bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of floating-gate memory device with thiolate-protected gold and gold-palladium nanoclusters
Authors: Yokoyama Takaho , Hirata Naoyuki , Tsunoyama Hironori , Negishi Yuichi , Nakajima Atsushi
Published: June 2018

The floating-gate memory characteristics of thiolate-protected gold (Au:SR) and palladium doped Au (AuPd:SR) nanoclusters, Au25(SR)18, Au24Pd(SR)18, and Au38(SR)24 (R = C12H25), were investigated by capacitance-voltage (C–V) measurements in vacuum. Monolayer films of Au:SR nanoclusters were formed as floating-gate memory layers on p-type Si substrates by the Langmuir-Schaefer method with surface pressure − area (π-A) isotherm measurements. A fluoropolymer (CYTOP, ∼15 nm thick) was spin-coated on top to form a hydrophobic insulating layer. Using an Au pad (∼40 nm thick) as the gate electrode, C–V measurements exhibit clockwise hysteresis curves originating from the Au:SR and AuPd:SR nanoclusters against the reference measured in each sample, and the hysteresis widths were dependent on the composition and sizes of the Au:SR nanoclusters. The positive and negative voltage shifts in the hysteresis can be explained in terms of electronic structures in Au:SR and AuPd:SR-based devices.
Invited Article: Mitigation of dynamical instabilities in laser arrays via non-Hermitian coupling
Authors: Longhi S. , Feng L.
Published: June 2018

Arrays of coupled semiconductor lasers are systems possessing complex dynamical behavior and are of major interest in photonics and laser science. Dynamical instabilities, arising from supermode competition and slow carrier dynamics, are known to prevent stable phase locking in a wide range of parameter space, requiring special methods to realize stable laser operation. Inspired by recent concepts of parity-time (PT) and non-Hermitian photonics, in this work, we consider non-Hermitian coupling engineering in laser arrays in a ring geometry and show, both analytically and numerically, that non-Hermitian coupling can help to mitigate the onset of dynamical laser instabilities. In particular, we consider in detail two kinds of nearest-neighbor non-Hermitian couplings: symmetric but complex mode coupling (type-I non-Hermitian coupling) and asymmetric mode coupling (type-II non-Hermitian coupling). Suppression of dynamical instabilities can be realized in both coupling schemes, resulting in stable phase-locking laser emission with the lasers emitting in phase (for type-I coupling) or with π/2 phase gradient (for type-II coupling), resulting in a vortex far-field beam. In type-II non-Hermitian coupling, chirality induced by asymmetric mode coupling enables laser phase locking even in the presence of moderate disorder in the resonance frequencies of the lasers.
Statistics of strain rates and surface density function in a flame-resolved high-fidelity simulation of a turbulent premixed bluff body burner
Authors: Sandeep Anurag , Proch Fabian , Kempf Andreas M. , Chakraborty Nilanjan
Published: June 2018

The statistical behavior of the surface density function (SDF, the magnitude of the reaction progress variable gradient) and the strain rates, which govern the evolution of the SDF, have been analyzed using a three-dimensional flame-resolved simulation database of a turbulent lean premixed methane-air flame in a bluff-body configuration. It has been found that the turbulence intensity increases with the distance from the burner, changing the flame curvature distribution and increasing the probability of the negative curvature in the downstream direction. The curvature dependences of dilatation rate ∇⋅u→ and displacement speed Sd give rise to variations of these quantities in the axial direction. These variations affect the nature of the alignment between the progress variable gradient and the local principal strain rates, which in turn affects the mean flame normal strain rate, which assumes positive values close to the burner but increasingly becomes negative as the effect of turbulence increases with the axial distance from the burner exit. The axial distance dependences of the curvature and displacement speed also induce a considerable variation in the mean value of the curvature stretch. The axial distance dependences of the dilatation rate and flame normal strain rate govern the behavior of the flame tangential strain rate, and its mean value increases in the downstream direction. The current analysis indicates that the statistical behaviors of different strain rates and displacement speed and their curvature dependences need to be included in the modeling of flame surface density and scalar dissipation rate in order to accurately capture their local behaviors.
Solar irradiance forecasting and energy optimization for achieving nearly net zero energy building
Authors: Naveen Chakkaravarthy A. , Subathra M. S. P. , Jerin Pradeep P. , Manoj Kumar Nallapaneni
Published: June 2018

Solar energy and the concept of passive solar architecture are being increased in several areas to attain the net-zero energy concept. This paved the way for an increase in the need of solar irradiance forecasting for both solar PV applications and Passive Solar Architectural buildings. First, solar irradiance forecasting was done with 131 400 data sets (1-h data for 15 years) which was split into monthly mean for every year. This model was evaluated by forecasting the post-consecutive years one by one with the pre-consecutive years which includes the pre-forecasted years. This model was shown to have RMSE values of 11% to 24% for various seasonal forecasting using the Random Forest Algorithm in WEKA, which gave the annual irradiance results nearer to the PV Sol energy forecasting results. The R-value was in the range of 0.8 to 0.9 for various seasons which is good. Building Energy Optimization was carried out using BEopt 2.8 software designed by NREL. The chosen building was set to the standard parameters in India, and then, the optimization was done with various customized parameters and systems available in India to reduce the energy consumption from 192.2 MMBtu/yr to 109.1 MMBtu/yr with a 7 kW Solar PV System to attain the net-zero energy concept.
Analysis of solid particles falling down and interacting in a channel with sedimentation using fictitious boundary method
Authors: Usman K. , Walayat K. , Mahmood R. , Kousar N.
Published: June 2018

We have examined the behavior of solid particles in particulate flows. The interaction of particles with each other and with the fluid is analyzed. Solid particles can move freely through a fixed computational mesh using an Eulerian approach. Fictitious boundary method (FBM) is used for treating the interaction between particles and the fluid. Hydrodynamic forces acting on the particle’s surface are calculated using an explicit volume integral approach. A collision model proposed by Glowinski, Singh, Joseph and coauthors is used to handle particle-wall and particle-particle interactions. The particulate flow is computed using multigrid finite element solver FEATFLOW. Numerical experiments are performed considering two particles falling and colliding and sedimentation of many particles while interacting with each other. Results for these experiments are presented and compared with the reference values. Effects of the particle-particle interaction on the motion of the particles and on the physical behavior of the fluid-particle system has been analyzed.
Foundations play a supporting role in basic science
Authors: Kramer David
Published: June 2018

Philanthropic efforts on behalf of basic research span a range of modalities, from assistance for individual investigators to the establishment of research institutes.
The discovery of Ovshinsky switching and phase-change memory
Authors: Hoddeson Lillian , Garrett Peter
Published: June 2018

An unusually broad set of experiences helped prepare Stanford Ovshinsky to recognize a phenomenon that forever changed solid-state physics.
Geographic patterns of phenotypic diversity in incipient species of North American blister beetles (Coleoptera: Meloidae) are not determined by species niches, but driven by demography along the speciation process
Authors: Salvador de Jesús-Bonilla Vladimir , García-París Mario , Ibarra-Cerdeña Carlos N. , Zaldívar-Riverón Alejandro
Published: June 2018

The Epicauta stigmata complex is a group of blister beetles composed of three parapatric or sympatric species that occur in central Mexico to southern USA: E. stigmata, E. uniforma and E. melanochroa. These species are morphologically very similar, and are mainly distinguished by body colour differences. Here we assessed whether phenotypic divergence in coloration patterns define evolutionary units within the complex. We studied the phylogenetic relationships, demographic history and concordances between morphological and ecological traits in the group. The complex apparently had a demographic history of recent population expansion during the last glaciation period 75000 to 9500 years ago. The three species show no reciprocal monophyly, and thus their allospecificity was not confirmed. The current distribution of haplotypes and the genetic divergences in these taxa can be explained by either recent mitochondrial introgression events caused by hybridisation or by incomplete lineage sorting. Colour pattern differences in the complex are not likely a product of local selection acting over a common genetic background. We suggest that phenotypic divergence in colour patterns during an incipient speciation process might be seen as an enhancing factor of cohesion within each of the three evolutionary units.
Exploring professionals' perceptions of the barriers and enablers to young people with physical disabilities accessing sexual and reproductive health services in Australia
Authors: Ride Georgia , Newton Danielle C.
Published: June 2018

Background
There is a lack of research on young people with physical disabilities’ access to sexual and reproductive health (SRH) services in Australia. Research has found that there are attitudinal, physical and communication barriers for people with disability, in general, accessing health services, including SRH services. This paper explores key informant perceptions of the barriers and enablers to young people with physical disabilities accessing SRH services in Australia. Methods: This research used a qualitative approach and involved semi-structured interviews with key informants. Key informants were identified using purposive and snowball sampling, and included health professionals working in SRH services and disability-focussed organisations. Thematic analysis was used to analyse the data. Results: Key informant interviews were carried out with nine health professionals and professionals from disability-focussed organisations. Key themes were: attitudes, role and capacity of health professionals; and additional supports. These three broad areas can either act as barriers or enablers for young people with physical disabilities to access SRH services. This research highlighted that heterosexual and gender bias creates additional barriers for young women with physical disabilities and young people with physical disabilities who identify as lesbian, gay, bisexual, queer, transgender or intersex (LGBQTI). Conclusion: Young people with physical disabilities face barriers accessing SRH services. Additional barriers are faced by young women and LGBQTI young people with physical disabilities. This paper suggests strategies to overcome these barriers.
Casting methods for the production of rotationally symmetric copper bimetals
Authors: Greß Thomas , Mittler T. , Volk W.
Published: June 2018

Multiple-material products are characterised by a complex property profile which is achieved by combining the particular advantages of at least two different materials. Bimetal casting is an energy- and material-efficient technology for the production of multi-metallic objects. This paper describes the development of a semi-continuous casting process for the formation of a rotationally symmetric bimetal with a cohesive bonding character at the interface of a copper–tin alloy (CuSn6) and pure copper (Cu99.5). Initial experiments are conducted by static casting to evaluate the thermal process window. Based on the results of the initial experiments, a vertical semi-continuous compound casting process is developed. A stable cohesive bond between the joining partners is accomplished by forming a solid solution at the interface.

This paper is part of a Thematic Issue on Copper and its Alloys.
Microsatellite and SNAP markers used for evaluating pollen dispersal on Pati tall coconuts and Xenia effect on the production of ‘Kopyor’ fruits
Authors: Larekeng S H , Purwito A , Mattjik N A , Sudarsono S
Published: June 2018

Kopyor coconut is one of the many unique coconut types existed in Indonesia. To overcome the problem of low kopyor fruit yield, it is necessary to study xenia effect on the fruit yield of this coconut. The combination of kopyor coconut and normal coconut population selected at infarmers’ coconut plantations consisted of 33 normal coconut trees, and 9 kopyor coconut trees. All adult trees surrounding the 9 kopyor heterozygous (Kk) palms were evaluated as potential male candidate parents (pollen donors). All samples genotypes were determined using four SNAP markers and six microsatellite marker loci, parentage analysis using CERVUS software version 2.0. Results of the analysis indicate that xenia effect reduced kopyor fruit yields. Kopyor heterozygous (Kk) female parents produced low number of kopyor fruits when they were surrounded by many normal homozygous (KK) pollen donors. Out of 99 harvested progeny arrays from the kopyor heterozygous (Kk) female parents, none exhibited kopyor phenotype. The results also indicate that the pollen dispersal from normal homozygous (KK) donor palms range from 0 m (self pollination) to 54 m (outcrossing). The occurence of outcrossing frequency was at least 95% and the selfing frequency is 5%.
Improving agricultural commodity supply-chain to promote economic activities in rural area
Authors: Padjung R
Published: June 2018

Long supply chain of agricultural commodities has become concern to governments particularly in large countries such as Indonesia as it causes high price disparity between farm-gate and retailer. Policies to overcome such problem are usually by shortening the chain, by which farmers sell the products directly to retailers. Using an action research in AEDEF (Aceh Economic Development Financing Facilities) Program, conducted in the province of Nangro Aceh Darussalam (NAD) Indonesia, the paper shows that shortening the commodity supply chain is not the best solution to such problem, as it causes loss of jobs in the villages. High price disparity between farm-gate and retailer is not necessary brought about by long supply-chain but by the efficiency of the chain instead. Efficiency of the chain can be improved by creating enabling business environment such that every actors and players work in a fair manner. This can be achieved by transparency in price and quality grade. With development achieved in Information and Communication Technology (ICT), having a good and reliable flow of such information is not difficult. In addition to information flow, the availability and quality of infrastructure to support flow of goods from farm-gate to end-user is of reasonably important.
Clinical applications of retinal gene therapies
Authors: Fu Xin , Huu Viet Anh Nguyen , Duan Yaou , Kermany Daniel S , Valentim Carolina C S , Zhang Runze , Zhu Jie , Zhang Charlotte L , Sun Xiaodong , Zhang Kang
Published: June 2018

Retinal degenerative diseases are a major cause of blindness. Retinal gene therapy is a trail-blazer in the human gene therapy field, leading to the first FDA approved gene therapy product for a human genetic disease. The application of Clustered Regularly Interspaced Short Palindromic Repeat/Cas9 (CRISPR/Cas9)-mediated gene editing technology is transforming the delivery of gene therapy. We review the history, present, and future prospects of retinal gene therapy.
Detection of Two Peronospora spp., Responsible for Downy Mildew, in Opium Poppy Seed
Authors: Thangavel Tamilarasan , Jones Suzanne , Scott Jason B. , Livermore Mark , Wilson Calum R.
Published: June 2018

Downy mildew is a serious threat to opium poppy production globally. In recent years, two pathogen species, Peronospora somniferi and Peronospora meconopsidis, which induce distinct symptoms, have been confirmed in Australia. In order to manage the spread of these pathogens, identifying the sources of inoculum is essential. In this study, we assessed pathogen presence associated with poppy seed. We developed PCR and qPCR assays targeting the coxI and coxII gene regions, for the detection, differentiation, and quantification of P. somniferi and P. meconopsidis in poppy seed. These results were complemented and compared with direct seed histological examination and a seed washing combined with viability staining for oospore detection. The majority of seed lots from all harvest years contained detectable P. meconopsidis, the earliest (1987) predating the first official record of the disease in Tasmania (1996). In contrast, only seed lots harvested in 2012 or later contained P. somniferi, evidence of its more recent introduction. P. meconopsidis contamination was estimated to be as high as 33.04 pg DNA/g of seed and P. somniferi as high as 35.17 pg DNA/g of seed. Incidence of pathogen contamination of seeds, estimated via a group testing protocol, ranged from 0 to 9% (P. meconopsidis) or 0 to 11% (P. somniferi). Mycelia were predominately found external to the seed coat. Seed washing and viability staining demonstrated that putatively viable oospores were present in the majority of seed lots. Transmission testing confirmed both pathogens can be successfully transmitted from infested seed to infected seedling. PCR and qPCR pathogen assays were found to be reliable and offer a routine test for determining pathogen inoculum in poppy seeds.
Strategies for Successful Nurse-Student Preceptorships
Authors: Thomas Cynthia M. , Allen Roberta , Edwards Jane
Published: June 2018

Being a preceptor for a new nurse or a student is a great way to promote the future of nursing. However, most nurses have not been taught how to be an effective preceptor. Eight strategies for effective precepting are presented. Servant leadership is discussed as a theoretical basis for serving as a preceptor.
Basal-Cell Carcinoma With Matrical Differentiation: Report of a New Case in a Renal-Transplant Recipient and Literature Review
Authors: Kanitakis Jean , Ducroux Emilie , Hoelt Pauline , Cahen Rémi , Jullien Denis
Published: June 2018

Basal-cell carcinoma with matrical differentiation (BCC-MD) is one of the rarest pathologic variants of basal-cell carcinoma, of which 41 cases have been so far reported in detail. One of them developed in a heart-transplant recipient. We report a new case of BCC-MD occurring in a renal-transplant recipient and review the relevant literature. A 75-year-old white man who had received a renal allograft 7 years ago developed a tumor on the left temple clinically suggestive of basal-cell carcinoma. Microscopically, the tumor associated features typical of basal-cell carcinoma (basaloid lobules with peripheral palisading and clefting) and pilomatricoma (presence of shadow/ghost cells). The 2 tumor components expressed variably beta-catenin, HEA/Ber-EP4, CD10, PHLDA-1, MIB-1/Ki67, calretinin, and bcl-2. BCC-MD has no distinctive clinical features. It affects predominantly male patients with a mean age of 69 years. More than half of cases appear on the head/neck area. Some cases harbor CTNNB1 mutations. Differential diagnosis includes tumors with matrical differentiation, namely pilomatrix carcinoma. The outcome is usually favorable after surgical excision, although regional lymph node metastases developed in 2 patients.
Case Report of Myeloid Sarcoma Masquerading as In-Transit Metastasis at a Previous Melanoma Site: Avoiding a Diagnostic Pitfall
Authors: Curry Jonathan L. , Tetzlaff Michael T. , Wang Sa A. , Landon Gene , Alouch Nail , Patel Sapna P. , Nagarajan Priyadharsini , Gupta Shiva , Aung Phyu P. , Devine Catherine E. , Khoury Joseph D. , Loghavi Sanam , Prieto Victor G. , DiNardo Courtney D. , Gershenwald Jeffrey E.
Published: June 2018

Myeloid sarcoma is a rare extramedullary hematologic malignancy. Accurate and timely diagnosis may be challenging because myeloid sarcoma is known to mimic solid tumors, including hepatobiliary, nasopharyngeal, and breast carcinomas. We report a case of myeloid sarcoma that developed in the primary tumor lymphatic drainage field of a previously treated intermediate-thickness cutaneous melanoma, clinically and radiographically mimicking an in-transit metastasis, in a patient with myelodysplastic syndrome. The diagnosis of myeloid sarcoma was achieved after surgical excision of the mass and pathological examination that included extensive immunohistochemical studies. Awareness of such an unusual clinical presentation can help reduce diagnostic delay and ensure that adequate tissue is obtained for pathological examination and ancillary studies that are critical for accurate diagnosis and appropriate patient management.
Predictors of Discharge Destination From Acute Care in Patients With Traumatic Brain Injury: A Systematic Review
Authors: Zarshenas Sareh , Colantonio Angela , Alavinia Seyed Mohammad , Jaglal Susan , Tam Laetitia , Cullen Nora
Published: June 2018

Objective:

To systematically review studies on clinical and nonclinical predictors of discharge destination from acute care in patients with traumatic brain injury.

Methods:

The search was conducted using 7 databases up to December 2016. A systematic review and in-depth quality synthesis were conducted on eligible articles that met the inclusion criteria.

Results:

The search yielded 8503 articles of which 18 studies met the inclusion criteria. This study demonstrated that a larger proportion of patients with traumatic brain injury were discharged home. The main predictors of discharge to a setting with rehabilitation services versus home included increasing age, white and non-Hispanic race/ethnicity, having insurance coverage, greater severity of the injury, and longer acute care length of stay. Age was the only consistent factor that was negatively associated with discharge to inpatient rehabilitation facilities versus other institutions.

Conclusion:

Results of this study support healthcare providers in providing consultation to patients about the expected next level of cares while considering barriers that may helpful in effective discharge planning, decreasing length of stay and saving resources. These findings also suggest the need for further studies with a stronger methodology on the contribution of patients and families/caregivers to distinguish the predictors of discharge to dedicated rehabilitation facilities.
Reduced Resting and Increased Elevation of Heart Rate Variability With Cognitive Task Performance in Concussed Athletes
Authors: Huang Mu , Frantz Justin , Moralez Gilbert , Sabo Tonia , Davis Peter F. , Davis Scott L. , Bell Kathleen R. , Purkayastha Sushmita
Published: June 2018

Objective:

To examine heart rate variability (HRV) at rest and with a 2-Back cognitive task involving executive function and sustained attention in athletes during the acute phase following concussion and compare them with the controls.

Participants:

Twenty-three male and female collegiate athletes (20 ± 1 years) following (4 ± 1 days) a sports-related concussion and 23 sports- and sex-matched noninjured controls.

Procedure:

Continuous R-R interval was acquired using 3-lead electrocardiogram for 3 minutes each at rest and during the 2-Back task. HRV was quantified as percent high-frequency (HF) power.

Results:

At rest, lower percent HF power was observed in the concussed athletes (23 ± 11) compared with the controls (38 ± 14; P = .0027). However, with the 2-Back task, an increase in HF power was observed in the concussed group (39 ± 12; P = .0008) from rest and was comparable with the controls (36 ± 15). No difference in HF power between rest and 2-Back task was observed in the controls.

Conclusion:

Lower HRV was observed at rest following concussion. An increase in HRV, suggestive of enhanced prefrontal cortex (PFC) functioning, was observed during a cognitive task in the concussed athletes. Therefore, cognitive tasks as early as 4 days after injury may increase PFC functioning from rest and expedite return to learn in collegiate athletes.
SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN CHOROIDAL MELANOMA
Authors: Pellegrini Marco , Corvi Federico , Invernizzi Alessandro , Ravera Vittoria , Cereda Matteo G. , Staurenghi Giovanni
Published: June 2018

Purpose:

To describe the imaging features of choroidal melanoma using swept-source optical coherence tomography angiography (SS-OCT-A) and to evaluate its ability to display tumor intrinsic vasculature.

Methods:

Consecutive patients diagnosed with choroidal melanoma underwent a complete ophthalmic evaluation, including best-corrected visual acuity, color fundus photography, B-scan ultrasound, fluorescein angiography, indocyanine green angiography, and SS-OCT-A (PLEX Elite 9000; Carl Zeiss Meditec, Inc, Dublin, CA).

Results:

Twenty-two eyes of 22 consecutive patients were included in the study; 11 cases (50%) were treatment naive. Three lesions (14%) were located at the macula, 14 (63%) between the macula and equator, and 5 (23%) between the equator and the ora serrata. The mean tumor base and thickness were, respectively, 10.3 mm (range 5–15 mm) and 4.3 mm (range 1.5–8.9 mm). Seventeen lesions (77%) were dome shaped, whereas 5 (23%) had a mushroom configuration. Thirteen lesions (59%) were pigmented, 5 (23%) partially pigmented, and 4 (18%) amelanotic. An exudative retinal detachment was documented in 13 eyes (59%). Fluorescein angiography and indocyanine green angiography were performed in 20 patients and disclosed intrinsic microvasculature of the tumor, respectively, in 4 (20%) and 20 (100%) cases. Swept-source optical coherence tomography angiography was performed in 22 eyes and detected microvasculature of choroidal melanoma in all cases. Specifically, intrinsic vasculature could be recognized in 14 eyes (64%) using the automated choroid segmentation, 16 eyes (73%) using the automated whole eye segmentation, and in 22 eyes (100%) with fine manual adjustments of segmentation lines.

Conclusion:

Swept-source optical coherence tomography angiography represents a valid imaging technique to evaluate patients affected by choroidal melanomas. In our series, SS-OCT-A disclosed the intrinsic microvasculature of the tumor in all cases despite their size, location, and history of previous treatments.
INFLUENCE OF INVERTED INTERNAL LIMITING MEMBRANE FLAP TECHNIQUE ON THE OUTER RETINAL LAYER STRUCTURES AFTER A LARGE MACULAR HOLE SURGERY
Authors: Iwasaki Masanori , Kinoshita Takamasa , Miyamoto Hirotomo , Imaizumi Hiroko
Published: June 2018

Purpose:

To examine the influence of inverted internal limiting membrane (ILM) flap technique on the outer retinal layer structures after macular hole (MH) surgery.

Methods:

We included 24 eyes of 24 patients who underwent vitrectomy for large MHs (≥400 µm) with successful MH closure and observed for at least 6 months. Fourteen eyes were treated with inverted ILM flap technique (inverted group) and 10 with conventional ILM peeling (ILMP group). We evaluated the postoperative recovery rate of the external limiting membrane and ellipsoid zone and the best-corrected visual acuity.

Results:

The postoperative recovery rates of the external limiting membrane and ellipsoid zone in the inverted group were lower than those in the ILMP group (21.4 vs. 70.0%, P = 0.024; 0 vs. 30.0, P = 0.059, respectively). The external limiting membrane recovery period in the inverted group was significantly longer than that in the ILMP group (11.0 ± 1.7 vs. 3.4 ± 2.8 months, P = 0.015). The best-corrected visual acuity change (letters) in the inverted group was significantly smaller than that in the ILMP group (9.0 vs. 22.5, P = 0.040).

Conclusion:

The poorer anatomical and visual results associated with inverted ILM flap compared with ILM peeling suggest the limitation of the ILM flap technique to repair refractory MHs.
Quantification of Pulsed Operation of Rotary Left Ventricular Assist Devices with Wave Intensity Analysis
Authors: Bouwmeester J. Christopher , Park Jiheum , Geirsson Arnar , Valdovinos John , Bonde Pramod
Published: June 2018

The current generation of left ventricular assist devices (LVADs) provides continuous flow and has the capacity to reduce aortic pulsatility, which may be related to a range of complications associated with these devices. Pulsed LVAD operation using speed modulation presents a mechanism to restore aortic pulsatility and potentially mitigate complications. We sought to investigate the interaction of axial and centrifugal LVADs with the LV and quantify the effects of continuous and pulsed LVAD operations on LV generated wave patterns under different physiologic conditions using wave intensity analysis (WIA) method. The axial LVAD created greater wave intensity associated with LV relaxation. In both LVADs, there were only minor and variable differences between the continuous and pulsed operations. The response to physiologic stress was preserved with LVAD implantation as wave intensity increased marginally with volume loading and significantly with infusion of norepinephrine. Our findings and a new approach of investigating aortic wave patterns based on WIA are expected to provide useful clinical insights to determine the ideal operation of LVADs.
Central Venous Line and Dialysis Catheter Position Affects Drug Clearance during Continuous Renal Replacement Therapy in an Animal Model
Authors: Frithiof Robert , Bandert Anna , Larsson Anders , Lipcsey Miklos , Smekal David
Published: June 2018

In intensive care, drugs are commonly administered through central venous catheters (CVC). These catheters and central venous dialysis catheters (CVDC) are often placed in the same vessel for practical reasons. The aim of this experimental study was to investigate if the position of CVC and CVDC influences the elimination of infused drugs, during continuous renal replacement therapy (CRRT). In a randomized, cross-over model, anesthetized piglets received both a CVC and a CVDC in a jugular vein. Another CVDC was placed in a femoral vein for comparison. After baseline measurements, CRRT was performed in either of the CVDC, each CRRT-period separated by another baseline period. Hypotension was induced by peripherally given sodium nitroprusside. In the CVC, both gentamicin and noradrenaline were administered. Noradrenaline was titrated to reach a target blood pressure. When CRRT was performed using the CVDC in the same vessel as the drugs were infused, the plasma concentration of gentamicin was reduced compared with when the infusion and CVDC were in different vessels (5.66 [standard deviation (SD) ± 1.23] vs. 7.76 [SD ± 2.30] mg/l [p = 0.02]). The noradrenaline infusion rate needed to reach the target blood pressure was more than doubled (0.32 [SD ± 0.16] vs. 0.15 [SD ± 0.08] µg/kg/min [p = 0.006]). This experimental study indicates that the removal of drugs is increased if infusion is in close vicinity of the CVDC, during CRRT.
Ketamine Infusions for Outpatient Pain Management
Authors: Allen Cheryl A. , Conner Ruth , Ivester Julius R.
Published: June 2018

Current literature supports using ketamine for both acute and chronic pain management. It is imperative that the development of evidence-based protocols and policies keep pace with health care delivery to ensure patient safety. This project's objective was to formulate an outpatient ketamine infusion policy that promotes consistent and evidence-based care within a specified hospital system. This policy addresses potential side effects and minimization of adverse events by addressing patient selection, level of nursing care required, appropriate monitoring, and staff education.
“I Got My Diagnosis on a Yellow Post-it Note”
Authors: Hauken May Aasebø , Hølge-Hazelton Bibbi , Larsen Torill M.B.
Published: June 2018

Background

Cancer in young adults is rare but young adult cancer patients (YACPs) are at an increased risk of severe physical and psychosocial impairments during cancer treatment and survivorship. However, little is known about the onset of this process.

Objective

The aim of this study was to explore how young cancer survivors experience the process of being diagnosed with cancer.

Methods

A qualitative method founded on a phenomenological-hermeneutical approach was used and included in-depth interviews with 20 young adult survivors (aged 24–35 years) with different cancer diagnoses, analyzed by Systematic Text Condensation.

Results

The participants' experiences of the diagnosis process were elaborated according to 3 main themes: (1) “I felt something was wrong, but…,” (2) “The traumatic uncertainty,” and (3) “The day my world collapsed.”

Conclusion

The findings indicate that the YACPs experienced a diagnosis of cancer as a highly traumatic and long-lasting process, characterized by lack of information and uncertainty. The findings indicate that healthcare professionals do not acknowledge the vulnerable phase of life and transitional challenges of YACPs.

Implications for Clinical Practice

The findings highlight the need to raise awareness of cancer in young adulthood in the public and in the primary healthcare system, to shorten the diagnosis process, and to clarify responsibility for age-related information and psychosocial follow-up during the diagnosis process. Further research is highly warranted.
Medication Errors in the Context of Hematopoietic Stem Cell Transplantation
Authors: Pereira Lermontov Simone , Carreiro Brasil Simone , Rezende de Carvalho Magali
Published: June 2018

Background

There have been numerous efforts by health institutions and professionals to prevent and reduce medication errors.

Objectives

The aim of this study was to identify in the literature the incidence, related factors, consequences, and prevention mechanisms of medication errors in the context of hematopoietic stem cell transplantation.

Methods

This is a systematic review carried out in the databases LILACS, PubMed, PMC, EMBASE, and CINAHL databases, from January 11 to 13, 2017.

Results

Eleven studies were included in this review and presented in 4 categories of analysis. (1) occurrence—most of the medication errors were related to administration and prescription; (2) related factors—multicausal, highlighting issues including polypharmacy, lack of double checking, and similarity between the medications' names; (3) consequences—the main ones were associated with adverse reactions, with prolonged hospitalization time as outcome; (4) preventive measures—related to safe practices in pharmacotherapy, such as double check and application of the 10 rights of medication administration.

Conclusion

Medication administration is an activity of great responsibility for nursing; however, in order to achieve a decrease in medication errors, prevention strategies are necessary for the whole health team.

Implications for Practice

Practice improvements are needed including establishing institutional drug administration protocols and keeping them updated, using a computerized prescription system, and promoting patient safety with staff.
What to Do When Doctors Disagree on Diets for Women With Gestational Diabetes
Authors: Craven Kay , Haven Kelley , Kolasa Kathryn M.
Published: June 2018

Medical nutrition therapy is considered the cornerstone of treatment for gestational diabetes mellitus, even though there is no consensus on the best dietary approach to achieve optimal glycemic control and positive maternal and fetal outcomes. In this article, we present a case from our clinic of a woman with gestational mellitus, the evidence for the level of macronutrients to include in the diet, and the use of glycemic index for dietary planning. We also review the evidence for emerging dietary therapies and provide general recommendations that should be individualized to the patient.
Molecular characterization of serogroup 19 Streptococcus pneumoniae in the Czech Republic in the post-vaccine era
Authors: Žemličková Helena , Mališová Lucia , Španělová Petra , Jakubů Vladislav , Kozáková Jana , Musílek Martin , Medvecký Matej
Published: June 2018

Purpose. The aim of this study was to characterize serogroup 19 isolates resistant to macrolides and/or penicillin found among pneumococci recovered from cases of invasive and respiratory tract disease in the Czech Republic in 2014.

Methods. Pneumococcal isolates of serotypes 19A (n=26) and 19F (n=10) that were non-susceptible to penicillin and/or macrolides and had been collected in 2014 were analysed using multi-locus sequence typing (MLST). Four isolates representing the major clones were subjected to whole-genome sequencing (WGS).

Results. The penicillin-susceptible macrolide-resistant isolates of serotype 19A were mainly associated with sequence type (ST) 416 belonging to clonal complex (CC) 199, and the penicillin-resistant isolates were of serotype 19F belonging to ST1464 (CC 320). WGS revealed the presence of pilus 1, in association with pilus 2, in serotype19F isolates belonging to CC 320. Another adhesin, pneumococcal serine-rich protein (PsrP), was only present in serotype 19A isolates of ST416. Analysis of the penicillin-binding proteins (PBPs) of serotype 19F penicillin-resistant isolates (ST1464 and ST271) performed on PBP1a, 2b and 2x identified a large number of mutations in comparison to the reference strain, R6. Both isolates contained a unique PBP profile; however, they were highly similar to PBP sequences of the Taiwan19F-14 reference strain. The Pbp2b sequences of both 19F isolates showed the lowest similarity to those of the Taiwan19F-14 strain (91 % similarity), while they were also found to be distantly related to each other (94 % similarity).

Conclusions. WGS revealed specific virulence factors in antibiotic-resistant pneumococcal clones that spread rapidly in the post-vaccine era in the Czech Republic.
Interplay between coding and exonic splicing regulatory sequences
Authors: Fontrodona Nicolas , Aubé Fabien , Claude Jean-Baptiste , Polvèche Hélène , Lemaire Sébastien , Tranchevent Léon Charles , Modolo Laurent , Mortreux Franck , Bourgeois Cyril F. , Auboeuf Didier
Published: June 2018

The inclusion of exons during the splicing process depends on the binding of splicing factors to short low-complexity regulatory sequences. The relationship between exonic splicing regulatory sequences and coding sequences is still poorly understood. We demonstrate that exons that are coregulated by any splicing factor share a similar nucleotide composition bias. We next demonstrate that coregulated exons preferentially code for amino acids with similar physicochemical properties because of the non-randomness properties of the genetic code. Indeed, amino acids sharing physicochemical properties correspond to codons that have the same nucleotide composition bias. These observations reveal an unanticipated bidirectional interplay between the physicochemical features encoded by exons and exon splicing regulation by splicing factors. We propose that the splicing regulation of an exon by a splicing factor is tightly interconnected with the physicochemical properties of the exon-encoded protein domain depending on the splicing-factor affinity for specific nucleotides.
The Expression of Inflammatory Genes in 3T3-L1 Adipocytes Exhibits a Memory to Stimulation by Macrophage Secretions
Authors: Hancock Dale , Meng Luxi , Holliday Mira , Yuwono Nicole , Zhang Ning , Denyer Gareth
Published: June 2018

Obesity is characterized by increased output of inflammatory compounds from adipose tissue. Whilst the relative contribution of adipocytes and resident macrophages to this phenomenon is debated, there is no doubt that the secretions of each cell type can stimulate the expression of inflammatory genes in the other. We hypothesized that mechanisms must exist to prevent an escalating positive feedback loop between the two cell types, so that after an initial exposure to macrophage secretions, adipocytes would become desensitized to subsequent inflammatory stimulation.

We used microarrays to investigate the response of 3T3-L1 adipocytes to macrophage secretions (macrophage conditioned medium, MCM). MCM caused a rapid (<4 hours) and high amplitude (over 100-fold) rise in the expression of several inflammatory genes. For some genes, generally cytokines, expression returned to basal levels within 24 h following removal of the MCM, but other transcripts, notably those for acute phase proteins and extracellular matrix remodeling proteins, remained highly expressed even during the washout period.

Unexpectedly, some cytokine genes (e.g., iNOS, IL-6) showed an enhanced expression to a second exposure of MCM, illustrating that the transcriptome response of 3T3-L1 adipocytes retains a memory to the first stimulus. We characterized the parameters that give rise to the memory phenomenon, finding that additional stimuli do not augment or abrogate the effect. The memory is preserved for several days after the initial exposure and it is not due to a change in sensitivity to the MCM but, rather, a change in the capacity of the signal-target system. The possible mechanisms of the memory are discussed, along with the physiological ramifications should the phenomenon be replicatedin vivo.
Searching for a UV-filter in the eyes of high flying birds
Authors: Zawadzka Malgorzata , Ràcz Beatrix , Ambrosini Dario , Gørbitz Carl Henrik , Morth Jens Preben , Wilkins Alistair L. , Østeby Anja , Elgstøen Katja Benedikte Prestø , Lundanes Elsa , Rise Frode , Ringvold Amund , Wilson Steven Ray
Published: June 2018

An ultraviolet (UV)-absorbing compound of unknown identity is present in the aqueous humor of geese and other birds flying at high altitudes. A goose aqueous humor extract, that was believed to contain the UV protective compound which was designated as “compound X”, was fractionated and examined using a variety of spectroscopic techniques including LC-MS and high field one- and two dimensional-NMR methods. A series of compounds were identified but none of them appeared to be the UV protective “compound X”. It may be that the level of the UV protective compound in goose aqueous humor is much less than the compounds identified in our investigation, or it may have been degraded by the isolation and chromatographic purification protocols used in our investigations.
Dynamic Modeling and Stochastic Simulation of Metabolic Networks
Authors: Clement Emalie J. , Soliman Ghada A. , Wysocki Beata J. , Davis Paul H. , Wysocki Tadeusz A.
Published: June 2018

Increased technological methods have enabled the investigation of biology at nanoscale levels. Nevertheless, such systems necessitate the use of computational methods to comprehend the complex interactions occurring. Traditionally, dynamics of metabolic systems are described by ordinary differential equations producing a deterministic result which neglects the intrinsic heterogeneity of biological systems. More recently, stochastic modeling approaches have gained popularity with the capacity to provide more realistic outcomes. Yet, solving stochastic algorithms tend to be computationally intensive processes. Employing the queueing theory, an approach commonly used to evaluate telecommunication networks, reduces the computational power required to generate simulated results, while simultaneously reducing expansion of errors inherent to classical deterministic approaches. Herein, we present the application of queueing theory to efficiently simulate stochastic metabolic networks. For the current model, we utilize glycolysis to demonstrate the power of the proposed modeling methods, and we describe simulation and pharmacological inhibition in glycolysis to further exemplify modeling capabilities.

Author Summary

Computational biology is increasingly used to understand biological occurances and complex dynamics. Biological modeling, in general, aims to represent a biological system with computational approaches, as realistically and accurate as current methods allow. Metabolomics and metabolic systems have emerged as an important aspect of cellular biology, allowing a more sentive view for understanding the complex interactions occurring intracellularly as a result of normal or perturbed (or diseased) states. To understand metabolic changes, many researchers have commonly used Ordianary Differential Equations to produce in silico models of the in vitro system of interest. While these have been beneficial to date, continuing to advance computational methods of analyzing such systems is of interest. Stochastic models that include randomness have been known to produce more reaslistic results, yet the difficulty and intesive time component urges additional methods and techniques to be developed. In the present research, we propose using queueing networks as a technique to model complex metabolic systems, doing such with a model of glycolysis, a core metabolic pathway.
Single haplotype admixture models using large scale HLA genotype frequencies to reproduce human admixture
Authors: Simanovsky Alexandra Litinsky , Madbouly Abeer , Halagan Michael , Maiers Martin , Louzoun Yoram
Published: June 2018

The Human Leukocyte Antigen (HLA) is the most polymorphic region in humans. Anthropologists use HLA to trace populations’ migration and evolution. However, recent admixture between populations masks the ancestral haplotype frequency distribution.

We present an HLA-based method based on high-resolution HLA haplotype frequencies to resolve population admixture using a non-negative matrix factorization formalism and validated using haplotype frequencies from 56 populations. The result is a minimal set of original populations decoding roughly 90% of the total variance in the studied admixtures. These original populations agree with the geographical distribution, phylogenies and recent admixture events of the studied groups.

With the growing population of multi-ethnic individuals, the matching process for stem-cell and solid organ transplants is becoming more challenging. The presented algorithm provides a framework that facilitates the breakdown of highly admixed populations into original groups, which can be used to better match the rapidly growing population of multi-ethnic individuals worldwide.

Author Summary

Human Leukocyte Antigen (HLA) is known to be the most polymorphic region in the human genome. Anthropologists frequently use HLA to trace migration and evolution of different populations. This is due to the high linkage among HLA genes leading to the transmission of intact haplotypes from parents to offspring, hence preserving key population ancestral features.

We developed a new HLA-based method to identify admixture models in mixed populations using high-resolution HLA haplotype frequencies. Our results highlight that a single highly polymorphic locus can contain enough information to map clearly human admixture and the population genetics of the different human populations, and reproduces results based on SNP arrays.

The presented algorithm is validated using haplotype frequencies sampled from 56 worldwide populations. Under such factorization we demonstrate that 90% of the variance in these populations can be explained using a much-reduced set of 8 ethnic groups. We demonstrate that the estimated ethnic groups and admixture models agree with the geographical distribution, population phylogenies and recent historic admixture events of the studied populations.