusion

Pancreatic adenocarcinoma showed positive immunohistochemical staining for SMAD4 in 80%, CK19 in 100% and CA19-9 in 100% of the selected cases. These markers, when used as a panel, may confirm the diagnosis of pancreatic adenocarcinoma in fine needle aspiration samples, and help in differentiating from metastatic adenocarcinoma. This may help in determination of appropriate surgical and chemotherapeutic options.
Selection of an improved RNA polymerase ribozyme with superior extension and fidelity
Authors: Zaher Hani S. , Unrau Peter J.
Published: June 2007

Our current understanding of biology suggests that early life relied predominantly on RNA for catalysis and replication. Here, we report the isolation of an RNA polymerase ribozyme called B6.61 that exhibits superior extension and fidelity relative to its progenitor, the Round-18 polymerase. The B6.61 polymerase was selected from a mutagenized pool containing ∼ 9 × 1014 sequence variants through the use of a novel large-scale in vitro compartmentalization system. B6.61 polymerized all tested primer–template (PT) complexes faster than the Round-18 variant. For one PT, B6.61 exhibited dramatically faster elongation past one full helical turn and incorporated at least 20 nucleotides of sequence, setting a new extension record for an RNA polymerase ribozyme. The increased efficiency of the B6.61 construct was related to improvements in fidelity, with the new variant incorporating less incorrect wobble base pairs than its parent. This new polymerase demonstrates the feasibility of evolving an artificial RNA replicase ribozyme in the foreseeable future.
Procedural justice in punishment systems: Inconsistent punishment procedures have detrimental effects on cooperation
Authors: van Prooijen Jan‐Willem , Gallucci Marcello , Toeset Gaby
Published: June 2007

The current research examines a moderator who predicts in what situations punishment can have detrimental effects on cooperation. We hypothesized that when a punishment system is perceived as procedurally unfair, people's cooperation level decreases. Results of two experiments indicated that participants cooperated less in a group‐based trust game when punishment was inconsistent between persons (i.e. not all group members would be punished for defection) than when punishment was consistent between persons (i.e. any group member who defected would be punished) or when there was no punishment. These effects were mediated by perceived belongingness. The authors conclude that an unfair punishment system leads people to feel marginalized as a group member, and this prompts them to display less cooperation.
Pilot Study for the Standardization of Insulin Immunoassays with Isotope Dilution–Liquid Chromatography/Tandem Mass Spectrometry
Authors: Rodríguez-Cabaleiro Diego , Van Uytfanghe Katleen , Stove Veronique , Fiers Tom , Thienpont Linda M
Published: June 2007

Background: An international working group convened by the American Diabetes Association (ADA) called for a reference measurement procedure for use in a trueness-based standardization project of insulin immunoassays. In view of this demand, we conducted a pilot study to investigate the feasibility of such a standardization project with our isotope dilution-liquid chromatography/tandem mass spectrometry (ID-LC/tandem MS) procedure.

Methods: We evaluated the precision, accuracy, and limit of quantification (LoQ) of the ID-LC/tandem MS procedure by use of insulin-free serum supplemented with insulin to give 3 pools with concentrations of 0.0796, 0.769, and 5.56 μg/L. We conducted a pilot method comparison study with 4 immunoassays and 80 samples from fasting and glucose-stimulated patients.

Results: The within-run and total imprecision (CV) ranged from 3.2% to 6.3% and from 4.9% to 12.1% (listing sequence from the high to the low pool). The recovery from supplemented insulin-free sera ranged from 101.8% to 104.1%, and the LoQ was 0.07 μg/L (12 pmol/L). Weighted Deming regression and correlation analysis of the method-comparison data showed considerable between-assay variation for the immunoassays but, with the exception of one assay, excellent correlation with ID-LC/tandem MS. Recalibration of the immunoassay results considerably reduced the between-assay variation. Moreover, after recalibration, 3 of the 4 assays fulfilled the total error specification of 32% proposed by the ADA Workgroup.

Conclusions: Recalibration of insulin assays by regression equations established from method comparison with ID-LC/tandem MS can result in successful standardization and fulfillment of the total error criterion proposed by the ADA Workgroup.
How can we make laboratory testing safer?
Authors: Boone D. Joe
Published: June 2007

Clin Chem Lab Med 2007;45:708–11.
Műtrágyázás és meszezés hatása a 30 éves kompolti OMTK kísérletben
Authors: Kádár Imre , Holló Sándor
Published: June 2007

Az Országos Egységes Műtrágyázási Tartamkísérletekhez (OMTK)
tartozó B-1730 sz. kisparcellás kísérlet Kompolton beállított változatát
vizsgáltuk 1997-ben, a kísérlet 30. évében. A csernozjom barna erdőtalaj
szántott rétege meszet nem tartalmaz, erősen kilúgzott, a pH(KCl) eredetileg 5
körüli, a hidrolitos aciditás 15-25 közötti, agyagtartalma 40-48 %,
humusztartalma 2,5-3,0%, nitrogénnel közepesen, foszforral gyengén, míg
káliummal kielégítően ellátott. A talajvíz 8-10 m mélyen helyezkedik el, a
termőhely aszályérzékeny. A főbb eredmények: - A kísérlet 30. évében a 8 t/ha
őrölt mészkőporral végzett meszezés utóhatása nyomon követhető, meszezett
talajon a pH(KCl) és a pH(H
2
O) egyaránt 0,6 egységgel nagyobb, az y
1
pedig
29-ről 20-ra csökkent. - A talajok cc. HNO
3
+ cc. H
2
O
2
feltárással
becsült „összes”-P készlete 500 mg/kg mennyiségről 780 mg/kg-ra nőtt a
maximális P-adaggal, mely 64%-os gazdagodást jelent a szántott rétegben. Ezzel
együtt az „összes”-Sr készlet mintegy 50%-kal emelkedett a szuperfoszfátok 2%
Sr-szennyezéséből eredően. A kontrolltalajban átlagosan 0,45%, a meszezetten
0,50% Ca-tartalmat mértünk. A különbség statisztikailag igazolható volt.
K-trágyázással a K-készlet 0,60%-ról 0,65%-ra emelkedett. E módszerrel az Al
4,26%, Fe 3,1%, Mg 0,48%; Mn 888, Zn 69, Cu 20 és B 9 mg/kg mennyiségnek
adódott. - Az NH
4
-acetát+EDTA-oldható (Lakanen & Erviö, 1971) frakcióban foszfor hatására
nagyságrenddel nőhet a P, 2-3-szorosára a S és Sr mennyisége a feltalajban. A
meszezett talaj gazdagabb volt Ca, Na, B, Ba és Zn elemekben a meszezőanyag
összetételére visszavezethetően. Szegényebb volt viszont az Al, Fe, Mn, Ni, Pb,
Co és Cr elemeket tekintve, mely fémek inkább a savas közegben oldhatóbbak. - A
K-kontroll talajon mért K
2
O-mennyiség 167-ről 355 mg/kg értékre
emelkedett K-trágyázással. Némileg nőtt a Na-készlet is, mely a K-trágya
összetevője. A Ca, Mg, Mn, Ba és Co oldható mennyisége viszont csökkent.
Feltehetően ezek az antagonista fémek nagyobb kimosódási veszteségeket
szenvedtek, kiszorulva a megkötési helyeikről. - A legkisebb hajtástömeget 4-6
leveles korban nem az abszolút kontroll-, hanem az egyoldalú N-trágyázásban
részesült, erősen elsavanyodott P-hiányos kezelések adták. Az állomány itt
mérgezési tüneteket mutatott. Meszezett talajon a P-hiány kevésbé jelentkezett.
Érés idejére a P-hatások elmaradtak és a meszezés befolyása is mérséklődött, a
növény gyökerei a mélyebb és kevésbé savanyú közegben fejlődhettek.
Meghatározóvá a N-adag vált, 4 t/ha terméstöbbletet eredményezve, míg a
meszezés utóhatásaként 2 t/ha terméstöbbletet regisztráltunk. A K-trágyázás
hatástalan maradt ezen a káliummal jól ellátott termőhelyen. - A 4-6 leveles
kukorica hajtása levéldiagnosztikai szempontból kielégítő ellátottságot jelzett
a N-, K-, Ca-, Mg-, Mn-, Zn-, Cu- és B-koncentrációt tekintve. A P-trágyázás és
a meszezés egyaránt javította a foszfor beépülését a növénybe, így az e_r
Összehasonlító vizsgálatok a talajok kationcsere-kapacitására
Authors: Hegymegi Péter , Simon Barbara , Michéli Erika
Published: June 2007

A talaj kicserélhető
kationjainak minőségi és mennyiségi meghatározására többféle módszert
használnak a gyakorlatban. A módszerek többek között abban különböznek
egymástól, hogy az ioncserét más-más kémhatású közegben vizsgálják. Mivel a
kationcserélő-képesség kémhatástól függő tulajdonság, így a vizsgálatok
eredményeit csak akkor lehet közvetlenül összehasonlítani egymással, ha azt
azonos módszerrel végezték. Magyarországon a Mehlich-módszerként ismert
vizsgálati eljárás terjedt el a kationcsere-kapacitás meghatározására. A
nemzetközi gyakorlatban viszont - többek között - egy másik, az úgynevezett
Grove-módszer használatos. Vizsgálataink igazolták, hogy a két módszer
eredményei azonos talajok esetén eltérnek egymástól. Az eltérések
összefüggésben vannak a talajkolloidok mennyiségével és minőségével. Az
eltérések nagysága elsősorban a minták szervesanyag-tartalmának növekedésével
nőtt, az agyagtartalom által befolyásolt különbség a módszerek között, nem volt
szignifikáns. A T-érték a különböző talajosztályozási rendszerekben fontos
diagnosztikai paraméter, melynek meghatározására nemzetközileg a Grove-módszert
használják. Ezek alapján indokolt lenne egy átszámítási módszer kidolgozása,
amellyel a két eljárás eredménye átszámítható egymásba. Ezen kívül szintén indokolt
az eredeti Grove-módszer elterjedésének szorgalmazása hazánkban.
Eltemetett humuszos talajrétegek előfordulása a Szigetközben és környékén
Authors: Szűcs Mihály , Szűcs Mihályné
Published: June 2007

Összegyűjtöttük a
Szigetközre vonatkozó és az eltemetett rétegek kimutatását is lehetővé tevő
talajfeltárások adatait és azokat szükség szerint további helyszíni
vizsgálatokkal egészítettük ki. A használható korábbi feltárások helyei a
Szigetközben egyenetlenül oszlanak el, a Mosoni-síkságon pedig majdnem teljesen
hiányoznak, ezért ott különösen sok kiegészítő vizsgálatra volt szükség. Végül
több mint 2000 talajszelvény 150 cm mélységig terjedő vizsgálatának adatsorait
tekintettük át. A feltárások helyeinek koordinátáit digitális állományba
rögzítettük. Saját feltárásaink helyeit GPS segítségével azonosítottuk, a más
forrásból származó korábbi feltárások koordinátáit talajtérképek és topográfiai
térképek egybevetésével határoztuk meg. A digitalizált pontokból térinformatikai
szoftver segítségével, Thiessen poli-gonok képzése útján állítottuk elő a
folthatárokat. Az eltemetett humuszos talajrétegek vizsgálata során
megállapítottuk, hogy azok többnyire mélyen helyezkednek el, humusztartalmuk
általában nem nagyobb, mint a feltalajé, foszforhiányosak, biológiailag
inaktívak, oldható mikroelem-tartalmuk réti dinamikára utal. Környezetvédelmi
szempontokat is figyelembe véve, jelenlegi helyzetükben hagyásukat tartjuk
célszerűnek. Az elvégzett radiokarbon meghatározások alapján megállapítható,
hogy az eltemetett rétegek keletkezése a különböző helyszíneken 3-4 ezer éves
időtartamban történhetett. A területi elterjedésre vonatkozóan megállapítottuk,
hogy foltokban vannak ugyan, de összes területük a Szigetköz mintegy 20%-át
lefedi a korábbi 3-4%-os becsléssel szemben. A Szigetköz belső területén az
eltemetett humuszos rétegű foltok félköríves, vagy orsós elrendeződését véltük
felfedezni. A Mosoni-síkságon Bezenyétől Kimléig a Mosoni-Duna mentén alkotnak
majdnem teljesen összefüggő sávot. Kimlétől Öttevényig ez a sáv félkörívben
egészen Lébényig, a Rábca hordalékkúpjáig jut el, megkerülve a Mecsér alatt
lévő nagy pleisztocén eredetű foltot.
Az erdőtalaj-képződés ásványtani vonatkozásai a Visegrádi-hegységben, a pilisszentlászlói mintaterületek eruptív anyakőzet összletein
Authors: Kalmár János , Petrescu Iustinian , Szendreiné Koren Eszter
Published: June 2007

A Visegrádi-hegység
területén létesített két mintaterületen, a nyolc talajszelvényben -
talajtípusukat tekintve - a déli kitettségben savanyú barna erdőtalajok, ill.
erubáz és savanyú barna erdőtalaj átmenete, míg az északi kitettségű
parcellákban podzolos barna erdőtalajok, savanyú barna erdőtalaj és ranker
jelenik meg. Itt meg kell jegyezni, hogy az erdő termőrétegét képező
lejtőüledék tulajdonképpen számos, mindössze pár tíz cm vastag, különböző
összetételű, lencsés kifejlődésű, egymásra települő talajrétegből áll, változó
mennyiségű kőzettörmelékkel. A feltárt talajrétegek komplex vizsgálata során
kimutattuk, hogy a talaj vázanyagát alkotó üledék főleg homokos-iszapos
(kőzetlisztes) jellegű, nagy mennyiségű törmelékkel, amely a közvetlen alatta
fekvő vulkáni kőzetekből (andezit láva és piroklasztit) származnak. A
szemcseeloszlás alapján kimutatható, hogy a szelvények nagy részében létezett
egy deszcendens agyagfrakció-dúsulás. A törmelékszemcsék mikroszkópos
vizsgálata kimutatta, hogy az andezit mállása jelenleg is folyamatban van, a
talajképződés részeként. A talaj finom frakciójában megjelenő agyagásványok,
így a montmorillonit, az illit és az illit/szmektit kevertszerkezetű ásvány,
részben az andezit hidrotermális elváltozása, részben a talajtani folyamatok
során keletkeztek. Feltételezhető, hogy a talajban kis mennyiségben megjelenő
szilánkos kvarcszemcsék és a muszkovit-lemezek eolikus eredetűek.
Az egyes mintákon végzett pollenanalízis alapján
megállapítható, hogy a jelenlegi talajszelvény a holocén PB/BO átmenettől az AT
fázis kevert tölgy pollenszintje között folyamatosan keletkezett. Ez
korrelálható az egyik szelvényben talált faszén
14
C
kormeghatározásával.
Cu-, Pb- és Cd-adszorpció hatása a talajmontmorillonit kristályszerkezetére és szerkezeti duzzadására
Authors: Németh Tibor , Sipos Péter , Tóth Mária , Mohai Ilona
Published: June 2007

Talajmontmorilloniton végzett adszorpciós
kísérleteink újabb adatokkal támasztották alá, hogy a montmorillonitok valóban
nagy mennyiségben képesek fémionokat megkötni, s ezáltal rendkívül jelentős
szerepük van a talajban lejátszódó kémiai folyamatokban, a nyomelemek és
szennyezők talajbeli mozgásában.
A különböző fémionokkal adszorbeált
montmorillonit röntgendiffrakciós vizsgálata megerősítette azt a tényt, hogy a
rétegközi kation természete alapjaiban befolyásolhatja a szmektitek
legszembetűnőbb szerkezeti vonását, a bázistávolságot. A Cu- és Pb-adszorbeált
montmorillonitok bazális rácssíktávolsága 12,5, ill. 13 Ǻ, mely a víz
egyrétegű elrendeződésére utal a rétegközi térben. Ezzel szemben a Cd
2+
a
kétrétegű kationoknak megfelelő két vízrétegű formában adszorbeálódott a
montmorillonit rétegközi terében. Az adszorbeált kation kémiai természetén
felül egyértelműen lényeges tényező ebben az is, hogy az adott fémion mekkora
koncentrációban van jelen a montmorillonittal kölcsönhatásban lévő oldatban.
Glicerines
kezelés után a Cu- és Pb-adszorbeált montmorillonit-minták duzzadásvesztést
mutatnak, míg a kadmiumadszorpció nem változtatja meg a talajmont-morillonit
duzzadóképességét. Az egyébként duzzadó vermikulitok megkülönböztető sajátsága
az, hogy viszonylag nagy rétegtöltésüknek köszönhetően rétegközi terükbe csak
egy glicerinréteget képesek magukba fogadni, mert a 2:1 szilikát egységeket
összekapcsoló erő meghaladja a szmektitekét. A vizsgált montmorillonit tehát
nagyobb réz-, illetve ólomterhelésre nemcsak hogy elveszti kristályrácson
belüli duzzadóképességét, de adott esetben fémmel szennyezett talajban könnyen
félre is határozható vermikulitnak.
Large reinforced-concrete deep beams with web openings: test and strut-and-tie results
Authors: Hu O. E. , Tan K. H.
Published: June 2007

This paper investigates the behaviour and shear strength of large reinforced-concrete deep beams with web openings. A total of three pierced deep beams and a solid beam with compressive strengths in the range 35 MPa ≤ f′c ≤ 44 MPa are reported, which were tested to failure under two-point symmetric top loading to determine their ultimate shear strengths. All the four beams had an overall depth of 2000 mm, an overall length of 4000 mm and a web thickness of 220 mm, which were probably the largest pierced deep beam specimens tested so far. They represent very valuable test data for verifications of code predictions or strut-and-tie results. Web openings of the same size were located in the shear span of three pierced beams. The only difference among the three pierced beams was that their shear spans ranged from 500 to 900 mm. Test results show that a web opening can reduce the ultimate strength of a large deep beam significantly, if the web opening intersects the force path between the load point and the support. The observed crack patterns clearly illustrate a strut-and-tie system in large pierced deep beams. An improved strut-and-tie approach is also presented in the current paper to predict the ultimate shear strength.
Late Hormonal Levels, Semen Parameters, and Presence of Antisperm Antibodies in Patients Treated for Testicular Torsion
Authors: Arap Marco A. , Vicentini Fabio C. , Cocuzza Marcello , Hallak Jorge , Athayde Kelly , Lucon Antonio M. , Arap Sami , Srougi Miguel
Published: June 2007

ABSTRACT: In spite of prompt diagnosis and either orchiectomy or preservation of the affected testis, infertility remains a significant sequel to testicular torsion. The objective of this study was to evaluate the late endocrine profile, seminal parameters, and antisperm antibody levels after testicular torsion. We also analyzed the impact of orchiectomy or detorsion on the organ fate. Of 24 patients evaluated after testicular torsion, 15 were treated with orchiectomy (group 1) and 9 were treated with orchiopexy (group 2). All subjects were assessed by semen analysis, endocrine profile (levels of follicle‐stimulating hormone, luteinizing hormone, and testosterone), and seminal antisperm antibody levels. A group of 20 proven fertile men was used as the control. Median ischemia time in group 1 (48 hours) was significantly higher than in group 2 (7 hours). Both groups demonstrated decreases in sperm count and morphology compared with controls. Group 1 showed a significantly higher motility than group 2 (P = .02). Group 1 also showed a significantly better morphology by World Health Organization and Kruger criteria than group 2 (P = .01). All patients presented endocrine profiles within the normal range, and no significant differences in antisperm antibody levels were detected between the groups. However, a trend for higher levels was found in patients treated for testicular torsion, regardless of the fate of the testis. Moreover, no significant correlation was found between antisperm antibody levels and age at torsion, ischemia time, seminal parameters, or treatment applied. In conclusion, we found that after torsion patients maintain late hormonal levels within the normal range. Testicular fate did not have any correlation with the formation of antisperm antibodies. Although sperm quality was preserved in most of the patients with the exception of sperm morphology, patients treated with orchiectomy presented better motility and morphology compared with the detorsion group. Further studies may clarify whether maintenance of a severely ischemic testicle may impair testicular function.
Social and Psychological Factors in the Academic Achievement of Children of Immigrants: A Cultural History Puzzle
Authors: Portes Pedro R.
Published: June 2007

The influence of various factors in immigrant students' school achievement was examined in informing broader discourses on schooling, inequality, and related conceptual issues. The ways in which different types of predictors of school achievement behave in context with factors related to adolescence and cultural adaptation in a sample of children of immigrants were explored. The influence of cultural background remains enigmatic and could not be disaggregated entirely by key demographic and sociopsychological factors considered in this study. The latter explained almost 40% of the variation in student achievement. The two groups found to excel in American schools (Asian and Cuban) have more established inroads in the community and may be able to provide greater social and cognitive support. The lowest achievers were from groups that have the least support, encounter language problems in school, and felt most unwelcomed by the mainstream. The cultural compatibility between each group and the school context appears to vary in systematic ways and is addressed in a model proposed in the article.
The Dynamics of School Change: Response to the Article, “Comer's School Development Program in Prince George's County, Maryland: A Theory-Based Evaluation,” by Thomas D. Cook et al
Authors: Comer James P. , Haynes Norris M.
Published: June 2007

The essential findings of Thomas Cook and colleagues in their article, "Comer's School Development Program in Prince George's County, Maryland: A Theory - Based Evaluation," are expressed in their abstract as follows:

A randomized experiment of Comer's School Development Program was conducted in 23 middle schools .... [This study] showed that Comer schools implemented some [but not all] of the program's central elements better than control schools .... This shortfall in program implementation may have been responsible for students in the experimental schools not changing any more than controls. Quasi-experimental analyses showed that the program theory may be correct in many of its predictions about student changes .... However, achievement gains were found in schools with a more explicit academic focus, suggesting that improving this focus should be as central to Comer's program theory as improving a school's social climate. Even more needed, though, are ways to improve program implementability, the sine qua non for student change.

The study, as conducted, was not an evaluation of the School Development Program (SDP) organization or the process. It was a limited study of the effects of one application of the SDP process: using an experimental control