bluuebunny/crossref_metadata_2025 huggingface dataset:
Classification of Asphyxia: The Need for Standardization
Authors: Sauvageau Anny , Boghossian Elie
Published: June 2010

Abstract: The classification of asphyxia and the definitions of subtypes are far from being uniform, varying widely from one textbook to another and from one paper to the next. Unfortunately, similar research designs can lead to totally different results depending on the definitions used. Closely comparable cases are called differently by equally competent forensic pathologists. This study highlights the discrepancies between authors and tries to draw mainstream definitions, to propose a unified system of classification. It is proposed to classify asphyxia in forensic context in four main categories: suffocation, strangulation, mechanical asphyxia, and drowning. Suffocation subdivides in smothering, choking, and confined spaces/entrapment/vitiated atmosphere. Strangulation includes three separate forms: ligature strangulation, hanging, and manual strangulation. As for mechanical asphyxia, it encompasses positional asphyxia as well as traumatic asphyxia. The rationales behind this proposed unified model are discussed.
Recurrent Pregnancy Loss and Apolipoprotein E Gene Polymorphisms: A Case–Control Study from North India
Authors: Agarwal Meenal , Parveen Farah , Faridi Rehan Mujeeb , Phadke Shubha R. , Das Vinita , Agrawal Suraksha
Published: June 2010

Citation Agarwal M, Parveen F, Faridi RM, Phadke SR, Das V, Agrawal S. Recurrent pregnancy loss and apolipoprotein E gene polymorphisms: a case–control study from North India. Am J Reprod Immunol 2010; 64: 172–178

Problem  The role of apolipoprotein E gene polymorphisms in the etiology of recurrent pregnancy loss (RPL) is not clearly understood. We evaluated this polymorphism in unexplained pregnancy losses among North Indian women.

Method of study  In a retrospective case–control study, 200 well‐characterized RPL cases were examined for their APO‐E genotypes based on restriction fragment length polymorphism analysis of PCR‐amplified fragments including amino acid positions 112 and 158. The observed genotypes were compared with those obtained from an equal number of ethnically matched negative controls.

Results  We found similar APO‐E genotypes and E2, E3, and E4 allele frequency distribution among RPL patients and controls. The allele frequencies obtained in patients and controls respectively were as follows: E2 = 7.5% and 9.0% (P = 0.52; OR = 0.81; 95%CI = 0.49–1.35), E3 = 89.7% and 90% (P = 1.00; OR = 0.97; 95%CI = 0.61–1.54), and E4 = 2.8% and 1% (P = 0.12; OR = 2.79; 95%CI = 0.88–8.86).

Conclusions  Our data did not support the association of APO‐E gene polymorphisms with recurrent pregnancy loss as reported by some of the previous studies. We endorse adequate characterization of RPL cases, inclusion of appropriate negative controls, and adequate sample size prior to addressing such studies.
Clinical signs and CRP values associated with blood culture results in neonates evaluated for suspected sepsis
Authors: Ohlin Andreas , Björkqvist Maria , Montgomery Scott M , Schollin Jens
Published: June 2010

Aim:  To identify which clinical signs at presentation are most predictive of sepsis subsequently confirmed by blood culture and to investigate whether the predictive power of the clinical signs varies by gestational age.

Methods:  Among 401 newborn infants <28 days of age with suspected sepsis, nine signs of sepsis and C‐reactive protein (CRP) values were prospectively recorded. Logistic regression assessed the association of these signs and laboratory values with a subsequently confirmed diagnosis of sepsis by positive blood culture. The analysis was stratified by gestational age with mutual simultaneous adjustment for the signs and sex.

Results:  Five of the nine clinical signs (feeding intolerance, distended abdomen, blood pressure, bradycardia and apnoea), along with CRP were statistically significantly associated with a positive blood culture. After simultaneous adjustment for all of the signs, apnoea, hypotension and CRP were independently predictive of positive blood culture. When the material was stratified by gestational age, differences in the association with positive blood culture were found for bradycardia, tachypnea and irritability/seizures.

Conclusion:  In this selected population of infants with suspected sepsis, apnoea and hypotension are independently predictive of a confirmed diagnosis, while bradycardia is more predictive among preterm infants and tachypnea among term infants.
Assessment and Characterization of Purinergic Contractions and Relaxations in the Rat Urinary Bladder
Authors: Aronsson Patrik , Andersson Michael , Ericsson Therese , Giglio Daniel
Published: June 2010

Abstract: The aim of the present study was to assess the purinoceptor functional responses of the urinary bladder by using isolated rat urinary bladder strip preparations. ATP elicited a transient bladder contraction followed by a sustained relaxation and ADP, UDP and UTP generated predominantly potent relaxations (relaxatory potencies: ADP = ATP > UDP = UTP). The ATP contractions were desensitized with the P2X1/3purinoceptor agonist/desensitizer α,β‐meATP and reduced by the P2 purinoceptor antagonist PPADS but unaffected by the P2 purinoceptor antagonist suramin. Electrical field stimulation (1–60 Hz) evoked frequency‐dependent bladder contractions that were decreased by incubation with α,β‐meATP but not further decreased by PPADS. Suramin antagonized relaxations generated by UDP but not those by ADP, ATP or UTP. PPADS antagonized and tended to antagonize UTP and UDP relaxations, respectively, but did neither affect ADP nor ATP relaxations. ADP relaxations were insensitive to the P2Y1purinoceptor antagonist MRS 2179 and the ATP‐sensitive potassium channel antagonist glibenclamide. The ATP relaxations were inhibited by the P1 purinoceptor antagonist 8‐p‐sulfophenyltheophylline but unaffected by the A2A adenosine receptor antagonist 8‐(3‐chlorostyryl)caffeine and glibenclamide. Adenosine evoked relaxations that were antagonized by the A2B adenosine receptor antagonist PSB 1115. Thus, in the rat urinary bladder purinergic contractions are elicited predominantly by stimulation of the P2X1purinoceptors, while UDP/UTP‐sensitive P2Y purinoceptor(s) and P1 purinoceptors of the A2B adenosine receptor subtype are involved in bladder relaxation.
Sexual Desire and the Female Sexual Function Index (FSFI): A Sexual Desire Cutpoint for Clinical Interpretation of the FSFI in Women with and without Hypoactive Sexual Desire Disorder
Authors: Gerstenberger Eric P. , Rosen Raymond C. , Brewer Jessica V. , Meston Cindy M. , Brotto Lori A. , Wiegel Markus , Sand Michael
Published: June 2010

Introduction

A validated cutpoint for the total Female Sexual Function Index scale score exists to classify women with and without sexual dysfunction. However, there is no sexual desire (SD) domain-specific cutpoint for assessing the presence of diminished desire in women with or without a sexual desire problem.

Aims

This article defines and validates a specific cutpoint on the SD domain for differentiating women with and without hypoactive sexual desire disorder (HSDD).

Methods

Eight datasets (618 women) were included in the development dataset. Four independent datasets (892 women) were used in the validation portion of the study.

Main Outcome Measures

Diagnosis of HSDD was clinician-derived. Receiver-operator characteristic (ROC) curves were used to develop the cutpoint, which was confirmed in the validation dataset.

Results

The use of a diagnostic cutpoint for classifying women with SD scores of 5 or less on the SD domain as having HSDD and those with SD scores of 6 or more as not having HSDD maximized diagnostic sensitivity and specificity. In the development sample, the sensitivity and specificity for predicting HSDD (with or without other conditions) were 75% and 84%, respectively, and the corresponding sensitivity and specificity in the validation sample were 92% and 89%, respectively.

Conclusions

These analyses support the diagnostic accuracy of the SD domain for use in future observational studies and clinical trials of HSDD.
Characteristics of Vibrator Use by Gay and Bisexually Identified Men in the United States
Authors: Reece Michael , Rosenberger Joshua G. , Schick Vanessa , Herbenick Debby , Dodge Brian , Novak David S.
Published: June 2010

Introduction

Recent reports indicate that vibrator use during solo and partnered sexual activities is common among heterosexual men and women in the United States. However, little research has comprehensively assessed vibrator use among gay and bisexually identified men.

Aims

This study sought to document the extent to which gay and bisexually identified men report using vibrators, the sexual and relational situations within which they use them, and how men use vibrators on their own and their partners’ bodies.

Methods

Data were collected from 25,294 gay and bisexually identified men from 50 U.S. states and from the District of Columbia via an internet-based survey.

Main Outcome Measure

Measures included sociodemographics, health-related indicators, sexual behaviors, and those related to recent and past use of vibrators during solo and partnered sexual interactions with other men.

Results

Approximately half (49.8%) of gay and bisexually identified men reported having used vibrators. Most men who had used a vibrator in the past reported use during masturbation (86.2%). When used during partnered interactions, vibrators were incorporated into foreplay (65.9%) and intercourse (59.4%). Men reported frequent insertion of vibrators into the anus or rectum when using them during masturbation (87.3%), which was also common during partnered interactions (~60%), but varied slightly for casual and relationship sex partners. For both masturbation and partnered interactions, men overwhelmingly endorsed the extent to which vibrator use contributed to sexual arousal, orgasm, and pleasure.

Conclusions

Vibrator use during both solo and partnered sexual acts was common among the gay and bisexually identified men in this sample and was described by men as adding to the quality of their sexual experiences.
Time course of vasovagal syncope with whole blood donation
Authors: Tomasulo P. , Bravo M. , Kamel H.
Published: June 2010

Background  Improving the safety of the donation experience will reduce donor injuries and increase donations, donation frequency and donor satisfaction. Understanding the physiology of donor reactions supports selection of effective interventions to reduce risk.

Aims  The examination of the time course of donor vasovagal syncopal reactions (VVS) to determine when most reactions occur supports the development of appropriate theories about cause of the majority of the reactions and the application of interventions to reduce the risk of a significant number of reactions.

Materials and Methods  A database of more than 900 000 donor registrations and more than 500 000 whole blood donation events was examined for the time course of VVS reactions by reviewing the onset time of the reactions. The donor experience was divided into three periods based on the theory that the risk of reaction depends on different factors in each of the periods. The time course was analyzed using frequency distribution counts stratified by donation status and separately by gender.

Results  There were 956 766 registrations, 554 513 attempted whole blood donations, 536 907 complete donations and 17 606 incomplete donations. The mean draw time of a complete donation was 8.21 (95% CI, 8.2–8.21) min and for an incomplete donation was 8.91 (95% CI, 8.8–9.01) min. The reaction rate for Period 1 (before venipuncture) was 0.045/1000 registrations; for Period 2 (venipuncture to 4 min post‐venipuncture) and Period 3 (4 min post venipuncture to last reported VVS reaction ‐265 min), the reaction rate was 3.5/1000 for women and 1.5/1000 for men. There was a steady increase in the reaction rate during phlebotomy and the rate peaked at the time of needle removal. After needle removal there were peaks in the VVS rate at 5 and 9 min. The reaction rate declined steadily thereafter.

Discussion  The peak reaction rates occur within a time period of 10 min beginning 1 min before needle removal. The reactions which have the most significant risk of donor injury occur later than this and often occur after the donor leaves the donation site. Approximately 10% of VVS reactions in male donors and 25% of VVS reactions in female donors occur more than 15 min after the needle is removed. The latest VVS reaction was reported to have begun at about 4.5 h after needle withdrawal.

Conclusion  It is our thought that preventive interventions for reactions which occur during phlebotomy might be slightly different from the preventive measure aimed at reducing risk to donors after assuming upright posture. Once the donor stands up, relative hypovolemia plays a greater role and interventions should be aimed at preventing changes in blood pressure due to hypovolemia during this period.
Blood donor motivation: what is ethical? What works?
Authors: Stutzer A. , Goette L.
Published: June 2010

The retention of previous donors and the recruitment of new donors is a serious challenge for many blood donation services in their effort to prevent blood shortages. More and more services make use of some sort of donation incentives. However, the use of (material) incentives to motivate blood donors is fiercely controversial, and there is a longstanding (ethical) debate about whether it should be allowed that donors receive material rewards. Interestingly, this debate is dealt with in almost complete absence of systematic empirical evidence on the effectiveness of material incentives in encouraging people to donate. In this article, we argue that the discussion on what is ethical in motivating blood donors should be enriched with empirical evidence based on field experiments. We confront the Titmuss controversy with recent results from an experiment administering lottery tickets as a motivation device. Moreover, we take up a neglected phenomenon in the study of blood donors: many nondonors are not principally against donating blood; they have just never made up their mind about becoming active blood donors. We propose active decisions as a mechanism to transform latent prosocial preferences into actual prosocial behaviour.
Blood groups: genetics and physiology
Authors: Cartron J.‐P.
Published: June 2010

Numerous studies in biochemistry, genetics and molecular biology conducted over two decades have shown that blood group gene products expressed on red cells and various tissues exhibit a variety of potential functions, which can be schematically classified into functional groups such as transporters and channels, receptors, adhesion molecules, enzymes or structural components, with a further level of complexity as a same molecule may exhibit multiple functions. As structures present on red cells, blood group and blood group‐related molecules may contribute to the structure and function of the red cell membrane and may help to clarify unresolved biological processes (for instance, water and gas transport through biological membranes). Alternatively, some of these molecules may simply be the witnesses of a residual persistence of membrane components during erythroid cell differentiation with no significant function. Investigation of blood group and blood group‐related molecules as structures present on epithelial or endothelial cells of tissues and organs has revealed other features of their potential physiological role and led to the discovery of some unexpected functions (for instance Fy‐mediated transcytose). Increasing our knowledge on both aspects is of interest not only for transfusion medicine, but also for transplantation and for understanding the normal physiology and physiopathology of several diseases. Current studies indicate that blood group and blood group‐related molecules cover large areas of human physiology from cerebral to renal and reproduction biology. As specific deficiencies of these molecules have only a minor or no detrimental effect in most instances, they are either dispensable for cell function or redundant. In some instances, however, a function becomes apparent under stress or in pathological conditions. How common and rare blood group polymorphisms are maintained and may impact function is largely unknown, although a few examples clearly point to selective pressure exerted by pathogenic micro‐organisms. Despite significant progress, much remains to be discovered to clearly delineate how blood group molecules, alone or as molecular complexes in erythroid and non‐erythroid cells, may act in health and disease, to understand the underlying mechanisms, and, ultimately, how these findings might eventually be translated into clinical applications.
Blood group antigens and immune responses–detailed knowledge is necessary to prevent immunization and to follow up immunized individuals
Authors: Husebekk A. , Ahlen M. T. , Killie M. K. , Tiller H. , Eksteen M. , Killie I. L. , Heide G. , Kjeldsen‐Kragh J. , Skogen B. , Stuge T. B.
Published: June 2010

Background  The immune system is educated to detect and react with foreign antigens and to tolerate self‐antigen. Transfusion of blood cells and plasma and pregnancies challenge the immune system by the introduction of foreign antigens. The antigens may cause an immune response, but in many instances this is not the case and the individual is not immunised after exposure of blood group antigens.

Aims  The aim of the presentation is to dissect some immune responses to blood group antigens in order to understand the mechanism of immunisation.

Methods  The results of immune responses to blood group antigens can be detected by the presence of antibodies to the antigens. If the antibodies are of IgG class, the activated B cells have received help from antigen specific T cells. Both antibodies, B cells and T cells can be isolated from immunised individuals and studied in the laboratory. Also B‐cell receptors and T‐cell receptors as well as MHC molecules on antigen presenting cells can be studied and models of the immune synapses can be created in vitro.

Results  The most classic immune responses in transfusion medicine and in incompatible pregnancies are immune responses to the RhD antigen on red cells, HLA class I molecules on white cells and platelets and human platelet antigens. The nature of these antigens are different; RhD antigens are part of a large complex, present on red cells from RhD positive individuals and completely lacking on red cells from RhD negative individuals. It is likely that many peptides derived from this antigen complex may stimulate T cells and B cells. HLA antigens are highly polymorphic and the antigens are known to induce strong alloimmune responses. The HPA antigens are created by one amino acid difference in allotypes based on a single nucleotide polymorphism at the genetic level. HPA 1a induce immune responses in 10% of HPA 1b homozygote pregnant women. The result of these immune responses is destruction of blood cells with clinical consequences connected to the effect of transfusions or the outcome of pregnancies.

Summary/Conclusions  Even though there is emerging knowledge about the immune responses to some of the blood group antigens, more information must be gained in order to understand the complete picture. The action of the innate immune response initiating the adaptive immune response to blood group antigens is not well understood. A detailed understanding of both the innate ad the adaptive part of the immune response is necessary to identify individuals at risk for immunisation and to prevent immunisation to blood group antigens.
Multicomponent apheresis
Authors: Zingsem Jürgen
Published: June 2010

Introduction:  An increasing demand for blood components is opposed by a decreasing donor availability for the collection of the required blood components. Furthermore, current stem cell transplantation regiments require the collection of more than one similar or different component from one donor or patient. One strategy for maintaining the patients’ supply with the required blood components can be the concurrent collection of more than one component from one donor by apheresis, thus multicomponent apheresis.

Scope of multicomponent combinations:  Combinations are possible for nearly every kind of blood components. In one session it is possible – depending on the apheresis device – to collect up to four plasma units alone, one or more plasma units and one or two red blood cell (RBC) units, one or more plasma units and one or more platelet units, one or more plasma units and one or two RBC units and one or more platelet units, one or two RBC units and one or more platelet units, two RBC units alone, one or more platelet units.

Also in leucocytapheresis the collection of more than one blood component has become a routine procedure. Performing allogeneic stem cell apheresis can lead to a cell dose for two transplantations or to one unit of PBSCs and concurrently collected and frozen mononuclear cells used for donor lymphocyte infusions therapy. Autologous mononuclear cell products (e.g. PBSCs or monocytes for dendritic cell generation) usually are cryoconserved before use and require additional plasmaproteins for cryoconservation. The latter can be obtained by the concurrent collection of plasma during leucocytapheresis. Thus, the combination of cell and plasma units or of cell units of different dose or for different purpose are further examples for the implementation of multicomponent apheresis in tumor therapy.

Conclusions:  The understanding of apheresis technologies facilitates the use of multicomponent apheresis in the vast application field for tailoring the kind, quantity, and quality of blood components for patient care.
Improving blood donor screening by nucleic acid technology (NAT)
Authors: Schmidt M. , Seifried E.
Published: June 2010

The description of the ABO blood group system by Landsteiner and coworkers marked a sea change in making blood transfusions feasible and safe for a broad range of indications. Nevertheless, with an increase in blood transfusions, side‐effects such as transfusion‐transmitted infections (TTIs) became more and more important. A major challenge in transfusion medicine was (and is) to develop screening assays with maximum analytical sensitivity and analytical specificity to reduce the diagnostic window period as much as possible. Until the late 1990s, blood screening for TTIs depended entirely on serological assays. Except for HBV, where the virus can be detected using HBs‐antigen assays, tests for the detection of other TTIs relied almost exclusively on antibody detection. These tests, however, are associated with a relatively long diagnostic window period because they detect the response of the immune system to an infection.
Regulation of cell‐based medicine: the European experience
Authors: Rebulla P. , Montemurro T. , Giordano R.
Published: June 2010

Cell‐based medicine is regulated in Europe by Regulation no. 1394/2007 of the European Parliament and of the Council. This regulation defines a new category of products named ‘advanced therapy medicinal products’ and provides rules for their marketing authorization, instructions for the definition of product characteristics, specifications on product labelling and product package leaflet. Moreover, it defines the types of cell or tissue manipulations that are not associated to the category of ‘engineered’ cells or tissues. Finally, it describes the composition and function of the Committee for Advanced Therapies, which can be consulted for the categorization of novel biomedicine products.
Stem cell and cord blood transplantation – state of the art
Authors: Bug G. , Serve H.
Published: June 2010

Recent advances have broadened the application of allogeneic hematopoietic stem cell (HSC) transplantation and contributed to the continuously increasing numbers of transplantations performed worldwide. These include (1) greater utilization of reduced intensity conditioning and improvement of supportive care allowing transplantation of patients up to 70 years of age and with pre‐existing medical problems, and (2) expansion of the acceptable stem cell donor pool to unrelated cord blood HSC. Thus, selection of the particular transplant procedure should be guided by patient characteristics such as type and stage of the disease, previous therapies, age and comorbidities. HLA typing of patient and siblings at diagnosis is essential to allow the timely initiation of an unrelated donor search if needed.
Regulation of cell‐based medicine – the German experience
Authors: Weisbach V.
Published: June 2010

In the member states of the European Union, the field of cell‐based medicine and tissue preparations is determined by the law of the European Community (EC). The implementation of the EC directives is mandatory and makes Community law binding in the EU Member States. The Tissues and Cells Act of July 20, 2007 transposed the Directive 2004/23/EC, which is setting standards for human tissues and cells, into German law. This Tissue Act is not a law on its own, but makes significant amendments of the Medicinal Products Act, the Transplantation Act and the Transfusion Act. According to the Amsterdam Treaty (1997) and the Directive 2004/23/EC itself, the national legislators may stipulate stricter provisions, thus exceeding the minimum requirements specified in this EC directive. Accordingly, a real harmonization of the standards for human tissues and cells within the European Union is not intended and not possible. The Directive 2004/23/EC includes minimum standards to ensure high quality and safety margins for human tissues and cell preparations released for clinical application in humans. The standards cover the donation, procurement, testing, processing, preservation, storage, and distribution of human tissues and cells. The German Tissue Act defines tissues and cell preparations as pharmaceutical drugs governed by the German Drug Act. The need for high standards in quality and safety is highlighted, most of the loopholes that might otherwise allow operation outside national drug legislation in the field of local tissue banking and tissue engineering have been closed. As a consequence, donated tissues and stem cell preparations are subjected to strict regulations which mainly aim to prevent the most serious adverse effects of allogeneic tissue transplants, the transmission of infectious pathogens. Whenever possible, a validated inactivation procedure should be included in the manufacturing process. Tissues and stem cell preparations now usually require national approval, a procedure which in principle is comparable, although somewhat simplified, to the well‐established national licensing procedure for blood components seeking post‐marketing approval from the national authorities (Paul Ehrlich Institute). According to the highly positive experiences obtained with the standardization and licensing of blood components combined with a local and national system for surveillance, it can be expected that the national approval and local and national surveillance of stem cell and tissue preparations will contribute to a significantly improved quality and higher safety profile for the patients. However, the bureaucratic efforts which are inevitable consequences of the new regulations are still a matter of some dispute.
Volunteer safer than replacement donor blood: a myth revealed by evidence
Authors: Allain J.‐P.
Published: June 2010

The dogma that volunteer non‐remunerated blood donors (VNRD) are safer has been a cornerstone of world transfusion, including developing countries, for WHO and other major transfusion organizations although the data supporting this dogma has never been convincing. It was supported by data collected without regard for the basic rule of epidemiology, which is to compare what is comparable. In this case, first‐time and repeat VNRD were amalgamated, and genuine replacement/family donors (R/F) were mixed with paid donors. In sub‐Saharan Africa (SSA), VNRD and R/F donors have a median age of < 20 and around 30, respectively. In VNRD, the proportion of females is considerably higher than in R/F donors further distorting the comparisons. In epidemiological terms, only first‐time VNRD can be validly compared to R/F donors.

When such valid approach is taken, as published by three SSA countries (Cameroon, Ghana and Guinea), no significant difference in the prevalence of anti‐HIV and HBsAg is apparent. In each study, first‐time VNRD > 20 years of age have higher prevalence of HBsAg and sometimes of anti‐HIV than R/F donors. These confirmed preliminary data strongly suggest that first‐time VNRD and R/F donors are epidemiologically undistinguishable and equally safe for viral infections.

This collective data should directly impact three critical factors: the cost of blood, the availability of blood and the efforts put in recruiting repeat donors. R/F blood costs 2–5 times less than VNRD blood, and collecting R/F blood should no longer be discouraged. VNRD‐only policy not only costs more but also limits blood availability for acute anaemia, potentially endangering patients’ lives. Collecting R/F blood as a legitimate supplement to VNRD blood may help reaching 10 units/1000 inhabitants, a level considered adequate for developing countries’ blood supply.

Only repeat donation significantly improves blood viral safety. As a result, not only first‐time VNRD but also R/F donors should be actively encouraged to repeat donation. Evidence should take precedence over a moribund myth.
Sources of variability in greenhouse gas and energy balances for biofuel production: a systematic review
Authors: WHITAKER JEANETTE , LUDLEY KATHERINE E. , ROWE REBECCA , TAYLOR GAIL , HOWARD DAVID C.
Published: June 2010

Across the energy sector, alternatives to fossil fuels are being developed, in response to the dual drivers of climate change and energy security. For transport, biofuels have the greatest potential to replace fossil fuels in the short‐to medium term. However, the ecological benefits of biofuels and the role that their deployment can play in mitigating climate change are being called into question. Life Cycle Assessment (LCA) is a widely used approach that enables the energy and greenhouse gas (GHG) balance of biofuel production to be calculated. Concerns have nevertheless been raised that published data show widely varying and sometimes contradictory results. This review describes a systematic review of GHG emissions and energy balance data from 44 LCA studies of first‐ and second‐generation biofuels. The information collated was used to identify the dominant sources of GHG emissions and energy requirements in biofuel production and the key sources of variability in published LCA data. Our analysis revealed three distinct sources of variation: (1) ‘real’ variability in parameters e.g. cultivation; (2) ‘methodological’ variability due to the implementation of the LCA method; and (3) ‘uncertainty’ due to parameters rarely included and poorly quantified. There is global interest in developing a sustainability assessment protocol for biofuels. Confidence in the results of such an assessment can only be assured if these areas of uncertainty and variability are addressed. A more defined methodology is necessary in order to allow effective and accurate comparison of results. It is also essential that areas of uncertainty such as impacts on soil carbon stocks and fluxes are included in LCA assessments, and that further research is conducted to enable a robust calculation of impacts under different land‐use change scenarios. Without the inclusion of these parameters, we cannot be certain that biofuels are really delivering GHG savings compared with fossil fuels.
Threshold choice and the analysis of protein marking data in long‐distance dispersal studies
Authors: Sivakoff Frances S. , Rosenheim Jay A. , Hagler James R.
Published: June 2010

1. A valuable technique in the study of insect movement is protein marking, a quantitative method where individuals are categorized as marked or unmarked based on the amount of foreign protein detected by an enzyme‐linked immunosorbent assay (ELISA).

2. Whether individuals are considered marked or not is dependent on a threshold value chosen by the experimenter. The traditional method of choosing the threshold accepts some risk of false positives, wherein unmarked individuals are misclassified as marked. The error rate associated with this method, adopted from the rubidium marking literature, relies on assumptions violated by most ELISA data.

3. We critically examined the effect of violating these assumptions on the false positive rate. In long‐distance dispersal studies where the ratio of unmarked to marked insects is high, false positives can seriously bias estimates of insect movement abilities.

4. Simulations demonstrated that the conventional method for choosing a threshold (i) masks the presence of false positives, (ii) results in a 10‐fold higher than expected false positive rate, and (iii) relies on assumptions of normality that are rarely satisfied; non‐normality produces further increases in false positive rates.

5. We provide some solutions by introducing a new procedure for choosing a threshold that decreases the incidence of false positives and allows data to be corrected for anticipated rates of false positives. This methodology should enhance researcher confidence in the data generated from dispersal studies using protein marking techniques.
Identification and Compensation of Dynamic Scale Mismatches in High-Speed End Mill Boring Trajectory on CNC Machines
Authors: Slamani Mohamed , Mayer Rene , Balazinski Marek , Engin Serafettin
Published: June 2010

During high-speed end mill boring, dynamic scale mismatch originates from the difference in the dynamic response of each axis and, at high feedrates, causes a trajectory ovalization along the axis with the fastest dynamic response. To investigate this error, an experimental approach is used at different feedrates and trajectory radii for a high-speed machine tool with linear motor drives. Results show that dynamic scale mismatch causes out-of-roundness and radius size errors. A simple second order model is used successfully to predict the dynamic scale mismatch and a strategy is proposed and tested to compensate it at the G-code level. An experimental trial reveals the usefulness of the approach.
Process Robustness of Hot Embossing Microfluidic Devices
Authors: Eusner Thor , Hale Melinda , Hardt David E.
Published: June 2010

Polymeric substrates have significant advantages over silicon and glass for use in microfluidics. However, before polymer microfluidic devices can be mass produced, it must be shown that the manufacturing method used to create these devices is robust and repeatable. For this paper, a polymer manufacturing process, hot embossing, was used to produce microsized features in polymethylmethacrylate (PMMA) chips. A design of experiments that varied two factors during the hot embossing process (temperature and pressure), was conducted to determine the robustness of hot embossing microsized channels in PMMA. The channel height and width were measured at three sites on each chip, and the results were analyzed in two ways: response surface modeling (RSM) and nested variance analysis. For the RSM analysis, two separate ANOVA tests and regressions were performed on both channel width and channel height to obtain the response surface models between temperature, pressure and the channel width and height. Furthermore, the variance of channel width and height at each design point was determined and then two ANOVA tests and two separate regressions were performed to obtain the response surface models between temperature, pressure and the variance of channel height and channel width. This analysis was used to determine if hot embossing microfluidic devices is a robust process capable of producing quality parts at different operating conditions. The nested variance analysis was used to determine the primary source of the variation in channel height and width. For the nested variance analysis, two separate calculations were performed in order to determine whether the variance of channel width and height is mostly caused by within-chip variance or chip-to-chip variance. The analysis showed that the channel widths and heights were statistically equal across the four different operating points used (the low-temperature, low-pressure point was omitted). The variance of channel width and the variance of channel height remained constant in the desired operating region. Based on this analysis, it was concluded that hot embossing is a robust process for features on the order of 50 μm. Furthermore, the nested variance analysis showed that the variance of channel width and height is mostly caused by site-to-site measurements on a chip rather than between-chip variance. Therefore, it was determined that hot embossing microfluidic devices are repeatable and consistent from chip-to-chip.
High Frequency Correction of Dynamometer for Cutting Force Observation in Milling
Authors: Girardin François , Remond Didier , Rigal Jean-François
Published: June 2010

Piezoelectric dynamometers are widely used for cutting force measurements. Indeed, this device has the largest bandwidth for this kind of measurement. Nevertheless, the behavior of this device is not very well-known and its use is sometimes inappropriate for static and high frequency dynamic measurements. In this paper, a piezoelectric dynamometer is used for cutting force measurements in a milling case. Cutting forces in milling are discontinuous by nature due to successive inward and outward movements of tool-teeth on the workpiece. As a result, a bandwidth criterion based on cutting parameters is defined in order to permit clear observation of the mean oscillation of the cutting force. The frequency response of a dynamometer is then analyzed over a wide frequency range. A 2 kHz bandwidth can be defined for an efficient correction of cutting force. The dynamometer appears to be exploitable for higher frequencies up to at least 16 kHz though a large number of factors must be taken into account in the analysis. Finally, several lateral milling tests are performed by changing cutting speed, feed rate, and lubricant conditions. The correction of measurements permits highlighting certain particularities in the cutting force signals, such as the effect of shock of inward tool-teeth strokes on the workpiece, the specific behavior for outward tool-teeth strokes, and the effect of a lubricant on the variation in cutting forces.
Integrated Two-Photon Polymerization With Nanoimprinting for Direct Digital Nanomanufacturing
Authors: Zhang Wande , Han Li-Hsin , Chen Shaochen
Published: June 2010

In this work, we demonstrate the plausibility of integrating two-photon polymerization (TPP) with nanoimprinting for direct, digital nanomanufacturing. TPP offers manufacturing of nanomolds at a low cost, while the nanoimprinting process using the nanomolds enables massively parallel printing of nanostructures. A Ti:sapphire femtosecond laser (800 nm wavelength, 100 fs pulse width, at a repetition rate of 80 MHz) was used to induce TPP in dipentaerythritol pentaacrylate to fabricate the nanoimprinting mold with 400 nm wide line array on a glass substrate. The mold surface was silanized by tridecafuoro-1,1,2,2-tetrahydrooctyl-1 trichlorosilane to facilitate the detachment of the mold from the imprinted material. This mold was then used to imprint poly(ethylene glycol) diacrylate (PEGDA). PEGDA is an important biomaterial for many applications such as tissue scaffolds for cell growth. A spectrophotometer and a scanning electron microscope were used to characterize the materials and nanostructures.
Emerging Challenges of Microactuators for Nanoscale Positioning, Assembly, and Manipulation
Authors: Sahu Bijoyraj , Taylor Curtis R. , Leang Kam K.
Published: June 2010

The development of manufacturing tools and processes capable of precisely positioning and manipulating nanoscale components and materials is still in its embryonic stage. Microactuators are emerging as important tools capable of precisely positioning and manipulating nanoscale components and materials. This paper provides a summary of the state-of-the-art in the design, fabrication, and application of microactuators for nanoscale manufacturing and assembly. Key characteristics and design models of electrothermal and electrostatic microactuators are described and compared. Specific design requirements for their functionality at the nanoscale are discussed. The results demonstrate the limitations of existing microactuator designs and key challenges associated with their design, modeling, and performance characterization for nanoscale positioning, assembly, and manipulation.
Construction and Analysis of Nanoscale Simulative Measuring Model for Scanning Near-Field Optical Microscope
Authors: Lin Zone-Ching , Chou Ming-Ho
Published: June 2010

This study constructs a novel scanning near-field optical microscope (SNOM) fixed-amplitude simulative measuring model. It uses Al, Si, and O atoms to compose the probe tip and sample to construct the atomic model of SNOM simulative measuring model. It also applies Morse potential to calculate the atomic interaction force between tip and sample on the vibration theory of SNOM. This study compares the edge effect of surface profile between the simulated measurement with experimental measurement; it verifies that the nanoscale simulative measuring model for SNOM is reasonable and accurate. After analyzing the edge effect and error about the surface profile of standard sample by the SNOM simulated measurement, it is found that the factor influencing this surface profile appearance is mainly from the tip shapes. The investigation of the error analysis is referential in compensating the error of SNOM measurement and it can be used to further enhance the accuracy of SNOM measurement.
A Statistical Analysis to Control the Growth of Cobalt Ferrite Nanoparticles Synthesized by the Thermodecomposition Method
Authors: Calero-DdelC Victoria L. , Gonzalez Ana M. , Rinaldi Carlos
Published: June 2010

A statistical design of experiments was used to study the effect of reaction temperature and time on the synthesis of cobalt ferrite nanoparticles by the thermodecomposition method. A 24–2 factorial experimental design with two central points was used in which the control variables were the time and temperature of the nucleation and growth stages. Transmission electron microscopy, X-ray diffraction, inductively coupled plasma optical emission spectroscopy, and magnetic measurements were used for particle characterization. Cobalt-substituted ferrite (CoxFe3−xO4) nanoparticles with diameters between 9 nm and 13 nm were obtained by varying the nucleation temperature between 150°C and 250°C, the growth temperature between 300°C and 330°C, and the time in each stage between 60 min and 120 min. Statistical analysis showed that only the temperatures had an influence on the final particle size. The analysis of variance indicates that increase in the nucleation temperature resulted in decreased particle size, whereas the increase in temperature in the growth stage resulted in an increase in particle size. Additionally, statistical analysis showed that the growth temperature had an effect on Fe/Co ratio. An increase in the growth temperature produces a decrease in the Fe/Co ratio. Finally, a statistically significant correlation was found between particle diameter and saturation magnetization at 5 K and 300 K. No correlation was found between diameter and other magnetic properties.
Pulse Breakdown in Sub-20 nm Organic Dielectrics for Nanoscale-Electromachining (nano-EM)
Authors: Virwani Kumar R. , Malshe Ajay P. , Rajurkar Kamlakar P.
Published: June 2010

Nano-electromachining (nano-EM) is a process in which electric fields applied across sub-20 nm tool-workpiece gaps in organic dielectrics (n-decane C10H22 and n-undecane C12H26) are used to produce nanometer size features (8–80 nm) in electrically conductive materials. In order to improve the speed of nano-EM for manufacturing, utilization of pulse breakdown phenomena is studied. Linear behavior of Paschen curves for pulse breakdown demonstrated the predictability of pulse nano-EM process. The discharge current in the machining gap showed exponential decay behavior in the post-breakdown regime with certain delay. This delay in current recovery may present a limit to improving nano-EM production speeds and suggests a need for external pressurized dielectric flow over self-guided diffusion. Other notable effects such as adsorption compression limited dielectric diffusion and the variation in the recovery current with the tool-workpiece gap along with their engineering implications are discussed.
Subpolar Link to the Emergence of the Modern Equatorial Pacific Cold Tongue
Authors: Martínez-Garcia Alfredo , Rosell-Melé Antoni , McClymont Erin L. , Gersonde Rainer , Haug Gerald H.
Published: June 2010

Birth of the Cool

Over the past 4 million years or so, tropical sea surface temperatures have experienced a cooling trend (see the Perspective by

Philander

).

Herbert
et al.

(p.
1530
) analyzed sea surface temperature records of the past 3.5 million years from low-latitude sites spanning the world's major ocean basins in order to determine the timing and magnitude of the cooling that has accompanied the intensification of Northern Hemisphere ice ages since the Pliocene.

Martínez-Garcia
et al.

(p.
1550
) found that the enigmatic eastern equatorial Pacific cold tongue, a feature one might not expect to find in such a warm region receiving so much sunlight, first appeared between 1.8 and 1.2 million years ago. Its appearance was probably in response to a general shrinking of the tropical warm water pool caused by general climate cooling driven by changes in Earth's orbit.
Tropical Ocean Temperatures Over the Past 3.5 Million Years
Authors: Herbert Timothy D. , Peterson Laura Cleaveland , Lawrence Kira T. , Liu Zhonghui
Published: June 2010

Birth of the Cool

Over the past 4 million years or so, tropical sea surface temperatures have experienced a cooling trend (see the Perspective by

Philander

).

Herbert
et al.

(p.
1530
) analyzed sea surface temperature records of the past 3.5 million years from low-latitude sites spanning the world's major ocean basins in order to determine the timing and magnitude of the cooling that has accompanied the intensification of Northern Hemisphere ice ages since the Pliocene.

Martínez-Garcia
et al.

(p.
1550
) found that the enigmatic eastern equatorial Pacific cold tongue, a feature one might not expect to find in such a warm region receiving so much sunlight, first appeared between 1.8 and 1.2 million years ago. Its appearance was probably in response to a general shrinking of the tropical warm water pool caused by general climate cooling driven by changes in Earth's orbit.
Response to Comment on “Deep-Sea Temperature and Ice Volume Changes Across the Pliocene-Pleistocene Climate Transitions”
Authors: Sosdian S. , Rosenthal Y.
Published: June 2010

Yu and Broecker argue that the paleoceanographic interpretation of our 3.2-million-year record of North Atlantic deep-sea temperature hinges on the determination of whether temperature or carbonate saturation is the primary driver of benthic foraminiferal magnesium/calcium ratios from the North Atlantic. Here, we present evidence supporting our argument that bottom-water temperature variability is the primary control on benthic foraminiferal Mg/Ca at our site.