bluuebunny/crossref_metadata_2025 huggingface dataset:
Global shifts in the phenological synchrony of species interactions over recent decades
Authors: Kharouba Heather M. , Ehrlén Johan , Gelman Andrew , Bolmgren Kjell , Allen Jenica M. , Travers Steve E. , Wolkovich Elizabeth M.
Published: April 2018

Significance

Shifts in the timing of species interactions are often cited as a consequence of climate change and, if present, are expected to have wide-reaching implications for ecological communities. Our knowledge about these shifts mostly comes from single systems, which have provided no clear picture, thus limiting our understanding of how species interactions may be responding overall. Using a new global database based on long-term data on the seasonal timing of biological events for pairwise species interactions, we find that the relative timing of interacting species has changed substantially in recent decades. The observed shifts are greater in magnitude than before recent climate change began, suggesting that there will be widespread warming-related shifts in the synchrony of species in the future.
Temperature accelerates the rate fields become forests
Authors: Fridley Jason D. , Wright Justin P.
Published: April 2018

Significance

The transition of abandoned fields into forests (secondary succession) has long informed ecologists’ understanding of community assembly and species interactions. Intriguingly, rates of secondary succession show a striking latitudinal pattern, with dominance by woody species (>50% cover) taking less than a decade in the southern United States, and up to 60 years in New England. We used a large-scale experimental network to test how multiple drivers (climate, soils, and the identity of dominant species) influence field-to-forest transitions. We found consistent evidence that climate is the strongest driver of tree establishment, suggesting that temperature limitation of succession in northern latitudes is likely to be reduced under future warming, potentially increasing rates of carbon uptake on abandoned agricultural land.
An explainable deep machine vision framework for plant stress phenotyping
Authors: Ghosal Sambuddha , Blystone David , Singh Asheesh K. , Ganapathysubramanian Baskar , Singh Arti , Sarkar Soumik
Published: April 2018

Significance

Plant stress identification based on visual symptoms has predominately remained a manual exercise performed by trained pathologists, primarily due to the occurrence of confounding symptoms. However, the manual rating process is tedious, is time-consuming, and suffers from inter- and intrarater variabilities. Our work resolves such issues via the concept of explainable deep machine learning to automate the process of plant stress identification, classification, and quantification. We construct a very accurate model that can not only deliver trained pathologist-level performance but can also explain which visual symptoms are used to make predictions. We demonstrate that our method is applicable to a large variety of biotic and abiotic stresses and is transferable to other imaging conditions and plants.
Characterization and engineering of a plastic-degrading aromatic polyesterase
Authors: Austin Harry P. , Allen Mark D. , Donohoe Bryon S. , Rorrer Nicholas A. , Kearns Fiona L. , Silveira Rodrigo L. , Pollard Benjamin C. , Dominick Graham , Duman Ramona , El Omari Kamel , Mykhaylyk Vitaliy , Wagner Armin , Michener William E. , Amore Antonella , Skaf Munir S. , Crowley Michael F. , Thorne Alan W. , Johnson Christopher W. , Woodcock H. Lee , McGeehan John E. , Beckham Gregg T.
Published: April 2018

Significance

Synthetic polymers are ubiquitous in the modern world but pose a global environmental problem. While plastics such as poly(ethylene terephthalate) (PET) are highly versatile, their resistance to natural degradation presents a serious, growing risk to fauna and flora, particularly in marine environments. Here, we have characterized the 3D structure of a newly discovered enzyme that can digest highly crystalline PET, the primary material used in the manufacture of single-use plastic beverage bottles, in some clothing, and in carpets. We engineer this enzyme for improved PET degradation capacity and further demonstrate that it can also degrade an important PET replacement, polyethylene-2,5-furandicarboxylate, providing new opportunities for biobased plastics recycling.
Vibrations of a molecule in an external force field
Authors: Okabayashi Norio , Peronio Angelo , Paulsson Magnus , Arai Toyoko , Giessibl Franz J.
Published: April 2018

Significance

The vibration of a molecule adsorbed on a surface contains essential information on the molecule–surface bond, which is important to understand the surface reactions that occur, e.g., in catalytic reactions. Accessing the vibrational energies of a single molecule is possible by combining scanning tunneling microscopy with inelastic electron spectroscopy. However, the tip of a microscope exerts a force on a nearby molecule, and possibly even induces slight structural changes. To study this problem, we have further incorporated atomic force microscopy. The relationship between the exerted forces and vibrational energies is well reproduced by a classical mechanical model. This combined technique opens the possibility to study the atomic-scale interaction of a molecule on a surface with unprecedented precision.
The images in television programs and the potential for learning unknown words
Authors: Rodgers Michael P. H.
Published: April 2018

Previous studies have indicated the potential for incidental vocabulary learning through viewing television. The assumption has been that the imagery in television helps learners acquire vocabulary because when they hear an unfamiliar word, the on-screen images provide semantic support. However, the extent to which imagery in authentic television supports learners in this way is unclear. This study examines 90 target words occurring in single seasons of television, and the degree to which their aural occurrence matched the presentation of a potentially supporting image. Results indicate differences in the way imagery supports potential vocabulary learning in documentary television compared with narrative television, and that this supporting imagery occurred concurrently with the aural form more often in documentary television. Research and pedagogical implications are discussed in detail.
The Karabakh conflict and Armenia's failed transition
Authors: Grigoryan Arman
Published: April 2018

Despite its early promise, Armenia's transition to democracy has stalled. The literature on post-Communist transitions ascribes this outcome to the autocratic preferences of its first generation of leaders, and particularly the country's first president Levon Ter-Petrossian. I argue in this article that that literature depicts a profoundly distorted picture of the Armenian politics of the 1990s. The failure of Armenia's transition was primarily due to the conflict in Nagorno-Karabakh and the political processes it set in motion.
Effectiveness of a REDD+ Project in Reducing Deforestation in the Brazilian Amazon
Authors: Simonet Gabriela , Subervie Julie , Ezzine‐de‐Blas Driss , Cromberg Marina , Duchelle Amy E.
Published: April 2018

We estimate the early effects of the pilot project to Reduce Emissions from Deforestation and forest Degradation (REDD+) in the Brazilian Amazon. This project offers a mix of interventions, including conditional payments, to reduce deforestation by smallholders who depend on swidden agriculture and extensive cattle ranching. We collected original data from 181 individual farmers. We use difference‐in‐difference (DID) and DID‐matching approaches and find evidence that supports our identification strategy. We estimate that an average of 4 ha of forest were saved on each participating farm in 2014, and that this conservation came at the expense of pastures rather than croplands. This amounts to a decrease in the deforestation rate of about 50%. We find no evidence of within‐community spillovers.
A Comparison of the Diagnostic Accuracy of Common Office Blood Pressure Measurement Protocols
Authors: Kronish Ian M , Edmondson Donald , Shimbo Daichi , Shaffer Jonathan A , Krakoff Lawrence R , Schwartz Joseph E
Published: April 2018

BACKGROUND

The optimal approach to measuring office blood pressure (BP) is uncertain. We aimed to compare BP measurement protocols that differed based on numbers of readings within and between visits and by assessment method.

METHODS

We enrolled a sample of 707 employees without known hypertension or cardiovascular disease, and obtained 6 standardized BP readings during each of 3 office visits at least 1 week apart, using mercury sphygmomanometer and BpTRU oscillometric devices (18 readings per participant) for a total of 12,645 readings. We used confirmatory factor analysis to develop a model estimating “true” office BP that could be used to compare the probability of correctly classifying participants’ office BP status using differing numbers and types of office BP readings.

RESULTS

Averaging 2 systolic BP readings across 2 visits correctly classified participants as having BP below or above the 140 mm Hg threshold at least 95% of the time if the averaged reading was <134 or >149 mm Hg, respectively. Our model demonstrated that more confidence was gained by increasing the number of visits with readings than by increasing the number of readings within a visit. No clinically significant confidence was gained by dropping the first reading vs. averaging all readings, nor by measuring with a manual mercury device vs. with an automated oscillometric device.

CONCLUSIONS

Averaging 2 BP readings across 2 office visits appeared to best balance increased confidence in office BP status with efficiency of BP measurement, though the preferred measurement strategy may vary with the clinical context.
aliFreeFold: an alignment-free approach to predict secondary structure from homologous RNA sequences
Authors: Glouzon Jean-Pierre Séhi , Ouangraoua Aïda
Published: April 2018

Motivation

Predicting the conserved secondary structure of homologous ribonucleic acid (RNA) sequences is crucial for understanding RNA functions. However, fast and accurate RNA structure prediction is challenging, especially when the number and the divergence of homologous RNA increases. To address this challenge, we propose aliFreeFold, based on a novel alignment-free approach which computes a representative structure from a set of homologous RNA sequences using sub-optimal secondary structures generated for each sequence. It is based on a vector representation of sub-optimal structures capturing structure conservation signals by weighting structural motifs according to their conservation across the sub-optimal structures.

Results

We demonstrate that aliFreeFold provides a good balance between speed and accuracy regarding predictions of representative structures for sets of homologous RNA compared to traditional methods based on sequence and structure alignment. We show that aliFreeFold is capable of uncovering conserved structural features fastly and effectively thanks to its weighting scheme that gives more (resp. less) importance to common (resp. uncommon) structural motifs. The weighting scheme is also shown to be capable of capturing conservation signal as the number of homologous RNA increases. These results demonstrate the ability of aliFreefold to efficiently and accurately provide interesting structural representatives of RNA families.

Availability and implementation

aliFreeFold was implemented in C++. Source code and Linux binary are freely available at https://github.com/UdeS-CoBIUS/aliFreeFold.

Supplementary information

Supplementary data are available at Bioinformatics online.
A new method for constructing tumor specific gene co-expression networks based on samples with tumor purity heterogeneity
Authors: Petralia Francesca , Wang Li , Peng Jie , Yan Arthur , Zhu Jun , Wang Pei
Published: April 2018

Motivation

Tumor tissue samples often contain an unknown fraction of stromal cells. This problem is widely known as tumor purity heterogeneity (TPH) was recently recognized as a severe issue in omics studies. Specifically, if TPH is ignored when inferring co-expression networks, edges are likely to be estimated among genes with mean shift between non-tumor- and tumor cells rather than among gene pairs interacting with each other in tumor cells. To address this issue, we propose Tumor Specific Net (TSNet), a new method which constructs tumor-cell specific gene/protein co-expression networks based on gene/protein expression profiles of tumor tissues. TSNet treats the observed expression profile as a mixture of expressions from different cell types and explicitly models tumor purity percentage in each tumor sample.

Results

Using extensive synthetic data experiments, we demonstrate that TSNet outperforms a standard graphical model which does not account for TPH. We then apply TSNet to estimate tumor specific gene co-expression networks based on TCGA ovarian cancer RNAseq data. We identify novel co-expression modules and hub structure specific to tumor cells.

Availability and implementation

R codes can be found at https://github.com/petraf01/TSNet.

Supplementary information

Supplementary data are available at Bioinformatics online.
In silico read normalization using set multi-cover optimization
Authors: Durai Dilip A , Schulz Marcel H
Published: April 2018

Motivation

De Bruijn graphs are a common assembly data structure for sequencing datasets. But with the advances in sequencing technologies, assembling high coverage datasets has become a computational challenge. Read normalization, which removes redundancy in datasets, is widely applied to reduce resource requirements. Current normalization algorithms, though efficient, provide no guarantee to preserve important k-mers that form connections between regions in the graph.

Results

Here, normalization is phrased as a set multi-cover problem on reads and a heuristic algorithm, Optimized Read Normalization Algorithm (ORNA), is proposed. ORNA normalizes to the minimum number of reads required to retain all k-mers and their relative k-mer abundances from the original dataset. Hence, all connections from the original graph are preserved. ORNA was tested on various RNA-seq datasets with different coverage values. It was compared to the current normalization algorithms and was found to be performing better. Normalizing error corrected data allows for more accurate assemblies compared to the normalized uncorrected dataset. Further, an application is proposed in which multiple datasets are combined and normalized to predict novel transcripts that would have been missed otherwise. Finally, ORNA is a general purpose normalization algorithm that is fast and significantly reduces datasets with loss of assembly quality in between [1, 30]% depending on reduction stringency.

Availability and implementation

ORNA is available at https://github.com/SchulzLab/ORNA.

Supplementary information

Supplementary data are available at Bioinformatics online.
The evolution of entrepreneurial ecosystems and the critical role of migrants. A Phase-Model based on a Study of IT startups in the Greater Tel Aviv Area
Authors: Schäfer Susann , Henn Sebastian
Published: April 2018

Unlike existing studies on entrepreneurial ecosystems that focus on the internal dynamics of such systems, this article argues that entrepreneurial ecosystems are linked to one another through economically specialised migrants that trigger their emergence and positively affect their future development. To illustrate the relation between migration and the dynamics of entrepreneurial ecosystems, a model is presented that distinguishes three different phases: (i) the remigration of highly skilled migrants, (ii) ‘sunshine return migration’ and (iii) the outmigration of local entrepreneurs to foreign entrepreneurial ecosystems. Even though the model is based on both existing literature and our own empirical findings in the Tel Aviv IT entrepreneurial ecosystem, it is argued that its implications also hold true for other regional contexts.
Feedback stabilization for unbounded bilinear systems using bounded control
Authors: El Ayadi Rachid , Ouzahra Mohamed
Published: April 2018

In this paper, we deal with the distributed bilinear system $ \frac{d z(t)}{d t}= A z(t) + v(t)Bz(t), $ where A is the infinitesimal generator of a semigroup of contractions on a real Hilbert space H. The linear operator B is supposed bounded with respect to the graph norm of A. Then we give sufficient conditions for weak and strong stabilizations. Illustrating examples are provided.
Integrative Treatment of Male Sexual Dysfunction (DRAFT)
Authors: Albaugh Jeffrey A.
Published: April 2018

Male sexual dysfunction is common and may include hypoactive sexual desire disorders/lack of libido, premature ejaculation, decreased ability to climax or orgasm, erectile dysfunction, and/or Peyronie’s disease. There are a myriad of cognitive behavioral, integrative, and traditional medicinal treatment options available. Each treatment has pros and cons. Patient education prior to deciding on a treatment is key. Individual patients need to understand the good and bad of each treatment to make an informed decision about how they want to meet their sexual health goals. Traditional medical treatments were discussed in Chapter 4. The aim of this chapter is to describe other nonmedicinal, nonsurgical treatment options for male sexual dysfunction.
Understanding Sexual Addiction and Hypersexuality (DRAFT)
Authors: Meyer Monica
Published: April 2018

Various terms such as sexual addiction and hypersexuality have been used to describe a problematic and destructive pattern of excessive sexual behavior that persists despite negative consequences. Proposed diagnostic criteria are presented and several typologies are described in terms of their clinical presentation and associated consequences. Pornography addiction is discussed in terms of its typical course and observed impact on sexual arousal, sexual functioning, and the romantic partnership. Interpersonal neurobiology is used to conceptualize sex addiction from the three interacting theoretical perspectives of dysfunctional neural reward circuitry, maladaptive affect regulation, and disordered intimacy (or insecure attachment). A set of standard multimodal, multidisciplinary treatment recommendations are presented in the context of the three dimensions of interpersonal neurobiology that draw upon interventions that can be integrated into a unique, client-specific treatment plan. Complimentary, alternative, and integrative methodologies are explored to form a more comprehensive approach to treatment.
The Benefits of Water Therapy for Sexual and Pelvic Problems (DRAFT)
Authors: Fleckenstein Alexa
Published: April 2018

Hydrotherapy holds promise for certain sexual and pelvic problems: Water that hits the skin acts on the entire body, triggering the neuro-endocrine-immune system, the brain, the gut-brain, and the autonomic nervous system—the neuro-endocrine axis. Hormesis (regular application of small toxic events or stressors leading to adaption and invigoration) is the mechanism that balances physiological and biochemical processes, including sexuality. Water applications result in homeostasis (balancing of internal systems—such as temperature, electrolytes, and hormones) and invigoration (strengthening of biological functions) and influence diverse bodily functions and dysfunctions loosely related to sexuality and reproduction. Dysmenorrhea, functional infertility, pregnancy, sexuality after menopause, decreased libido, breast tenderness, pelvic pain syndromes, erectile dysfunction and urinary tract infections/irritated bladder are discussed. Cold shower, cold wash, barefoot walking, warm footbath, sitzbath, full bath, warm water bottle, sauna with cold-water immersion afterwards, and some variations of these are the discussed water applications here.
The Intracerebral Hemorrhage Score: A Self-Fulfilling Prophecy?
Authors: McCracken D Jay , Lovasik Brendan P , McCracken Courtney E , Frerich Jason M , McDougal Margaret E , Ratcliff Jonathan J , Barrow Daniel L , Pradilla Gustavo
Published: April 2018

BACKGROUND

The ICH Score has become the standard for risk-stratification of 30-d mortality in patients with intracerebral hemorrhage (ICH), but treatment has evolved over the last 17 yr since its inception. We sought to determine if the ICH Score remains an accurate predictor of 30-d mortality in these high acuity patients.

OBJECTIVE

To determine the role the ICH Score has on mortality in current treatment of patients.

METHODS

A retrospective review of 554 patients treated for acute, spontaneous ICH at 2 large academic institutions between 2010 and 2014 was carried out. Surgical intervention in the form of external ventricular drain or craniotomy was performed when indicated. All patients were managed medically until discharge or death.

RESULTS

Over half (53.6%) of the patients presented with ICH of the basal ganglia/thalamus and the majority (71%) presented with ICH Scores of 0 to 2. Overall mortality was 25.1%. Observed mortality in moderate grade ICH Score patients (3 and 4) was lower than expected (49% vs 72%, P < .001) and (71% vs 97%, P < .001) when compared to the original ICH Score results. Despite differences in ICH and intraventricular hemorrhage volume, and Glasgow Coma Scale there was no difference in surgical intervention (12.2% vs 11.8%, P = .94) between the two groups. Withdrawal of care was instituted in 56.6% of all patients who died and increased with ICH Score.

CONCLUSION

In our cohort, the original ICH score did not accurately predict the mortality rate. Patient survival exceeded ICH Score-predicted mortality regardless of surgical intervention. Reevaluation of predictive scores could be useful to aid in more accurate prognoses.
EMERGEncy ID NET: Review of a 20-Year Multisite Emergency Department Emerging Infections Research Network
Authors: Santibanez Scott , Fischer Leah S , Krishnadasan Anusha , Sederdahl Bethany , Merlin Toby , Moran Gregory J , Talan David A ,   for the EMERGEncy ID NET Study Group, Mower William , Sullivan Matthew , Abrahamian Fredrick M , Ong Sam , Gross Eric , Salhi Bisan , Heilpern Katherine , Hess Jeremy , Karras David , Biros Michelle , Dunbar Lala , Takhar Sukhjit , Pollack Charles , Runge Jeffrey , Cheney Paul , Rothrock Stephen , O’Brian John , Citron Diane , Goldstein Ellie , Finegold Sydney , Nakase Janet , Newdow Michael , Merchant Guy , Pathmarajah Kavitha , Gonzalez Eva , Mulrow Mary , Bussman Silas , Kalugdnan Vernon , Peterson Stephen , Pitts Seth , Narayan Kamil , Rubin Ada , Kemble Laurie , Beckham Danielle , Neal Niccole , Yagapen Annick , Von Hofen Carol , Hatala Kathleen , Fuentes Shelley , Sibley Debbi , Colucci Ashley , Hernandez Jackeline , Cruse Hope , Usher Sarah , Hendrickson Audrey , Dehnkamp Kimberly , Zeglin Britney , Jambaulikar Guruprasad , Gorwitz Rachel , Limbago Brandi , Kuehnert Matthew , Jarvis William , Slutsker Larry , Arvay Melissa , Conn Laura
Published: April 2018

As providers of frontline clinical care for patients with acute and potentially life-threatening infections, emergency departments (EDs) have the priorities of saving lives and providing care quickly and efficiently. Although these facilities see a diversity of patients 24 hours per day and can collect prospective data in real time, their ability to conduct timely research on infectious syndromes is not well recognized. EMERGEncy ID NET is a national network that demonstrates that EDs can also collect data and conduct research in real time. This network collaborates with the Centers for Disease Control and Prevention (CDC) and other partners to study and address a wide range of infectious diseases and clinical syndromes. In this paper, we review selected highlights of EMERGEncy ID NET’s history from 1995 to 2017. We focus on the establishment of this multisite research network and the network’s collaborative research on a wide range of ED clinical topics.
Cytomegalovirus (CMV) Disease Despite Weekly Preemptive CMV Strategy for Recipients of Solid Organ and Hematopoietic Stem Cell Transplantation
Authors: Lodding I P , da Cunha Bang C , Sørensen S S , Gustafsson F , Iversen M , Kirkby N , Perch M , Rasmussen A , Sengeløv H , Mocroft A , Lundgren J D
Published: April 2018

Background

Transplant recipients presenting with cytomegalovirus (CMV) disease at the time of diagnosis of CMV DNAemia pose a challenge to a preemptive CMV management strategy. However, the rate and risk factors of such failure remain uncertain.

Methods

Solid organ transplantation (SOT) and hematopoietic stem cell transplantation (HSCT) recipients with a first episode of CMV polymerase chain reaction (PCR) DNAemia within the first year posttransplantation were evaluated (n = 335). Patient records were reviewed for presence of CMV disease at the time of CMV DNAemia diagnosis. The distribution and prevalence of CMV disease were estimated, and the odds ratio (OR) of CMV disease was modeled using logistic regression.

Results

The prevalence of CMV disease increased for both SOT and HSCT with increasing diagnostic CMV PCR load and with screening intervals >14 days. The only independent risk factor in multivariate analysis was increasing CMV DNAemia load of the diagnostic CMV PCR (OR = 6.16; 95% confidence interval, 2.09–18.11). Among recipients receiving weekly screening (n = 147), 16 (10.8%) had CMV disease at the time of diagnosis of CMV DNAemia (median DNAemia load 628 IU/mL; interquartile range, 432–1274); 93.8% of these cases were HSCT and lung transplant recipients.

Conclusions

Despite application of weekly screening intervals, HSCT and lung transplant recipients in particular presented with CMV disease at the time of diagnosis of CMV DNAemia. Additional research to improve the management of patients at risk of presenting with CMV disease at low levels of CMV DNAemia and despite weekly screening is warranted.
Search for companions in visual binary systems using precise radial-velocity measurements
Authors: Katoh Noriyuki , Itoh Yoichi , Sato Bun’ei
Published: April 2018

The frequency of triple and quadruple systems is considered to be high in the early phase of star formation. Some multiple systems decay in the pre-main-sequence phase. The multiplicity of main-sequence stars provides clues about the evolution of binary systems. This work searched for companions of five components of visual binary systems using precise radial-velocity measurements. Their radial velocities were monitored from 2007 to 2012 using the HIgh Dispersion Echelle Spectrograph (HIDES) installed on the Okayama Astrophysical Observatory (OAO) 1.88 m reflector. In combination with previous work, this work searched for companions with an orbital period of less than 9 yr for the five bodies. We found periodic variations in the radial velocities for ADS 6190 A and BDS 10966A. The radial velocities of ADS 7311 A, 31 Dra A, and 31 Dra B show significant trends. ADS 6190 A is an SB1 binary with an orbital period of 366.2 d. The minimum mass of the secondary star is 0.5$^{+0.7}_{-0.2}\,M_{\odot }$. The radial velocity of ADS 7311 A was monitored for an observational span of 3200 d. We rejected a planetary-mass companion as the cause of a decreasing trend in the radial velocity of ADS 7311 A. This work confirmed that the periodic variation in the radial velocity of BDS 10966 A is 771.1 d. Bisector analysis did not reveal a correlation between the asymmetry of a spectral line and the radial velocity of BDS 10966 A. We rejected nonradial oscillation of the photosphere as the source of the radial velocity variation. The variation may be caused by the rotational modulation owing to surface inhomogeneity. The orbital elements of 31 Dra A derived in this paper are consistent with those in a previous paper. 31 Dra A system is an SB1 binary with a minimum mass ratio of 0.30 ± 0.08. 31 Dra B exhibits a periodic variation in radial velocity. The orbital elements derived in this work are consistent with those reported previously by others. The variation is caused by a circumstellar planet.
History of the Development of Anesthesia for the Dolphin
Authors: McCormick James G. , Ridgway Sam H.
Published: April 2018

It is important for academic-minded human anesthesiologists to have an interdisciplinary perspective when engaging in cutting-edge research as well as the practice of human anesthesiology. This was a philosophy promoted by Dr. Robert Dripps, former pioneering Chairman of the Anesthesiology Department at the University of Pennsylvania (Philadelphia, Pennsylvania). Many human and veterinary anesthesiologists as well as biomedical engineers and neuroscientists benefited from Dr. Dripps’s constructive outlook personified in the quest to develop dolphin anesthesiology.

The motivation to anesthetize dolphins came from the fact that scientists and physicians wanted to study the brain of the dolphin, a brain as large as man’s. Also, investigators wanted to develop anesthesia for the dolphin in order to study the electrophysiology of the dolphin’s highly sophisticated auditory system, which facilitates the dolphin’s amazing echolocation capability.

Dolphin anesthesia involves a complex matter of unique neural control, airway anatomy, neuromuscular control of respiration, and sleep behavior.
Head Movements Allow Listeners Bilaterally Implanted With Cochlear Implants to Resolve Front-Back Confusions
Authors: Pastore M. Torben , Natale Sarah J. , Yost William A. , Dorman Michael F.
Published: April 2018

Objectives:

We report on the ability of patients fit with bilateral cochlear implants (CIs) to distinguish the front-back location of sound sources both with and without head movements. At issue was (i) whether CI patients are more prone to front-back confusions than normal hearing listeners for wideband, high-frequency stimuli; and (ii) if CI patients can utilize dynamic binaural difference cues, in tandem with their own head rotation, to resolve these front-back confusions. Front-back confusions offer a binary metric to gain insight into CI patients’ ability to localize sound sources under dynamic conditions not generally measured in laboratory settings where both the sound source and patient are static.

Design:

Three-second duration Gaussian noise samples were bandpass filtered to 2 to 8 kHz and presented from one of six loudspeaker locations located 60° apart, surrounding the listener. Perceived sound source localization for seven listeners bilaterally implanted with CIs, was tested under conditions where the patient faced forward and did not move their head and under conditions where they were encouraged to moderately rotate their head. The same conditions were repeated for 5 of the patients with one implant turned off (the implant at the better ear remained on). A control group of normal hearing listeners was also tested for a baseline of comparison.

Results:

All seven CI patients demonstrated a high rate of front-back confusions when their head was stationary (41.9%). The proportion of front-back confusions was reduced to 6.7% when these patients were allowed to rotate their head within a range of approximately ± 30°. When only one implant was turned on, listeners’ localization acuity suffered greatly. In these conditions, head movement or the lack thereof made little difference to listeners’ performance.

Conclusions:

Bilateral implantation can offer CI listeners the ability to track dynamic auditory spatial difference cues and compare these changes to changes in their own head position, resulting in a reduced rate of front-back confusions. This suggests that, for these patients, estimates of auditory acuity based solely on static laboratory settings may underestimate their real-world localization abilities.
Primary hyperparathyroidism: recent advances
Authors: Walker Marcella D. , Bilezikian John P.
Published: April 2018

Purpose of review

The purpose of this review is to describe recent advances and changes in the evaluation and management of primary hyperparathyroidism (PHPT).

Recent findings

Although it has long been recognized that asymptomatic PHPT is associated with bone loss, particularly at cortical skeletal sites when evaluated with dual-energy X-ray absorptiometry, new imaging techniques suggest that trabecular skeletal deterioration as well as clinically silent vertebral fractures and nephrolithiasis are common. Nonclassical targets of asymptomatic PHPT as well as the effect of vitamin D deficiency and treatment upon PHPT presentation have been the subject of recent intense investigation. Randomized clinical trials are now available regarding the effect of parathyroidectomy (PTX) upon both classical and nonclassical target organs. They have confirmed results from observational studies with regard to the skeletal benefits of PTX but have not consistently shown improvements in nonclassical symptoms.

These findings have led to recommendations for more extensive renal and skeletal evaluation and broader criteria for PTX in PHPT. In addition to dual-energy X-ray absorptiometry, vertebral and renal imaging is recommended. When available, trabecular imaging techniques may be helpful. PTX criteria now include subclinical kidney stones, vertebral fractures and hypercalciuria, in addition to those based on age, serum calcium, bone densitometry and renal function.
Split-Depressed Lateral Tibial Plateau Fractures: A Comparison of Augmented Percutaneous Screws Versus Augmented Plate and Screw Construct in a Cadaveric Model
Authors: Bowles Richard J. , Chadayammuri Vivek , Baldini Todd , Brecevich Antonio , Mauffrey Cyril
Published: April 2018

Objectives:

To compare the strength of fixation of percutaneous screw versus plate/screw fixation in a paired cadaver model of OTA 41-B3 (Schatzker type II) split-depression fractures of the lateral tibial plateau.

Methods:

Six matched pairs of cadaveric knees were acquired. An OTA 41-B3 (Schatzker type II) split-depression fracture was created in all specimens using a standardized method. One specimen from each matched pair of knees was fixed with percutaneous screws, and the other was fixed with a plate/screw construct. All specimens underwent augmentation of the central metaphyseal defect with calcium phosphate. Mean residual displacement (depression) was measured on thin-slice high-resolution computed tomography using a standardized methodology following 3 experimental conditions: (1) after they were fixed, before loading; (2) unloaded cycling (simulating postoperative range of motion exercises); and (3) loaded cycling (simulating postoperative weight-bearing). Load to failure was also compared.

Results:

After adjustment for baseline measurements, there was no significant difference in mean residual depression of the lateral tibial plateau between treatments groups after unloaded or loaded cyclic testing. Mean residual depression was less than 1 mm in both the treatment groups. Load to failure was statistically equivalent between treatment groups.

Conclusions:

In our cadaveric study, in combination with calcium phosphate augmentation for both methods, percutaneous screw fixation conferred comparable strength of fixation compared with plate/screw constructs for treatment of OTA 41-B3 (Schatzker type II) tibial plateau fractures.
Operative Treatment of Talar Head Fractures: Surgical Technique
Authors: Anderson Michael R. , Ketz John P. , Flemister Adolph Sam
Published: April 2018

Talar head fractures represent a rare subtype of injury to the talus. Clinical series of talar head fractures are nonexistent in the current literature, and treatment of these injuries is based on expert opinion. Many authors recommend a single-incision approach to open reduction and internal fixation of talar head fractures; however, we have found that a 2-incision approach allows for optimal visualization while facilitating proper implant placement. We present a description of our technique and our clinical experience treating 8 of these rare injuries.
Surgical Treatment of Supracondylar Humeral Fractures in a Freestanding Ambulatory Surgery Center is as Safe as and Faster and More Cost-Effective Than in a Children's Hospital
Authors: Rider Carson M. , Hong Victor Y. , Westbrooks Timothy J. , Wang Jiajing , Sheffer Benjamin W. , Kelly Derek M. , Spence David D. , Flynn John M. , Sawyer Jeffrey R.
Published: April 2018

Background:

Despite an 88% increase in the number of pediatric fractures treated in ambulatory surgery centers (ASCs) over a 10-year period, few studies have compared outcomes of fracture treatment performed in a freestanding ASC compared with those performed in the hospital (HOSP) or hospital outpatient department (HOPD). The purpose of this study was to compare clinical and radiographic outcomes, treatment times, and costs for treatment of Gartland type II supracondylar humeral (SCH) fracture in the ASC, HOSP, and HOPD.

Methods:

Retrospective review identified pediatric patients with isolated Gartland type II SCH fractures who had closed reduction and percutaneous pinning (CRPP) by board-certified orthopaedic surgeons from January 2012 to September 2016. On the basis of the location of their treatment, patients were divided into 3 groups: HOSP, HOPD, and ASC. All fractures were treated with CRPP under fluoroscopic guidance using 2 parallel or divergent smooth Kirschner wires. Radiographs obtained before and after CRPP and at final follow-up noted the anterior humeral line index (HLI) and Baumann angle. Statistical analysis compared all 3 groups for outcomes, complications, treatment time/efficiency, and charges.

Results:

Record review identified 231 treated in HOSP, 35 in HOPD, and 50 in ASC. Radiographic outcomes in terms of Baumann angle and HLI did not differ significantly between the groups at any time point except preoperatively when the HLI for the HOSP patients was lower (P=0.02), indicating slightly greater displacement than the other groups. Overall complication rates were not significantly different among the groups, nor were occurrences of individual complications. The mean surgical time was significantly shorter (P<0.0001) in ASC patients than in HOPD and HOSP patients, and total charges were significantly lower (P<0.001).

Conclusions:

Gartland type II SCH fractures can be safely treated in a freestanding ASC with excellent clinical and radiographic outcomes equal to those obtained in the HOSP and HOPD; treatment in the ASC also is more efficient and cost-effective.

Level of Evidence:

Level III—retrospective comparative study.
A Systematic Review of the Utility of the Hoffmann Sign for the Diagnosis of Degenerative Cervical Myelopathy
Authors: Fogarty Alexandra , Lenza Eric , Gupta Gaurav , Jarzem Peter , Dasgupta Kaberi , Radhakrishna Mohan
Published: April 2018

Study Design.

Systematic review.

Objective.

To determine the validity of the Hoffmann sign for the detection of degenerative cervical myelopathy (DCM) for patients presenting with cervical complaints.

Summary of Background Data.

While physical examination maneuvers are often used to diagnose DCM, no previous review has synthesized diagnostic accuracy data.

Methods.

Medline, Embase, and HealthStar were searched for articles from January 1, 1947 to March 1, 2017 using the following terms: Spinal Cord Diseases, Spinal Cord Compression, Cervical Vertebrae, Signs and Symptoms, Physical Examination, Epidemiologic studies, Epidemiologic Research Design, Predictive Value of Tests, and Myelopathy. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist was applied to determine the level of evidence. Articles included were published in English or French language, rated as QUADAS level 3 or higher with a minimum 10 patients presenting with cervical complaints having undergone the Hoffman sign. Excluded studies recruited patients with a nondegenerative type of cervical myelopathy, and/or no evaluation with magnetic resonance imaging.

Results.

A total of 589 articles were selected for review. Following the application of inclusion and exclusion criteria, 45 articles were analyzed using the QUADAS checklist. Only of three articles were of QUADAS quality 3 or higher. Analysis of combined data from 2/3 studies indicated that the Hoffman sign has a positive likelihood ratio of 2.2 (95% CI 1.5–3.3) and a negative likelihood ratio of 0.63 (95% CI 0.5–0.8).

Conclusion.

A positive Hoffman alone is unlikely to lead to more than a small change in estimated probability of DCM as compared with the gold standard test (magnetic resonance imaging). Variability in results across individual studies may result from differences in study design. There are insufficient data to support use of the Hoffman sign alone to confirm or refute a diagnosis of DCM.

Level of Evidence: 1
Long-term Outcomes With Ifosfamide-based Hypofractionated Preoperative Chemoradiotherapy for Extremity Soft Tissue Sarcomas
Authors: Pennington Joseph Daniel , Eilber Fritz C. , Eilber Frederick R. , Singh Arun S. , Reed Jarred P. , Chmielowski Bartosz , Eckardt Jeffrey J. , Bukata Susan V. , Bernthal Nicholas M. , Federman Noah , Nelson Scott D. , Dry Sarah M. , Wang Pin-Chieh , Luu Michael , Selch Michael T. , Steinberg Michael L. , Kalbasi Anusha , Kamrava Mitchell
Published: April 2018

Objectives:

The objective of this study was to analyze outcomes for patients with soft tissue sarcoma of the extremities using neoadjuvant ifosfamide-based chemotherapy and hypofractionated reduced dose radiotherapy, followed by limb-sparing surgery.

Materials and Methods:

An Institutional Review Board (IRB)-approved retrospective review of patients treated at a single institution between 1990 and 2013 was performed. In total, 116 patients were identified who received neoadjuvant ifosfamide-based chemotherapy and 28 Gy in 8 fractions of preoperative radiation (equivalent dose in 2 Gray fractions, 31.5 Gy [α/β 10] 36.4 Gy [α/β 3]) followed by limb-sparing surgery. Local recurrence (LR), distant failure (DF), and overall survival (OS) were calculated. Univariate and multivariate analysis for LR, DF, and OS were performed using Cox analysis. Statistical significance was set at aP<0.05.

Results:

Median follow-up was 5.9 years (range, 0.3 to 24 y). Actuarial LR at 3/6 years was 11%/17%, DF at 3/6 years was 25%/35%, and OS at 3/6 years was 82%/67%. On multivariate analysis, only a positive surgical margin was significantly correlated with worse local control (P=0.005; hazard ratio [HR], 18.33; 95% confidence interval (CI), 2.41-139.34). Age over 60 years (P=0.03; HR, 2.34; 95% CI, 1.10-4.98) and tumor size over 10 cm compared with tumor size ≤5 cm (P=0.03; HR, 3.32; 95% CI, 1.15-9.61) were associated with worse OS.

Conclusions:

Soft tissue extremity sarcoma patients treated using reduced dose hypofractionated preoperative radiotherapy in combination with ifosfamide-based chemotherapy shows acceptable local control and warrants further investigation.
Clinical Significance of Lymph Node Metastasis in the Mesentery of the Terminal Ileum in Patients With Right-sided Colon Tumors at Different Locations
Authors: Kang Sung Il , Kim Duck-Woo , Shin Eun , Kim Myung Jo , Son Il Tae , Oh Heung-Kwon , Kang Sung-Bum
Published: April 2018

BACKGROUND:

There are limited reports on peri-ileal lymph node metastasis in patients with right-sided colon cancer, and little is known about their clinical significance.

OBJECTIVE:

This study aimed to examine the role of tumor location in the prevalence and clinical significance of peri-ileal lymph node metastasis in patients with right-sided colon cancer.

DESIGN:

This is a retrospective study from a prospective cohort database.

SETTINGS:

The study was conducted at a tertiary referral hospital.

PATIENTS:

Patients with right-sided colon cancer treated with radical surgery in a hospital between May 2006 and September 2016 were included.

MAIN OUTCOME MEASURES:

The frequency of peri-ileal lymph node metastasis in the study cohort and the role of tumor location and the clinical characteristics of patients with peri-ileal lymph node metastasis were determined.

RESULTS:

We examined 752 cases with right-sided colon cancer including 82 cecal, 554 ascending colon, and 116 hepatic flexure cancer. Twenty patients (2.7%) had peri-ileal lymph node metastasis. The incidence of metastasis to peri-ileal lymph nodes was 7.3% (6/82) in patients with cecal cancer, 2.2% (12/554) in patients with ascending colon cancer, and 1.7% (2/116) in patients with hepatic flexure cancer. Three patients had stage III cancer and 17 had stage IV. All 3 patients with positive peri-ileal lymph nodes and stage III cancer had cecal tumors. In contrast, all patients with ascending colon or hepatic flexure cancer and positive peri-ileal lymph nodes had stage IV cancer.

LIMITATIONS:

The results were limited by the retrospective design of the study and the small number of patients with peri-ileal lymph node metastasis.

CONCLUSIONS:

Peri-ileal lymph node metastasis was rare even in right-sided colon cancer and occurred mainly in stage IV. However, it occurred in some patients with locally advanced cecal cancer. These results suggest that optimal resection of the mesentery of the terminal ileum might have clinical benefit, especially in curative surgery for cecal cancer. See Video Abstract at http://links.lww.com/DCR/A556.
What is new in the management of poor ovarian response in IVF?
Authors: Vaiarelli Alberto , Cimadomo Danilo , Ubaldi Nicolò , Rienzi Laura , Ubaldi Filippo Maria
Published: April 2018

Purpose of review

The management and treatment of patients with poor ovarian response is still a controversial issue in IVF. Increasing evidences demonstrate that the number of oocytes retrieved after a controlled ovarian stimulation (COS) greatly influences the clinical outcome in terms of cumulative live birth per started cycle. For this reason, any COS should aim to optimize the number of oocytes according to the ovarian reserve of the patient. The aim of this review is to provide an overview of new strategies proposed to manage poor responders according to the novel POSEIDON classification.

Recent findings

Gonadotrophins cannot compensate for the absence of follicles in the ovary, therefore, COS in poor responders may benefit from the exploitation of multiple follicular waves within a single ovarian cycle, for instance, through luteal phase stimulation or double stimulation (follicular plus luteal) in the same ovarian cycle (DuoStim) protocols.

Many strategies have been proposed to manage poor responder patients, however, a consensus upon which is the most beneficial has not been yet reached. DuoStim is the most promising approach to increase the number of oocytes collected in a single ovarian cycle; however, more embryological and clinical data is required, as well as an analysis of its cost-effectiveness.