bluuebunny/crossref_metadata_2025 huggingface dataset:
“Firm in principles, flexible in strategy and tactics”
Authors: Do Thuy T
Published: November 2016

Since 1991, Vietnam has adopted a dual strategic position towards China: it sees China as an indispensable economic and security partner and simultaneously it seeks to hedge against China’s possible territorial encroachment by gradually beefing up its military and cautiously forging strategic ties with other powers. The making of Vietnam’s current China policy is predominantly shaped by the interplay of two constants (geography and history) and two variables (China’s policy and changing big power relations). Among these factors, geography and history serve as the basis for understanding Vietnam’s hedging policy vis-a-vis China and explain why thus far Hanoi remains very reluctant to enter an alliance to counter China’s rise. While being firm on its independent policy, Vietnam has become more “flexible in strategy and tactics” in rebalancing itself from China’s orbit towards the West’s as the result of China’s increased assertiveness in the South China Sea disputes.
Acquired von Willebrand Syndrome
Authors: Jones Melissa B. , Ramakrishnan Karthik , Alfares Fahad A. , Endicott Kendal M. , Oldenburg Gary , Berger John T. , Shankar Venkat , Nath Dilip S. , Diab Yaser A.
Published: November 2016

Background:

Acquired von Willebrand syndrome (AvWS) in the setting of congenital heart disease is an under-recognized cause of bleeding in the pediatric cardiac critical care unit.

Methods:

Fourteen patients diagnosed with AvWS admitted to the cardiac intensive care unit at the Children’s National Health System between December 2009 and September 2015 were identified with subsequent chart review and case analysis.

Results:

Of the 14 patients included in this study, 4 patients were on ventricular-assist devices, 6 patients were on extracorporeal membrane oxygenation, and 4 were patients with congenital heart disease not receiving any mechanical circulatory support. All patients identified manifested persistent severe bleeding, despite appropriate management of anticoagulation and blood product administration based on the established protocols. Detailed hemostatic testing including quantitative von Willebrand factor (vWF) multimer analysis revealed decreased high-molecular-weight multimers (HMWMs) and absent ultra-HMWM, consistent with AvWS in all patients. Eight patients received treatment with vWF concentrate, one patient with desmopressin, and five recovered without specific treatment. Bleeding ceased in all but one patient.

Conclusions:

Acquired von Willebrand syndrome is an uncommon but important cause of bleeding in pediatric patients with cardiac disease. A high index of clinical suspicion with knowledge of the characteristic clinical scenario in addition to low levels of vWF multimers is required to manage and diagnose AvWS. Although the optimal management of AvWS in this patient population is unclear, vWF concentrates are available and appear to be efficacious for controlling life-threatening bleeding.
Isolated Subclavian Artery
Authors: Sen Supratim , Mohanty Smrutiranjan , Kulkarni Snehal , Rao Suresh G.
Published: November 2016

Isolation of the subclavian artery is a rare aortic arch anomaly with fewer than 100 cases reported in the literature. Left subclavian artery isolation is seen in 0.8% of right aortic arches, and right subclavian artery isolation is seen four times less frequently. Other intracardiac or arch malformations are usually associated, among which tetralogy of Fallot is commonly described. We describe the presentation, preoperative imaging, surgical strategies, and outcomes of four patients with this rare condition and review the published literature. The embryological basis and interesting pathophysiology are also discussed. Surgical division and reimplantation of the isolated subclavian artery onto the aortic arch or common carotid artery is the treatment of choice, with good immediate and midterm outcomes.
Humanitarian Cardiology and Cardiac Surgery in Sub-Saharan Africa
Authors: Tefera Endale , Nega Berhanu , Yadeta Dejuma , Chanie Yilkal
Published: November 2016

Background:

In recent decades, humanitarian cardiology and cardiac surgery have shifted toward sending short-term surgical and catheter missions to treat patients. Although this model has been shown to be effective in bringing cardiovascular care to the patients’ environment, its effectiveness in creating sustainable service is questioned. This study reports the barriers to contribution of missions to effective skill transfer and possible improvements needed in the future, from the perspective of both the local and overseas teams.

Methods:

We reviewed the mission-based activities in the Children’s Heart Fund Cardiac Center in the past six years. We distributed questionnaires to the local surgeons and the lead surgeons of the overseas teams.

Results:

Twenty-six missions visited the center 57 times. There were 371 operating days and 605 surgical procedures. Of the procedures performed, 498 were open-heart surgeries. Of the operations, 360 were congenital cases and 204 were rheumatic. Six local surgeons and 18 overseas surgeons responded. Both groups agree the current model of collaboration is not optimal for effective skill transfer. The local surgeons suggested deeper involvement of the universities, governmental institutions, defined training goals and time frame, and communication among the overseas teams themselves as remedies in the future. Majority of the overseas surgeons agree that networking and regular communication among the missions themselves are needed. Some reflected that it would be convenient if the local surgeons are trained by one or two frequently visiting surgeons in their early years and later exposed to multiple teams if needed.

Conclusion:

The current model of collaboration has brought cardiac care to patients having cardiac diseases. However, the model appears to be suboptimal for skill transfer. The model needs to be reshaped to achieve this complex goal.
Design and Implementation of a Prospective Adult Congenital Heart Disease Biobank
Authors: Opotowsky Alexander R. , Loukas Brittani , Ellervik Christina , Moko Lilamarie E. , Singh Michael N. , Landzberg Elizabeth I. , Rimm Eric B. , Landzberg Michael J.
Published: November 2016

Background:

Adults with congenital heart disease (ACHD) comprise a growing, increasingly complex population. The Boston Adult Congenital Heart Disease Biobank is a program for the collection and storage of biospecimens to provide a sustainable resource for scientific biomarker investigation in ACHD.

Methods:

We describe a protocol to collect, process, and store biospecimens for ACHD or associated diagnoses developed based on existing literature and consultation with cardiovascular biomarker epidemiologists. The protocol involves collecting urine and ∼48.5 mL of blood. A subset of the blood and urine undergoes immediate clinically relevant testing. The remaining biospecimens are processed soon after collection and stored at −80°C as aliquots of ethylenediaminetetraacetic acid (EDTA) and lithium heparin plasma, serum, red cell and buffy coat pellet, and urine supernatant. Including tubes with diverse anticoagulant and clot accelerator contents will enable flexible downstream use. Demographic and clinical data are entered into a database; data on biospecimen collection, processing, and storage are managed by an enterprise laboratory information management system.

Results:

Since implementation in 2012, we have enrolled more than 650 unique participants (aged 18-80 years, 53.3% women); the Biobank contains over 11,000 biospecimen aliquots. The most common primary CHD diagnoses are single ventricle status-post Fontan procedure (18.8%), repaired tetralogy of Fallot with pulmonary stenosis or atresia (17.6%), and left-sided obstructive lesions (17.5%).

Conclusions:

We describe the design and implementation of biospecimen collection, handling, and storage protocols with multiple levels of quality assurance. These protocols are feasible and reflect the size and goals of the Boston ACHD Biobank.
Surgical Treatment for Double Outlet Right Ventricle With Pulmonary Outflow Tract Obstruction
Authors: Wu Qingyu , Jin Yongqiang , Li Hongyin , Zhang Mingkui
Published: November 2016

Background:

Double outlet right ventricle (DORV) is a conotruncal anomaly that is a defining element of many types of complex congenital heart disease. Because of a big variety of pathology, there are still some controversies with respect to the definition, classification, and surgical treatment. We report our experience with surgical treatment for DORV (as defined by the “90% rule”) with pulmonary outflow tract obstruction (POTO).

Methods:

From July 2005 to July 2015, 90 patients underwent surgical treatment of DORV with POTO at the First Hospital of Tsinghua University. There were 55 males and 35 females whose age varies from 3 months to 36 years (mean age 7.1 ± 9.0 years old), and body weights ranged from 5 to 63 kg (mean weight 20.4 ± 16.6 kg). Besides DORV, ventricular septal defect, and POTO, this group of patients includes some with additional associated cardiac abnormalities.

Results:

Fourteen patients (15.6%) died. The main cause of death was low cardiac output syndrome.

Conclusions:

The DORV is usually associated with a variety of cardiac abnormalities and POTO is a common defining feature. Acceptable surgical results can be achieved by individualized surgical treatment of most patients. Some patients may require reoperation, and a close follow-up is needed.
Three Dimensional Visualization of Human Cardiac Conduction Tissue in Whole Heart Specimens by High-Resolution Phase-Contrast CT Imaging Using Synchrotron Radiation
Authors: Shinohara Gen , Morita Kiyozo , Hoshino Masato , Ko Yoshihiro , Tsukube Takuro , Kaneko Yukihiro , Morishita Hiroyuki , Oshima Yoshihiro , Matsuhisa Hironori , Iwaki Ryuma , Takahashi Masashi , Matsuyama Takaaki , Hashimoto Kazuhiro , Yagi Naoto
Published: November 2016

Background:

The feasibility of synchrotron radiation-based phase-contrast computed tomography (PCCT) for visualization of the atrioventricular (AV) conduction axis in human whole heart specimens was tested using four postmortem structurally normal newborn hearts obtained at autopsy.

Methods:

A PCCT imaging system at the beamline BL20B2 in a SPring-8 synchrotron radiation facility was used. The PCCT imaging of the conduction system was performed with “virtual” slicing of the three-dimensional reconstructed images. For histological verification, specimens were cut into planes similar to the PCCT images, then cut into 5-μm serial sections and stained with Masson’s trichrome.

Results:

In PCCT images of all four of the whole hearts of newborns, the AV conduction axis was distinguished as a low-density structure, which was serially traceable from the compact node to the penetrating bundle within the central fibrous body, and to the branching bundle into the left and right bundle branches. This was verified by histological serial sectioning.

Conclusion:

This is the first demonstration that visualization of the AV conduction axis within human whole heart specimens is feasible with PCCT.
Osteoporosis
Authors: Randolph Susan A.
Published: November 2016

Occupational and environmental health nurses should educate workers about healthy lifestyle choices such as proper nutrition and exercise to prevent osteoporosis and reduce the risk of fractures.
A Space for Place in Business Communication Research
Authors: Andrews Deborah C.
Published: November 2016

Many corporate leaders believe that the physical environment of the workplace can play a major role in fostering the interdisciplinary collaboration they link to organizational innovation and in creating a brand that attracts and keeps highly talented employees. Their belief aligns with a recent materialist turn in scholarship that addresses the mutual creation of objects and subjects. Taking advantage of ubiquitous communications technology, the open plan design of these new workplaces offers a variety of settings, created more through furnishings than architecture, to support the four modes of 21st-century work: collaborate, socialize, learn, and focus. In this flexible, “mobile” workplace, people and things mutually reconfigure themselves as projects and preferences change. A tension exists, however, between group-oriented communication conducted face-to-face and private, individual thinking. Exploring the fit between the rhetoric of what space can do, especially enhancing collaboration and achieving innovation, and results on the ground, is an inviting, largely untapped, area for business communication research.
Sonographer-Identified Barriers and Facilitators to Prenatal Screening for Congenital Heart Disease
Authors: Pinto Nelangi , Sheng Xiaoming , Keenan Heather T. , Byrne Janice L. B. , Stanton Belva , Kinney Anita Y.
Published: November 2016

Background: Fetal ultrasound screening for congenital heart disease has high detection rates in efficacy studies but not in practice. We investigated sonographers’ perspectives on barriers to screening and their association with intermediate measures of cardiac imaging. Methods: Barriers to fetal heart screening were identified in focus groups with obstetric sonographers. A web-based survey measured reported barriers and sonographers’ ability to interpret fetal heart screening images. Generalized linear random effect models assessed associations between barriers and image interpretation. Results: Four themes were identified: intrinsic barriers (self-efficacy), external barriers (time), informational needs, and provider and patient expectations. Among 224 sonographers surveyed, an average of 77.6% of fetal heart images were interpreted correctly. Perceptions about self-efficacy ( P = .03) and ease of performing imaging ( P = .01) were associated with accuracy of image interpretation. Conclusions: Several sonographer-identified barriers associated with image interpretation may be novel targets for improving prenatal detection of congenital heart disease.
A Descent Lemma Beyond Lipschitz Gradient Continuity: First-Order Methods Revisited and Applications
Authors: Bauschke Heinz H. , Bolte Jérôme , Teboulle Marc
Published: November 2016

The proximal gradient and its variants is one of the most attractive first-order algorithm for minimizing the sum of two convex functions, with one being nonsmooth. However, it requires the differentiable part of the objective to have a Lipschitz continuous gradient, thus precluding its use in many applications. In this paper we introduce a framework which allows to circumvent the intricate question of Lipschitz continuity of gradients by using an elegant and easy to check convexity condition which captures the geometry of the constraints. This condition translates into a new descent lemma which in turn leads to a natural derivation of the proximal-gradient scheme with Bregman distances. We then identify a new notion of asymmetry measure for Bregman distances, which is central in determining the relevant step-size. These novelties allow to prove a global sublinear rate of convergence, and as a by-product, global pointwise convergence is obtained. This provides a new path to a broad spectrum of problems arising in key applications which were, until now, considered as out of reach via proximal gradient methods. We illustrate this potential by showing how our results can be applied to build new and simple schemes for Poisson inverse problems.
Support for mentors—an exploration of the issues
Authors: Clark Liz , Casey Debbie
Published: November 2016

Nursing and midwifery mentors are fundamental to the process of ensuring future practitioners are adequately prepared and supported during the practice element of their degrees. However, there is evidence to suggest that the infrastructure and support for the mentoring role is not always adequate. This article provides a review of some of the issues including the emotional labour associated with supporting pre-registration students, difficulties in accessing protected learning time for mentoring, and lack of supportive networks for mentors to develop within the role. The authors make recommendations on what is required to ensure that the mentor role is better acknowledged, supported and resourced.
Health psychology: supporting the self-management of long-term conditions
Authors: Barley Elizabeth , Lawson Victoria
Published: November 2016

This article considers how knowledge of health psychology can help nurses support patients in managing their long-term conditions. The concept of ‘self-management’ is defined and the need for self-efficacy—the patient's confidence in their ability to manage—and social support is highlighted. Patients' ‘illness perceptions’, or beliefs about the nature of their condition, also have an impact on their self-management. This is discussed in particular relation to adherence to treatment. A distinction is made between intentional and non-intentional non-adherence. Understanding of the many factors, other than lack of knowledge, that influence self-management success will help nurses and patients work together to develop an effective self-management plan.
Supporting patients with eczema—introducing the TalkingEczema tool
Authors: Onselen Julie Van
Published: November 2016

Julie Van Onselen discusses the TalkingEczema tool that empowers patients with eczema who self-care, and their clinicians, to improve the treatment and management of a condition that affects one in ten adults
Principles for discharging patients from acute care: a scoping review of policy
Authors: Lees-Deutsch Liz , Yorke Janelle , Caress Ann-Louise
Published: November 2016

Background:

Acute medicine units (AMUs) are part of acute hospital care, where length of patient stay is short and turnover is high. Expediting patient discharge safely is a major function of AMUs, which need up-to-date bespoke guidance.

Aim:

To carry out a scoping review of UK discharge policy to critically consider, compare and contrast the relevant discharge policies and guidance that underpin the assessment of acute patient discharge.

Objectives:

To inform the production of bespoke patient discharge guidance for AMUs.

Design and stages:

Identify the review questions; identify relevant studies; select the studies; chart the data; collate, summarise and report the results.

Findings:

28 patient discharge policy guidelines were identified that had no specific guidance for patient discharge from AMUs. New bespoke principles for AMUs were created through a pragmatic interpretation of current relevant policies.

Conclusion:

There is a gap in specific patient discharge guidance for AMUs. New guidance should contribute in practice to improve patient discharge.
Promoting resilience in nursing
Authors: Foster Sam
Published: November 2016

Sam Foster, Chief Nurse at Heart of England NHS Foundation Trust, considers recent research into role stressors and coping strategies for executive nurse directors
Understanding teenage obesity
Authors: Cremonesini Louise , Oben Jude A
Published: November 2016

A look at the factors that can influence unhealthy weight. By Lousie Cremonesini and Jude A Oben
Eczematous conditions in older patients
Authors: Lawton Sandra
Published: November 2016

Dry skin is a common problem associated with ageing and eczematous conditions are commonly seen in practice. Effective use of emollients improves the skin barrier and reduces the potential for inflammation and dry skin. Non-medical prescribers have the potential to support older people in a variety of care settings to ensure they are able to care for their skin, use products that will not exacerbate the condition and treat the eczema accordingly with emollients and topical corticosteroids. This will improve the quality of life and comfort for their patients.
Measuring the effect of femoral malrotation on knee joint biomechanics for total knee arthroplasty using computational simulation
Authors: Kang K-T. , Koh Y-G. , Son J. , Kwon O-R. , Baek C. , Jung S. H. , Park K. K.
Published: November 2016

Objectives

Malrotation of the femoral component can result in post-operative complications in total knee arthroplasty (TKA), including patellar maltracking. Therefore, we used computational simulation to investigate the influence of femoral malrotation on contact stresses on the polyethylene (PE) insert and on the patellar button as well as on the forces on the collateral ligaments.

Materials and Methods

Validated finite element (FE) models, for internal and external malrotations from 0° to 10° with regard to the neutral position, were developed to evaluate the effect of malrotation on the femoral component in TKA. Femoral malrotation in TKA on the knee joint was simulated in walking stance-phase gait and squat loading conditions.

Results

Contact stress on the medial side of the PE insert increased with internal femoral malrotation and decreased with external femoral malrotation in both stance-phase gait and squat loading conditions. There was an opposite trend in the lateral side of the PE insert case. Contact stress on the patellar button increased with internal femoral malrotation and decreased with external femoral malrotation in both stance-phase gait and squat loading conditions. In particular, contact stress on the patellar button increased by 98% with internal malrotation of 10° in the squat loading condition. The force on the medial collateral ligament (MCL) and the lateral collateral ligament (LCL) increased with internal and external femoral malrotations, respectively.

Conclusions

These findings provide support for orthopaedic surgeons to determine a more accurate femoral component alignment in order to reduce post-operative PE problems. Cite this article: K-T. Kang, Y-G. Koh, J. Son, O-R. Kwon, C. Baek, S. H. Jung, K. K. Park. Measuring the effect of femoral malrotation on knee joint biomechanics for total knee arthroplasty using computational simulation. Bone Joint Res 2016;5:552–559. DOI: 10.1302/2046-3758.511.BJR-2016-0107.R1.
Rule-In and Rule-Out of Myocardial Infarction Using Cardiac Troponin and Glycemic Biomarkers in Patients with Symptoms Suggestive of Acute Coronary Syndrome
Authors: Shortt Colleen , Ma Jinhui , Clayton Natasha , Sherbino Jonathan , Whitlock Richard , Pare Guillaume , Hill Stephen A , McQueen Matthew , Mehta Shamir R , Devereaux P J , Worster Andrew , Kavsak Peter A
Published: November 2016

BACKGROUND

Early rule-in/rule-out of myocardial infarction (MI) in patients presenting to the emergency department (ED) is important for patient care and resource allocation. Given that dysglycemia is a strong risk factor for MI, we sought to explore and compare different combinations of cardiac troponin (cTn) cutoffs with glycemic markers for the early rule-in/rule-out of MI.

METHODS

We included ED patients (n = 1137) with symptoms suggestive of acute coronary syndrome (ACS) who had cTnI, high-sensitivity cTnI (hs-cTnI), hs-cTnT, glucose, and hemoglobin A1c (Hb A1c) measurements. We derived rule-in/rule-out algorithms using different combinations of ROC-derived and literature cutoffs for rule-in and rule-out of MI within 7 days after presentation. These algorithms were then tested for MI/cardiovascular death and ACS/cardiovascular death at 7 days. ROC curves, sensitivity, specificity, likelihood ratios, positive and negative predictive values (PPV and NPV), and CIs were determined for various biomarker combinations.

RESULTS

MI was diagnosed in 133 patients (11.7%; 95% CI, 9.8–13.8). The algorithms that included cTn and glucose produced the greatest number of patients ruled out/ruled in for MI and yielded sensitivity ≥99%, NPV ≥99.5%, specificity ≥99%, and PPV ≥80%. This diagnostic performance was maintained for MI/cardiovascular death but not for ACS/cardiovascular death. The addition of hemoglobin A1c (Hb A1c) (≥6.5%) to these algorithms did not change these estimates; however, 50 patients with previously unknown diabetes may have been identified if Hb A1c was measured.

CONCLUSIONS

Algorithms incorporating glucose with cTn may lead to an earlier MI diagnosis and rule-out for MI/cardiovascular death. Addition of Hb A1c into these algorithms allows for identification of diabetes. Future studies extending these findings are needed for ACS/cardiovascular death. ClinicalTrials.gov identifier: NCT01994577
Hubungan Mengikuti Kelompok Bermain dan Perkembangan Anak
Authors: Maimon Elsa , Ismail Djauhar , Sitaresmi Mei Neni
Published: November 2016

Latar belakang. Pendidikan anak usia dini merupakan salah satu bentuk stimuli yang akan memacu perkembangan anak agar berjalan secara optimal sesuai usianya. Salah satu bentuk pendidikan yang banyak ditawarkan saat ini adalah kelompok bermain. Sebagian orang tua ragu tentang manfaat mengikuti kelompok bermain untuk perkembangan anak. Sebuah penelitian kohort menyebutkan bahwa pendidikan usia dini memberikan kehidupan sosial yang lebih baik, tetapi penelitian tersebut tidak mengevaluasi pertkembangan anak.Tujuan. Mengetahui hubungan mengikuti kelompok bermain dengan pencapaian perkembangan anak.Metode. Penelitian dilakukan di kota Yogyakarta secara cross sectional dengan mengambil subyek murid Taman Kanak-kanak yang baru satu bulan bersekolah dan dilakukan penilaian perkembangan dengan metode Denver II. Analisis statistik dilakukan dengan uji X².Hasil. Seratus tujuh puluh dua anak menjalani pemeriksaan perkembangan dan melengkapi data penelitian. Pencapaian perkembangan anak lebih baik pada kelompok anak yang mengikuti kelompok bermain dibandingkan dengan anak yang tidak mengikuti kelompok bermain (p=0,003). Mengikuti kelompok bermain memberikan kontribusi pada perkembangan anak (OR 3,2; IK 95%: 1,558-6,774, p=0,002).Kesimpulan. Mengikuti kelompok bermain berhubungan dengan pencapaian perkembangan anak dan bermanfaat untuk perkembangan anak.
Studi Observasional Pasca-Pemasaran Formula Isolat Protein Kedelai pada Bayi dengan Gejala Sugestif Alergi Terhadap Protein Susu Sapi
Authors: Munasir Zakiudin , Muktiarti Dina , Endaryanto Anang , Kumarawati Ketut Dewi , Setiabudiawan Budi , Sumadiono Sumadiono , Hudyono Johannes , Louisa Melva , Setiawati Arini
Published: November 2016

Latar belakang. Fomula berbasis isolat protein kedelai banyak digunakan untuk anak-anak dengan alergi susu sapi di Indonesia. Namun, diperlukan penelitian untuk mendapatkan gambaran penerimaan orangtua dan toleransi saluran cerna pada penggunaan formula isolat protein kedelai.Tujuan. Pertama, menentukan penerimaan orangtua terhadap pemberian suatu isolat protein kedelai pada bayi yang diduga mengalami alergi terhadap protein susu sapi. Kedua, mengetahui toleransi saluran cerna pada pemberian susu formula tersebut.Metode. Suatu studi pasca-pemasaran, prospektif, multisenter yang dilakukan di Jakarta, Bandung, Surabaya, Yogyakarta, Solo, dan Denpasar sejak September 2011 sampai April 2012. Subyek berusia antara 6 bulan hingga 1 tahun dengan gejala dugaan alergi terhadap protein susu sapi yang diberikan formula isolat protein kedelai dan diamati selama 4 minggu. Luaran yang diharapkan adalah penerimaan orangtua terhadap pemberian formula isolat protein kedelai dan toleransi saluran cerna terhadap pemberian isolat protein kedelai.Hasil. Diteliti 534 subyek yang dapat dianalisis selama periode penelitian. Mayoritas orangtua (84%) merasa puas dengan formula isolat protein kedelai, 83% orangtua berencana untuk melanjutkan pemberian susu formula karena berkurang (31,5%) dan hilangnya gejala yang diduga akibat alergi susu sapi (32,4%). Gejala klinis yang diduga akibat alergi terhadap protein susu sapi menurun pada setiap kunjungan berikutnya. Tidak ada efek samping serius yang dilaporkan selama periode penelitian.Kesimpulan. Penelitian ini menemukan tingkat penerimaan orangtua dan toleransi saluran cerna yang baik terhadap pemberian formula isolat protein kedelai kepada bayi dengan gejala sugestif alergi terhadap protein susu sapi. Formula isolat protein kedelai cukup aman dijadikan sebagai formula alternatif pengganti pada anak dengan alergi susu sapi.
Social media and their use in learning: A comparative analysis between Australia and Malaysia from the learners’ perspectives
Authors: Balakrishnan Vimala , Teoh Kung Keat , Pourshafie Tahereh , Liew Teik Kooi
Published: November 2016

This study is an investigation into factors that encourage and/or inhibit the use of social media in the academic learning process between Australian and Malaysian students at higher learning institutions. Push-pull-mooring theory was used as a guide, resulting in seven independent variables (convenience, social influence, academic reasons, ease of use, social networking, barriers, and e-learning perception), and one dependent variable (teaching and learning benefit). The study included a survey of 524 respondents (NAustralia = 214; NMalaysia = 310). Path modeling analysis revealed three common factors between students from both countries: academic reasons, barriers, and social networking. However Malaysian students revealed a significant greater emphasis on academic reasons and barriers compared to their Australian counterparts. No significant difference was noted for social networking, suggesting that the use of social media as a means to maintain social interaction is popular regardless of cultural differences. Alternatively, significant effects were observed for convenience and e-learning perception among Australian students, while ease of use was found to have significant impact on Malaysian students. The findings suggest that cultural differences and the education system will impact the use of social media as an online learning tool.
Using cultural historical activity theory to examine how teachers seek and share knowledge in a peer-to-peer professional development network
Authors: Trust Torrey
Published: November 2016

Many researchers have found that the main reason teachers participate in peer-to-peer professional development networks (PDNs) is to seek and share professional knowledge. Yet, the majority of studies about PDNs focus on how and why teachers participate in these virtual spaces rather than how teachers find and distribute knowledge. Each PDN has its own unique rules, tools, community members, and culture that shape how knowledge is created, organised, curated, and shared. Without understanding the factors that shape how and why knowledge is shared in a PDN, teachers may not be able to access the knowledge they need to grow their practice. This study was designed to examine teachers’ knowledge seeking and sharing actions in the Edmodo Math Subject Community, a popular PDN. Cultural historical activity theory was used as a framework for examining the socially constructed actions of seeking and sharing knowledge in a PDN. The findings suggest that seeking and sharing knowledge is a complex, dynamically evolving process that is shaped by the technical (e.g., tools) and social (e.g., community members, rules, roles) aspects of the PDN. Implications and ideas for further research are discussed.
Investigating the effect of learning styles in a blended e-learning system: An extension of the technology acceptance model (TAM)
Authors: Al-Azawei Ahmed , Parslow Patrick , Lundqvist Karsten
Published: November 2016

This study assesses learner perceptions of a blended e-learning system (BELS) and the feasibility of accommodating educational hypermedia systems (EHSs) according to learning styles using a modified version of the technology acceptance model (TAM). Recently, Moodle has been adopted by an Iraqi university alongside face-to-face (F2F) classrooms to provide flexible learning and improve understanding. Based on TAM, individual differences and perceptions were explored in relationships between learner satisfaction and technology adoption. The model was extended to include e-learning self-efficacy, perceived satisfaction, and learning styles. Although other variables can be integrated, the proposed framework is to investigate the effect of learning styles in predicting satisfaction and BELS acceptance. A total of 210 undergraduate students voluntarily took part in the research. Data was gathered using a survey instrument and the Index of Learning Styles (ILS) Questionnaire. Partial least squares structural equation modelling (PLS-SEM) technique was used to examine the path associated between dependent and independent constructs. Unlike prior TAM literature, this research highlights the integration of perceived satisfaction and technology acceptance in accordance with psychological traits and learner beliefs. Overall, the model achieved an acceptable fit and successfully integrated intention to use (ITU) and perceived satisfaction (PS). However, psychological differences did not indicate positive impacts on learner satisfaction and e-learning adoption.
Evaluating the Impact of a HIV Low-Risk Express Care Task-Shifting Program: A Case Study of the Targeted Learning Roadmap
Authors: Tran Linh , Yiannoutsos Constantin T. , Musick Beverly S. , Wools-Kaloustian Kara K. , Siika Abraham , Kimaiyo Sylvester , van der Laan Mark J. , Petersen Maya
Published: November 2016

In conducting studies on an exposure of interest, a systematic roadmap should be applied for translating causal questions into statistical analyses and interpreting the results. In this paper we describe an application of one such roadmap applied to estimating the joint effect of both time to availability of a nurse-based triage system (low risk express care (LREC)) and individual enrollment in the program among HIV patients in East Africa. Our study population is comprised of 16,513 subjects found eligible for this task-shifting program within 15 clinics in Kenya between 2006 and 2009, with each clinic starting the LREC program between 2007 and 2008. After discretizing follow-up into 90-day time intervals, we targeted the population mean counterfactual outcome (i. e. counterfactual probability of either dying or being lost to follow up) at up to 450 days after initial LREC eligibility under three fixed treatment interventions. These were (i) under no program availability during the entire follow-up, (ii) under immediate program availability at initial eligibility, but non-enrollment during the entire follow-up, and (iii) under immediate program availability and enrollment at initial eligibility. We further estimated the controlled direct effect of immediate program availability compared to no program availability, under a hypothetical intervention to prevent individual enrollment in the program. Targeted minimum loss-based estimation was used to estimate the mean outcome, while Super Learning was implemented to estimate the required nuisance parameters. Analyses were conducted with the ltmle R package; analysis code is available at an online repository as an R package. Results showed that at 450 days, the probability of in-care survival for subjects with immediate availability and enrollment was 0.93 (95 % CI: 0.91, 0.95) and 0.87 (95 % CI: 0.86, 0.87) for subjects with immediate availability never enrolling. For subjects without LREC availability, it was 0.91 (95 % CI: 0.90, 0.92). Immediate program availability without individual enrollment, compared to no program availability, was estimated to slightly albeit significantly decrease survival by 4 % (95 % CI 0.03,0.06, p < 0.01). Immediately availability and enrollment resulted in a 7 % higher in-care survival compared to immediate availability with non-enrollment after 450 days (95 % CI –0.08,–0.05, p < 0.01). The results are consistent with a fairly small impact of both availability and enrollment in the LREC program on in-care survival.
Effect of corrective feedback for learning verb second
Authors: Penning de Vries Bart , Cucchiarini Catia , Bodnar Stephen , Strik Helmer , van Hout Roeland
Published: November 2016

This paper presents a detailed study on the role of corrective feedback (CF) in the development of second language (L2) oral proficiency. Learners practiced speaking with a computer-assisted language learning (CALL) system that employs automatic speech recognition (ASR) technology to provide CF. The system tracks learner behaviour by logging the system-user interactions. Two language learning conditions are compared. In the CF condition learners received immediate, automatic CF on the grammaticality of their spoken output. In theOCF condition, learners practiced speaking with the option to self-correct. The target structure under investigation is Dutch verb second (V2) in the main clause. The results show that learner proficiency improved in both conditions. The CF condition shows an additional benefit for learning that is related to the learner’s initial knowledge of the target structure (which we call V2 proficiency). Learners at a lower V2 proficiency level benefitted more from practice with CF than learners in the NOCF condition. Learner evaluations are in line with these results: both the CF and the NOCF groups positively evaluated practice with the system, but the CF condition was preferred by learners starting at a lower V2 proficiency level. For more information on these outcome measures, we investigated the learners’ behaviour during practice. The two groups were found to receive equal amounts of input, but learners in the CF condition produced more (grammatically correct) output during treatment. We found that the CF group repaired their errors in fewer attempts as they progressed through practice. Learners in the NOCF condition generally did not (attempt to) repair their errors. However, the learners answered correctly more often as they progressed in the training. The log data, therefore, shows learning of the target structure in both conditions. We discuss these results and how learning outcome is related to learner behaviour.
A recursive-operational approach with applications to linear differential systems
Authors: Bengochea Gabriel , Ortigueira Manuel
Published: November 2016

In this paper, an operational method for solving linear and nonlinear systems described by ordinary differential equations is presented. The construction is based on the generalized derivative in the sense of distribution theory. The approach allows the response computation without needing the use of any integral transform as in the Mikusiński operational calculus. A general description of the algorithm is done and some illustrating examples are presented. The algorithm is recursive allowing to add and remove any pole or zero contribution. The extension to nonlinear systems is done by means of the Adomian polynomials.
Neurotransmitter Release Can Be Stabilized by a Mechanism That Prevents Voltage Changes Near the End of Action Potentials from Affecting Calcium Currents
Authors: Clarke Stephen G. , Scarnati Matthew S. , Paradiso Kenneth G.
Published: November 2016

At chemical synapses, presynaptic action potentials (APs) activate voltage-gated calcium channels, allowing calcium to enter and trigger neurotransmitter release. The duration, peak amplitude, and shape of the AP falling phase alter calcium entry, which can affect neurotransmitter release significantly. In many neurons, APs do not immediately return to the resting potential, but instead exhibit a period of depolarization or hyperpolarization referred to as an afterpotential. We hypothesized that presynaptic afterpotentials should alter neurotransmitter release by affecting the electrical driving force for calcium entry and calcium channel gating. In support of this, presynaptic calcium entry is affected by afterpotentials after standard instant voltage jumps. Here, we used the mouse calyx of Held synapse, which allows simultaneous presynaptic and postsynaptic patch-clamp recording, to show that the postsynaptic response is affected significantly by presynaptic afterpotentials after voltage jumps. We therefore tested the effects of presynaptic afterpotentials using simultaneous presynaptic and postsynaptic recordings and AP waveforms or real APs. Surprisingly, presynaptic afterpotentials after AP stimuli did not alter calcium channel responses or neurotransmitter release appreciably. We show that the AP repolarization time course causes afterpotential-induced changes in calcium driving force and changes in calcium channel gating to effectively cancel each other out. This mechanism, in which electrical driving force is balanced by channel gating, prevents changes in calcium influx from occurring at the end of the AP and therefore acts to stabilize synaptic transmission. In addition, this mechanism can act to stabilize neurotransmitter release when the presynaptic resting potential changes.

SIGNIFICANCE STATEMENTThe shape of presynaptic action potentials (APs), particularly the falling phase, affects calcium entry and small changes in calcium influx can produce large changes in postsynaptic responses. We hypothesized that afterpotentials, which often follow APs, affect calcium entry and neurotransmitter release. We tested this in calyx of Held nerve terminals, which allow simultaneous recording of presynaptic calcium currents and postsynaptic responses. Surprisingly, presynaptic afterpotentials did not alter calcium current or neurotransmitter release. We show that the AP falling phase causes afterpotential-induced changes in electrical driving force and calcium channel gating to cancel each other out. This mechanism regulates calcium entry at the end of APs and therefore stabilizes synaptic transmission. This also stabilizes responses when the presynaptic resting potential changes.
Local and Use-Dependent Effects of β-Amyloid Oligomers on NMDA Receptor Function Revealed by Optical Quantal Analysis
Authors: Sinnen Brooke L. , Bowen Aaron B. , Gibson Emily S. , Kennedy Matthew J.
Published: November 2016

Beta amyloid (Aβ) triggers the elimination of excitatory synaptic connections in the CNS, an early manifestation of Alzheimer's disease. Oligomeric assemblies of Aβ peptide associate with excitatory synapses resulting in synapse elimination through a process that requires NMDA-type glutamate receptor activation. Whether Aβ affects synaptic NMDA receptor (NMDAR) function directly and acts locally at synapses to which it has bound and whether synaptic activity influences Aβ synaptic binding and synaptotoxicity have remained fundamental questions. Here, we used subcellular Ca2+imaging in rat hippocampal neurons to visualize NMDAR function at individual synapses before and after Aβ application. Aβ triggered a robust impairment of NMDAR Ca2+entry at most, but not all, synapses. NMDAR function was more severely impaired at highly active synapses and synapses with bound Aβ, but activity was not required for Aβ synapse binding. Blocking NMDARs during Aβ exposure prevented Aβ-mediated impairment. Finally, Aβ impaired NMDAR Ca2+entry at doses much lower than those required for NMDAR internalization, revealing a novel, potent mode of NMDAR regulation by Aβ.

SIGNIFICANCE STATEMENTAmyloid β (Aβ) is strongly implicated in Alzheimer's disease. Aβ triggers the elimination of excitatory synapses through a mechanism that requires NMDA receptors (NMDARs). However, little is known about how or whether Aβ influences synaptic NMDAR function. We used an imaging-based assay to investigate the relationship among Aβ binding, activity, and NMDAR function at individual synapses. Aβ triggered a robust impairment of NMDAR Ca2+entry at most, but not all, synapses. NMDAR function was more severely impaired at highly active synapses and synapses with bound Aβ. Blocking NMDARs during Aβ exposure prevented Aβ-mediated impairment. Together, our experiments reveal a novel use-dependent, potent, and local mode of Aβ-mediated NMDAR impairment.
Homeostasis Meets Motivation in the Battle to Control Food Intake
Authors: Ferrario Carrie R. , Labouèbe Gwenaël , Liu Shuai , Nieh Edward H. , Routh Vanessa H. , Xu Shengjin , O'Connor Eoin C.
Published: November 2016

Signals of energy homeostasis interact closely with neural circuits of motivation to control food intake. An emerging hypothesis is that the transition to maladaptive feeding behavior seen in eating disorders or obesity may arise from dysregulation of these interactions. Focusing on key brain regions involved in the control of food intake (ventral tegmental area, striatum, hypothalamus, and thalamus), we describe how activity of specific cell types embedded within these regions can influence distinct components of motivated feeding behavior. We review how signals of energy homeostasis interact with these regions to influence motivated behavioral output and present evidence that experience-dependent neural adaptations in key feeding circuits may represent cellular correlates of impaired food intake control. Future research into mechanisms that restore the balance of control between signals of homeostasis and motivated feeding behavior may inspire new treatment options for eating disorders and obesity.
Neural Stem Cells to Cerebral Cortex: Emerging Mechanisms Regulating Progenitor Behavior and Productivity
Authors: Dwyer Noelle D. , Chen Bin , Chou Shen-Ju , Hippenmeyer Simon , Nguyen Laurent , Ghashghaei H. Troy
Published: November 2016

This review accompanies a 2016 SFN mini-symposium presenting examples of current studies that address a central question: How do neural stem cells (NSCs) divide in different ways to produce heterogeneous daughter types at the right time and in proper numbers to build a cerebral cortex with the appropriate size and structure? We will focus on four aspects of corticogenesis: cytokinesis events that follow apical mitoses of NSCs; coordinating abscission with delamination from the apical membrane; timing of neurogenesis and its indirect regulation through emergence of intermediate progenitors; and capacity of single NSCs to generate the correct number and laminar fate of cortical neurons. Defects in these mechanisms can cause microcephaly and other brain malformations, and understanding them is critical to designing diagnostic tools and preventive and corrective therapies.
Synaptic Actin Dysregulation, a Convergent Mechanism of Mental Disorders?
Authors: Yan Zhen , Kim Eunjoon , Datta Dibyadeep , Lewis David A. , Soderling Scott H.
Published: November 2016

Actin polymerization governs activity-dependent modulation of excitatory synapses, including their morphology and functionality. It is clear from human genetics that neuropsychiatric and neurodevelopmental disturbances are multigenetic in nature, highlighting the need to better understand the critical neural pathways associated with these disorders and how they are altered by genetic risk alleles. One such signaling pathway that is heavily implicated by candidate genes for psychiatric and neurodevelopmental disorders are regulators of signaling to the actin cytoskeleton, suggesting that its disruption and the ensuring abnormalities of spine structures and postsynaptic complexes is a commonly affected pathway in brain disorders. This review will discuss recent experimental findings that strongly support genetic evidence linking the synaptic cytoskeleton to mental disorders, such as schizophrenia and autism spectrum disorders.
Reading Fiction in Biology Class to Enhance Scientific Literacy
Authors: Boswell Helen C. , Seegmiller Tasha
Published: November 2016

Students in the United States struggle with literacy skills, a problem that extends into their undergraduate education and beyond. Particularly in the sciences, reading assignments are usually singularly academic in nature and do not impart the importance of creativity and innovation. We propose a curriculum strategy and lesson plan that employs a “reading across the curriculum” approach to enhance literacy skills in biology students while simultaneously encouraging scientific discourse and creativity.
Clarifying Confusing Science Rules, Vocabulary & Diagrams
Authors: Cook Kristin L. , Bush Sarah B. , Karp Karen
Published: November 2016

While a wealth of research exists examining elementary teachers' and students' alternative conceptions about science and offering recommendations for teacher preparation to include an emphasis on supporting conceptual change, this article presents a useful compilation that serves as a go-to resource on some of the most common oversimplified rules, incomplete or misleading vocabulary, and confusing diagrams promulgated in science teaching that could lead to enduring student misconceptions.