bluuebunny/crossref_metadata_2025 huggingface dataset:
NEXAFS spectroscopy and site-specific fragmentation of N-methylformamide, N,N-dimethylformamide, and N,N-dimethylacetamide
Authors: Salén Peter , Yatsyna Vasyl , Schio Luca , Feifel Raimund , Richter Robert , Alagia Michele , Stranges Stefano , Zhaunerchyk Vitali
Published: June 2016

Near-edge X-ray absorption fine-structure (NEXAFS) spectra measured at the C, N, and O K-edges for three molecules containing the amide moiety, N-methylformamide (HCONHCH3), N,N-dimethylformamide (HCON(CH3)2), and N,N-dimethylacetamide (CH3CON(CH3)2) are presented. These molecules have similar structures and differ by the number of methyl groups located at the molecular ends. The fragmentation of these molecules after resonant excitation at different K-edge resonances is also investigated, using a 3D-ion imaging time-of-flight spectrometer. A comparison between the molecules with respect to the relative contributions of the fragments created upon excitation at distinct resonances reveals site-specific fragmentation. Further information about the character of the core-excitation and dissociation process is obtained from the angular distributions of the ion fragments.
Exploring interface morphology of a deeply buried layer in periodic multilayer
Authors: Das Gangadhar , Khooha Ajay , Singh A. K. , Srivastava A. K. , Tiwari M. K.
Published: June 2016

Long-term durability of a thin film device is strongly correlated with the nature of interface structure associated between different constituent layers. Synthetic periodic multilayer structures are primarily employed as artificial X-ray Bragg reflectors in many applications, and their reflection efficiency is predominantly dictated by the nature of the buried interfaces between the different layers. Herein, we demonstrate the applicability of the combined analysis approach of the X-ray reflectivity and grazing incidence X-ray fluorescence measurements for the reliable and precise determination of a buried interface structure inside periodic X-ray multilayer structures. X-ray standing wave field (XSW) generated under Bragg reflection condition is used to probe the different constituent layers of the W- B4C multilayer structure at 10 keV and 12 keV incident X-ray energies. Our results show that the XSW assisted fluorescence measurements are markedly sensitive to the location and interface morphology of a buried layer structure inside a periodic multilayer structure. The cross sectional transmission electron microscopy results obtained on the W-B4C multilayer structure provide a deeper look on the overall reliability and accuracy of the XSW method. The method described here would also be applicable for nondestructive characterization of a wide range of thin film based semiconductor and optical devices.
On the widths of Stokes lines in Raman scattering from molecules adsorbed at metal surfaces and in molecular conduction junctions
Authors: Gao Yi , Galperin Michael , Nitzan Abraham
Published: June 2016

Within a generic model we analyze the Stokes linewidth in surface enhanced Raman scattering (SERS) from molecules embedded as bridges in molecular junctions. We identify four main contributions to the off-resonant Stokes signal and show that under zero voltage bias (a situation pertaining also to standard SERS experiments) and at low bias junctions only one of these contributions is pronounced. The linewidth of this component is determined by the molecular vibrational relaxation rate, which is dominated by interactions with the essentially bosonic thermal environment when the relevant molecular electronic energy is far from the metal(s) Fermi energy(ies). It increases when the molecular electronic level is close to the metal Fermi level so that an additional vibrational relaxation channel due to electron-hole (eh) exciton in the molecule opens. Other contributions to the Raman signal, of considerably broader linewidths, can become important at larger junction bias.
Morphological cladistic analysis resolves the generic limits of the Neotropical potter wasp genera Minixi Giordani Soika and Pachyminixi Giordani Soika (Hymenoptera : Vespidae : Eumeninae)
Authors: Hermes Marcel G. , de Oliveira Letícia A.
Published: June 2016

The generic classification of Neotropical Eumeninae has been termed chaotic, and synonymisation of taxa has become constant in recent years. Recognition of some generic limits are problematic due to features showing a great deal of variation, such as the length of the first metasomal tergum. This applies to the Neotropical Alphamenes van der Vecht, Minixi Giordani Soika and Pachyminixi Giordani Soika. Minixi has already been demonstrated to be paraphyletic in regards to Pachyminixi. These taxa are the focus of the present study, which used morphological data to infer the phylogenetic relationships among their constituent species. A total of 14 taxa and 34 characters were subjected to cladistic analysis under implied weighting. A single most-parsimonious cladogram was obtained, recovering Pachyminixi as monophyletic. Minixi, however, was paraphyletic relative to Pachyminixi and they are thus synonymised, with the former name having priority. A new species from Mexico, Minixi mariachii, sp. nov., is described. Minixi joergenseni bicingulatus (Zavattari, 1912) is synonymised under M. joergenseni (Schrottky, 1909), comb. nov. Additional new combinations are: Minixi arechavaletae (Brèthes, 1903), comb. nov., M. bifasciatum (von Schulthess, 1904), comb. nov., M. brethesi (Bertoni, 1927), comb. nov., M. sumichrasti (de Saussure, 1875), comb. nov., and M. uruguyense (de Saussure, 1855), comb. nov. Illustrations and a new key to species of Minixi are provided. The present study enhances our knowledge on Neotropical potter wasp systematics, providing one further step into a natural classification for a group whose taxonomy has suffered from irrational splitting of genera in the past century.
Two recently discovered species of Apiomorpha (Hemiptera: Eriococcidae) feeding on eudesmid eucalypts in Western Australia reaffirm host conservatism in this gall-inducing scale insect genus
Authors: Mills Penelope J. , Semple Thomas L. , Garland Kathleen L. S. , Cook Lyn G.
Published: June 2016

Gall-inducing insects are relatively host-specific compared with their non-galling relatives. In Australia, there have been at least four origins of gall induction among eriococcid scale insects, with the most species-rich genus, Apiomorpha, inducing galls only on species of Eucalyptus. Here we describe two recently discovered species of Apiomorpha that induce galls on eudesmid eucalypts in Western Australia: Apiomorpha gongylocarpae, sp. nov., which is very similar morphologically to A. pomaphora, and A. jucundacrispi, sp. nov., the adult females of which induce an unusual gall covered in woody protrusions that, when older, have a knobbly appearance. Using molecular, morphological and host-association data, we show that these two species form a monophyletic group with the only other species of Apiomorpha that feed on eudesmid eucalypts (A. hilli and A. pomaphora). We place all four species of eudesmid-feeding Apiomorpha in the A. hilli species group, thus revising the current placement of A. pomaphora by removing it from the A. malleeacola species group. This study highlights additional faunal diversity endemic to Western Australia, with two of the four species being restricted to the globally recognised biodiversity hotspot of the South West Australia Floristic Region. http://zoobank.org/urn:lsid:zoobank.org:pub:D6245EB6-903E-483C-B69B-3ED7EA35AD04.
Congruence between male upper lip morphology and molecular phylogeny in Parapolycope (Ostracoda), with two new species from Korea
Authors: Karanovic Ivana , Tanaka Hayato , Tsukagoshi Akira
Published: June 2016

The ostracod genera Parapolycope Klie, 1939 and Kliecope Tanaka, Tsukagoshi & Karanovic, 2014 have a sexually dimorphic upper lip, and males use their lip during courtship. Here we study the male upper lip of 14 species in order to find homologous structures. For this purpose, the lip is divided into six homologous parts, determined by their relative position on the lip and the lip’s position in relation to other body parts. We found that the distal part (‘c’) is the most variable across taxa, probably due to high sexual selection. Six characters of the male upper lip are used in our cladistic analysis, along with another 12, in order to study phylogenetic relationships between Parapolycope species from East Asia. In addition, 18S rRNA is used to reconstruct molecular phylogeny and test the congruence between morphological and molecular data. The recovered topology on all obtained trees is almost identical, emphasising the importance of the male upper lip morphology in interpreting phylogenetic relationships in this peculiar ostracod group. Parapolycope viriosa, sp. nov. and P. widoensis, sp. nov. from marine interstitial habitats in South Korea are described here. To aid further identification of the 12 East Asian Parapolycope species we provide a taxonomic key.
Salinity of deep groundwater in California: Water quantity, quality, and protection
Authors: Kang Mary , Jackson Robert B.
Published: June 2016

Significance

Groundwater withdrawals are increasing across the United States, particularly in California, which faces a growing population and prolonged drought. Deep groundwater aquifers provide an alternative source of fresh and saline water that can be useable with desalination and/or treatment. In the Central Valley alone, fresh groundwater volumes can be increased almost threefold, and useable groundwater volumes can be increased fourfold if we extend depths to 3,000 m. However, some of these deep groundwater resources are vulnerable to contamination from oil/gas and other human activities. Our findings provide the first estimates, to our knowledge, of underground sources of drinking water depths and volumes in California and show the need to better characterize and protect deep groundwater aquifers.
Bacterial lipids activate, synergize, and inhibit a developmental switch in choanoflagellates
Authors: Woznica Arielle , Cantley Alexandra M. , Beemelmanns Christine , Freinkman Elizaveta , Clardy Jon , King Nicole
Published: June 2016

Significance

Bacterial symbionts profoundly influence the biology of their animal hosts, yet complex interactions between animals and their resident bacteria often make it challenging to characterize the molecules and mechanisms. Simple model systems can reveal fundamental processes underlying interactions between eukaryotes and their associated microbial communities and provide insight into how bacteria regulate animal biology. In this study we isolate and characterize bacterial molecules that regulate multicellular development in the closest living relatives of animals, the choanoflagellate. We find that multiple bacterially derived lipids converge to activate, enhance, and inhibit choanoflagellate multicellular development.
Analysis of tandem gene copies in maize chromosomal regions reconstructed from long sequence reads
Authors: Dong Jiaqiang , Feng Yaping , Kumar Dibyendu , Zhang Wei , Zhu Tingting , Luo Ming-Cheng , Messing Joachim
Published: June 2016

Significance

Gene copy number variation plays an important role in genome evolution and the penetrance of phenotype variations within a species. We have applied new sequencing and physical mapping strategies to obtain long chromosomal regions from a single DNA preparation in each method that comprise tandem repeated gene copies interspersed with transposable elements that comprise about 85% of the genome. This approach should reduce the time and cost to study haplotype variation of complex genomes like those from mammalian and plant species.
Predicting the Stability of Endangered Stonecats in the LaPlatte River, Vermont
Authors: Puchala Elizabeth A. , Parrish Donna L. , Donovan Therese M.
Published: June 2016

StonecatsNoturus flavusin Vermont conform to a rare distribution pattern (as designated by Rabinowitz 1981) because their known distribution within the state is limited to the LaPlatte and Missisquoi rivers. We focused on Stonecats in the LaPlatte River to predict the stability of the population. During 2012–2014, we captured Stonecats via backpack electrofishing; fish were PIT‐tagged (>90 mm TL) and marked with visible implant elastomer. Among the 1,671 Stonecats that were captured, 1,252 were PIT‐tagged. Only 156 (12%) of the PIT‐tagged fish were recaptured, and only 22 of those individuals were recaptured more than once. The Pradel model in Program MARK was used to estimate apparent survival (Φ) and seniority, which were used to derive the rate of population change (λ) for the Stonecat encounter histories we studied. We examined a total of 64 models in our candidate set, with the following covariates: TL at first capture, maximum temperature, season, maximum discharge, and area sampled. Survival estimates were highest in the spring (range of daily Φ = 0.9993–0.9995) and increased with greater TL at first capture. We also estimated increases in capture probability with increasing area sampled. We derived an annual λ of 0.9794, which indicates a slightly decreasing population. However, our λ estimate contained uncertainty that was likely increased due to the low recapture rates. Additional years of data could increase the accuracy of the λ estimate. In the meantime, we have provided insight into Stonecat population parameters that were otherwise unknown.

Received December 22, 2015; accepted March 1, 2016 Published online June 29, 2016
Money, migration and masculinity among artisanal miners in Katanga (DR Congo)
Authors: Cuvelier Jeroen
Published: June 2016

The Katangese artisanal mining sector has grown spectacularly since the late 1990s. Faced with political instability and economic crisis, tens of thousands of men have moved to the mining areas in order to find new sources of income. This article offers a detailed ethnographic description of how male migrant workers experience and cope with the challenging realities of life on the mines against the backdrop of recent changes in Katanga’s political economy. More specifically, it examines the relationship between money, migration and masculinity through an extended case study of a money dispute among a group of artisanal miners working in the Kalabi mine near Lwambo, a small town situated 20 kilometres north of Likasi. It is found that the conspicuous consumption of money plays a vital role in the mining subculture; that credit and debt dominate life on the mines; and that artisanal mining has given rise to significant changes in gender relations and household organisation.
Affine pavings and the enhanced nilpotent cone
Authors: Mautner Carl
Published: June 2016

We construct affine pavings of Springer-type fibers over the enhanced nilpotent cone. This resolves a question of Achar-Henderson and implies the existence of perverse parity sheaves on the enhanced nilpotent cone.
The Szlenk power type and tensor products of Banach spaces
Authors: Draga Szymon , Kochanek Tomasz
Published: June 2016

We prove a formula for the Szlenk power type of the injective tensor product of Banach spaces with Szlenk index at most

ω
\omega

. We also show that the Szlenk power type as well as summability of the Szlenk index are separably determined, and we extend some of our recent results concerning direct sums.
Contact nilpotent Lie algebras
Authors: Alvarez M. A. , Rodríguez-Vallarte M. , Salgado G.
Published: June 2016

In this work we show that for

n
≥
1

n\geq 1

, every finite

(
2
n
+
3
)

(2n+3)

-dimensional contact nilpotent Lie algebra

g

\mathfrak {g}

can be obtained as a double extension of a contact nilpotent Lie algebra

h

\mathfrak {h}

of codimension 2. As a consequence, for

n
≥
1

n\geq 1

, every

(
2
n
+
3
)

(2n+3)

-dimensional contact nilpotent Lie algebra

g

\mathfrak {g}

can be obtained from the 3-dimensional Heisenberg Lie algebra

h

3

\mathfrak {h}_3

, by applying a finite number of successive series of double extensions. As a byproduct, we obtain an alternative proof of the fact that a

(
2
n
+
1
)

(2n+1)

-nilpotent Lie algebra

g

\mathfrak {g}

is a contact Lie algebra if and only if it is a central extension of a nilpotent symplectic Lie algebra.
The EGH Conjecture and the Sperner property of complete intersections
Authors: Harima Tadahito , Wachi Akihito , Watanabe Junzo
Published: June 2016

Let

A
A

be a graded complete intersection over a field and

B
B

the monomial complete intersection with the generators of the same degrees as

A
A

. The EGH conjecture says that if

I
I

is a graded ideal in

A
A

, then there should be an ideal

J
J

in

B
B

such that

B

/

J

B/J

and

A

/

I

A/I

have the same Hilbert function. We show that if the EGH conjecture is true, then it can be used to prove that every graded complete intersection over any field has the Sperner property.
Structural distinctions of fast and slow bacterial luciferases revealed by phylogenetic analysis
Authors: Deeva Anna A. , Temlyakova Evgenia A. , Sorokin Anatoly A. , Nemtseva Elena V. , Kratasyuk Valentina A.
Published: June 2016

Motivation: Bacterial luciferases are heterodimeric enzymes that catalyze a chemical reaction, so called bioluminescence, which causes light emission in bacteria. Bioluminescence is vastly used as a reporter system in research tools and commercial developments. However, the details of the mechanisms that stabilize and transform the reaction intermediates as well as differences in the enzymatic kinetics amongst different bacterial luciferases remain to be elucidated.

Results: Amino acid sequences alignments for 21 bacterial luciferases (both α- and β-subunits) were analyzed. For α-subunit, containing the enzyme active center, 48 polymorphic amino acid positions were identified. According to them, the sequences fell into two distinct groups known as slow and fast based on the decay rate of the bioluminescence reaction. The differences in the enzyme active site induced by structural polymorphism are analyzed.

Availability and implementation: Three-dimensional models of Photobacterium leiognathi luciferase and Vibrio harveyi luciferase (with reconstructed mobile loop) are freely available at PMDB database: PM0080525 and PM0080526, respectively.

Contact:  adeeva@sfu-kras.ru

Supplementary information:  Supplementary data are available at Bioinformatics online.
Nonparametric binary instrumental variable analysis of competing risks data
Authors: Richardson Amy , Hudgens Michael G. , Fine Jason P. , Brookhart M. Alan
Published: June 2016

In both observational studies and randomized trials with noncompliance, unmeasured confounding may exist which may bias treatment effect estimates. Instrumental variables (IV) are a popular technique for addressing such confounding, enabling consistent estimation of causal effects. This paper proposes nonparametric IV estimators for censored time to event data that may be subject to competing risks. A simple, plug-in estimator is introduced using nonparametric estimators of the cumulative incidence function, with confidence intervals derived using asymptotic theory. To provide an overall test of the treatment effect, an integrated weighted difference statistic is suggested, which is applicable to data with and without competing risks. Simulation studies demonstrate that the methods perform well with realistic samples sizes. The methods are applied to assess the effect of infant or maternal antiretroviral therapy on transmission of HIV from mother to child via breastfeeding using data from a large, recently completed randomized trial in Malawi where noncompliance with assigned treatment may confound treatment effect estimates.
Seismological investigation of the 2016 January 6 North Korean underground nuclear test
Authors: Zhao Lian-Feng , Xie Xiao-Bi , Wang Wei-Min , Hao Jin-Lai , Yao Zhen-Xing
Published: June 2016

Seismology plays an important role in characterizing potential underground nuclear tests. Using broad-band digital seismic data from Northeast China, South Korea and Japan, we investigated the properties of the recent seismic event occurred in North Korea on 2016 January 6. Using a relative location method and choosing the previous 2006 explosion as the master event, the 2016 event was located within the North Korean nuclear test site, with its epicentre at latitude 41.3003°N and longitude 129.0678°E, approximately 900 m north and 500 m west of the previous event on 2013 February 12. Based on the error ellipse, the relocation uncertainty was approximately 70 m. Using the P/S spectral ratios, including Pg/Lg, Pn/Lg and Pn/Sn, as the discriminants, we identify the 2016 event as an explosion rather than an earthquake. The body-wave magnitude calculated from regional wave Lg is mb(Lg) equal to 4.7 ± 0.2. Adopting an empirical magnitude–yield relation, and assuming that the explosion is fully coupled and detonated at a normally scaled depth, we find that the seismic yield is about 4 kt, with the uncertainties allowing a range from 2 to 8 kt.
The Shifting Nature of Work and Its Implications
Authors: Walton Michael J
Published: June 2016

Employment is a critical feature of modern society. The nature of employment not only determines the operation of the economy and economic and business prosperity but also determines the quality of individuals’ lives. In that respect, work is both an economic transaction and central to human life and dignity. There has been a seismic shift in how employment manifests in twenty-first-century Western economies. Rapid growth in non-standard forms of employment, and the corresponding decline of the standard employment contract, has resulted in a less stable and more fragmented labour market. Flexibility may benefit a worker who can operate successfully as a ‘free agent in a boundary-less workplace’. However, others may become stuck in enclaves, unable to access permanent work and having little bargaining power. This raises the prospect of the existence of a ‘dual labour market’, where workers are separated into primary and secondary markets. Those engaged in the primary market will have job security and opportunities for advancement, while those in secondary markets will become increasingly vulnerable. Regulatory systems based upon traditional models of employment are ill-equipped to deal with the challenges these developments pose for modern economies.
Comparative efficacy of telavancin and daptomycin in experimental
endocarditis due to multi-clonotype MRSA strains
Authors: Xiong Yan Q. , Abdelhady Wessam , Tang Chieh ‘Genna’ , Bayer Arnold S.
Published: June 2016

Background

MRSA strains of clonal complexes (CCs) 5, 8, 30 and 45 are leading causes of complicated endovascular infections associated with suboptimal clinical outcomes. Telavancin is a novel anti-MRSA agent that both inhibits bacterial cell wall synthesis and disrupts membranes by depolarization.

Methods

In this study, we compared the in vitro susceptibility and in vivo efficacy of telavancin versus daptomycin in an experimental rabbit infective endocarditis (IE) model caused by four MRSA strains representing each of the above CC types.

Results

All study strains were susceptible to telavancin (MICs of ≤0.12 mg/L) and daptomycin (MICs of ≤0.5 mg/L). In vitro time–kill analyses revealed that supra-MIC levels of telavancin were effective at preventing regrowth at 24 h of incubation. In the IE animal model for all CC types, treatment with telavancin produced significantly greater reductions in MRSA counts as compared with daptomycin-treated animals in all target tissues. Moreover, telavancin-treated animals had a significantly higher percentage of sterile tissue cultures versus daptomycin-treated animals (e.g. 78%–100% versus 0% sterile vegetations and 100% versus 0%–11% sterile kidneys and spleen, in the telavancin- and daptomycin-treated animals, respectively).

Conclusions

These results suggest that telavancin exhibits significantly greater efficacies versus daptomycin in treating experimental IE caused by MRSA clinical isolates across four common CC types.
Eligibility requirements for advanced health informatics certification
Authors: Gadd Cynthia S , Williamson Jeffrey J , Steen Elaine B , Andriole Katherine P , Delaney Connie , Gumpper Karl , LaVenture Martin , Rosendale Doug , Sittig Dean F , Thyvalikakath Thankam , Turner Peggy , Fridsma Douglas B
Published: June 2016

AMIA is leading the effort to strengthen the health informatics profession by creating an advanced health informatics certification (AHIC) for individuals whose informatics work directly impacts the practice of health care, public health, or personal health. The AMIA Board of Directors has endorsed a set of proposed AHIC eligibility requirements that will be presented to the future AHIC certifying entity for adoption. These requirements specifically establish who will be eligible to sit for the AHIC examination and more generally signal the depth and breadth of knowledge and experience expected from certified individuals. They also inform the development of the accreditation process and provide guidance to graduate health informatics programs as well as individuals interested in pursuing AHIC. AHIC eligibility will be determined by practice focus, education in primary field and health informatics, and significant health informatics experience.
Retracted: Environmental Conflict between Internally Displaced Persons and Host Communities in Iraq
Authors: Kaptan Kubilay
Published: June 2016

The environment, population and conflict thesis remains major to existing environment and security arguments. Throughout the 1990s, a huge increase in scholarship and policy focus was committed to unraveling the linkages amongst the three parameters. While it can very easily be asserted that both the analysis and policy communities have made substantial improvements, the academic results and policy instructions continue to be the subject matter of intense discussion. This article explores an assumptive method for the environment–conflict connection that views a collection of local parameters. The variable of resource management regimes is explored in more detail, illustrated by a case study from an Iraqi Internally Displaced Persons (IDPs) camp. The article finds theoretical and empirical evidence to support the view that participatory and inclusive resource management regimes may enable communities to construct resource-use conflicts in ways that help to prevent unproductive conflict. Such forms of governance can potentially be initiated in places where the state is failing to mitigate conflict through its own institutional resources. Thus, there may be an opportunity to respond to the ‘ingenuity gap’ that Homer-Dixon identifies as a key linkage between scarcity and conflict.
V346 Normae: first post-outburst observations of an FU Orionis star
Authors: Kraus S. , Caratti o Garatti A. , Garcia-Lopez R. , Kreplin A. , Aarnio A. , Monnier J. D. , Naylor T. , Weigelt G.
Published: June 2016

During their formation phase, stars gain most of their mass in violent episodic accretion events, such as observed in FU Orionis (FUor) and EXor stars. V346 Normae is a well-studied FUor that underwent a strong outburst beginning around 1980. Here, we report on photometric and spectroscopic observations, which show that the visual/near-infrared brightness has decreased dramatically between the 1990s and 2010 (ΔR ≈ 10.9 mag, ΔJ ≈ 7.8 mag and ΔK ≈ 5.8 mag). The spectral properties of this fading event cannot be explained by variable extinction alone, but indicate a drop in accretion rate by two to three orders of magnitude. This is the first time that a member of the FUor class has been observed to switch to a very low accretion phase. Remarkably, in the last few years (2011–2015) V346 Nor has brightened again at all near-infrared wavelengths, indicating the onset of a new outburst event. The observed behaviour might be consistent with the clustered luminosity bursts that have been predicted by recent gravitational instability and fragmentation models for the early stages of protostellar evolution. Given V346 Nor's unique characteristics (concerning outburst duration, repetition frequency and spectroscopic diagnostics), our results also highlight the need to revisit the FUor/EXor classification scheme.
Inset of Unilateral Dual Microvascular Breast Reconstruction Using Nonabdominal Free Tissue Transfer
Authors: Buescher Teresa M. , Andry Danielle , Brown Travis , Vargo James , Nazir Naiman , Andrews Brian T.
Published: June 2016

Background:

Large breasted patients are difficult to reconstruct using free tissue transfer after mastectomy when abdominal tissue is inadequate. For these, two unilateral free flaps may be required. This study reviews the authors’ experience using transverse upper gracilis and profunda artery perforator flaps.

Methods:

Through retrospective chart review, subjects were divided into three groups based on vascular anastomotic orientation: group 1, thoracodorsal and internal mammary; group 2, noncrossed internal mammary; and group 3, crossed internal mammary. Statistical comparison determined differences between groups for peri-operative “take-backs” and flap survival.

Results:

Twenty-one subjects underwent 42 free tissue transfers for unilateral breast reconstruction. Perioperative complications requiring return to the operating room occurred as follows for each group: group 1, two of four flaps (50 percent); group 2, two of two flaps (100 percent); and group 3, two of 36 flaps (5.5 percent). Long-term flap survival was as follows: group 1, three of four flaps (75 percent); group 2, zero of two flaps (0 percent); and group 3, 36 of 36 flaps (100 percent). Both the incidence of perioperative complications (p = 0.0011) and flap survival (p = 0.0008) were statistically significant in the three groups.

Conclusions:

Use of double free tissue transfer consisting of transverse upper gracilis or profunda artery perforator flaps is a feasible option for unilateral autologous breast reconstruction. In the authors’ experience, horizontal inset with crossed pedicles to the internal mammary system is the safest and most reliable technique for flap and pedicle inset.
Deep Pyriform Space: Anatomical Clarifications and Clinical Implications
Authors: Surek Christopher K. , Vargo James , Lamb Jerome
Published: June 2016

Background:

The purpose of this study was to define the anatomical boundaries, transformation in the aging face, and clinical implications of the Ristow space. The authors propose a title of deep pyriform space for anatomical continuity.

Methods:

The deep pyriform space was dissected in 12 hemifacial fresh cadaver dissections. Specimens were divided into three separate groups. For group 1, dimensions were measured and plaster molds were fashioned to evaluate shape and contour. For group 2, the space was injected percutaneously with dyed hyaluronic acid to examine proximity relationships to adjacent structures. For group 3, the space was pneumatized to evaluate its cephalic extension.

Results:

The average dimensions of the deep pyriform space are 1.1 × 0.9 cm. It is bounded medially by the depressor septi nasi and cradled laterally and superficially in a “half-moon” shape by the deep medial cheek fat and lip elevators. The angular artery courses on the roof of the space within a septum between the space and deep medial cheek fat. Pneumatization of the space traverses cephalic to the level of the tear trough ligament in a plane deep to the premaxillary space.

Conclusions:

The deep pyriform space is a midface cavity cradled by the pyriform aperture and deep medial cheek compartment. Bony recession of the maxilla with age predisposes this space for use as a potential area of deep volumization to support overlying cheek fat and draping lip elevators. The position of the angular artery in the roof of the space allows safe injection on the bone without concern for vascular injury.
Separation of Craniopagus Twins over the Past 20 Years: A Systematic Review of the Variables That Lead to Successful Separation
Authors: Harvey Donald J. , Totonchi Ali , Gosain Arun K.
Published: June 2016

Background:

Attempted separation of craniopagus twins has continued to be associated with devastating results since the first partially successful separation with one surviving twin in 1952. To understand the factors that contribute to successful separation in the modern era of neuroimaging and modern surgical techniques, the authors reviewed and analyzed cases reported since 1995.

Methods:

All reported cases of craniopagus twin separation attempts from 1995 to 2015 were identified using PubMed (n = 19). In addition, the Internet was searched for additional unreported separation attempts (n = 5). The peer-reviewed cases were used to build a categorical database containing information on each twin pair, including sex; date of birth; date of surgery; multiple- versus single-stage surgery; angular versus vertical conjoining; nature of shared cerebral venous system; and the presence of other comorbidities identified as cardiovascular, genitourinary, and craniofacial. The data were analyzed to find factors associated with successful separation (survival of both twins at postoperative day 30).

Results:

Vertical craniopagus is associated with successful separation (p < 0.001). No statistical significance was attributed to the nature of the shared cerebral venous drainage or the other variables examined. Multiple-stage operations and surgery before 12 months of age are associated with a trend toward statistical significance for successful separation.

Conclusions:

The authors’ analysis indicates that vertical craniopagus twins have the highest likelihood of successful separation. Additional factors possibly associated with successful separation include the nature of the shared sinus system, surgery at a young age, and the use of staged separations.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, V.
Appropriate and Effective Dosage of BMP-2 for the Ideal Regeneration of Calvarial Bone Defects in Beagles
Authors: Choi Jong Woo , Jeong Woo Shik , Yang Sung Jun , Park Eun Jung , Oh Tae Suk , Koh Kyung S.
Published: June 2016

Background:

Although bone morphogenetic protein-2 (BMP-2) is a potent growth factor, the appropriate and effective dosages for ideal bone formation according to defect size and type remain to be established. This study was designed to measure the effects of BMP-2 on calvarial defects in the beagle dog, by means of three-dimensional computed tomographic imaging.

Methods:

Eight beagles of equal age and weight were divided into one control and three experimental groups. After creating four circular 20-mm diameter defects, a BMP-2/tricalcium phosphate scaffolding mixture with concentrations of BMP-2 was introduced. The defect filling response was assessed until 16 weeks by three-dimensional computed tomograpy for the thickness, area, and density of the regenerating bone.

Results:

Statistically significant responses to BMP-2 were observed. The mean thicknesses of the regenerated bone were 1.6 mm for the control group and 1.6, 2.1, and 2.8 mm for 10, 50, and 200 µg/ml, respectively. As the original mean thickness of the calvarial bone in the beagles was 2.0 mm, a 50-µg quantity of BMP-2 proved to be ideal for 2-cm calvarial defects. The original surface area of the defect created was 314 mm2. The mean surface areas of the regenerated bone were 181.94 mm2 for the control group, and 237, 276, and 288 mm2 for 10, 50, and 200 µg/ml.

Conclusions:

BMP-2 promotes anatomically significant bone regeneration in critical-size cranial defects in this model, with an optimal dose-response at 50 µg/ml and without hyperosteogenesis or hypo-osteogenesis.
Can the Babysitter Procedure Improve Nerve Regeneration and Denervated Muscle Atrophy in the Treatment of Peripheral Nerve Injury?
Authors: Liu Hai-Fei , Chen Zeng-Gan , Lineaweaver William C. , Zhang Feng
Published: June 2016

Background:

The authors evaluated the long-term efficacy of the “babysitter” procedure in improving nerve regeneration and denervated muscle atrophy for peripheral nerve repair.

Methods:

Eighty Lewis rats were allocated equally into four groups. The peroneal nerves of all animals were divided. In group A, the peroneal nerve stumps were anchored into adjacent muscles. Rats in group B underwent end-to-end neurorrhaphy. Rats in group C underwent end-to-side neurorrhaphy of the distal peroneal nerve stump to an epineurial window on the tibial nerve. Rats in group D underwent end-to-side neurorrhaphy of the distal stump to the tibial nerve with 40 percent neurectomy. After 8 weeks, end-to-end neurorrhaphy of the peroneal nerve stumps was performed in group A, C, and D during a second-stage procedure. Electrophysiology, myelinated fiber counts, muscle force and weight, and muscle histomorphometry were analyzed at 4, 8, 12, and 24 weeks postoperatively.

Results:

At 4 weeks, the end-to-end group showed predominant advantages in nerve regeneration and muscle preservation. No differences were observed in the latency delaying rate, tetanic tension, myelinated fiber number, or muscle weight between groups B and D by 24 weeks (p > 0.05). At 24 weeks, the results revealed superior latency delaying rate, myelinated axon regeneration, and size of muscle fibers in group D as compared with group C.

Conclusions:

Peripheral nerve repair with an initial motor nerve babysitter with 40 percent neurectomy of the donor nerve can achieve high efficacy in functional and structural recovery of the recipient system. Nerve babysitter by motor nerve with an epineural window was less effective.
Total Face, Eyelids, Ears, Scalp, and Skeletal Subunit Transplant: A Reconstructive Solution for the Full Face and Total Scalp Burn
Authors: Sosin Michael , Ceradini Daniel J. , Levine Jamie P. , Hazen Alexes , Staffenberg David A. , Saadeh Pierre B. , Flores Roberto L. , Sweeney Nicole G. , Bernstein G. Leslie , Rodriguez Eduardo D.
Published: June 2016

Background:

Reconstruction of extensive facial and scalp burns can be increasingly challenging, especially in patients that have undergone multiple procedures with less than ideal outcomes resulting in restricting neck and oral contractures, eyelid dysfunction, and suboptimal aesthetic appearance.

Methods:

To establish a reconstructive solution for this challenging deformity, a multidisciplinary team was assembled to develop the foundation to a facial vascularized composite allotransplantation program. The strategy of developing and executing a clinical transplant was derived on the basis of fostering a cohesive and supportive institutional clinical environment, implementing computer software and advanced technology, establishing a cadaveric transplant model, performing a research facial procurement, and selecting an optimal candidate with the aforementioned burn defect who was well informed and had the desire to undergo face transplantation.

Results:

Approval from the institutional review board and organ procurement organization enabled our face transplant team to successfully perform a total face, eyelids, ears, scalp, and skeletal subunit transplant in a 41-year-old man with a full face and total scalp burn.

Conclusions:

The culmination of knowledge attained from previous experiences continues to influence the progression of facial vascularized composite allotransplantation. This surgical endeavor methodically and effectively synchronized the fundamental principles of aesthetic, craniofacial, and microvascular surgery to restore appearance and function to a patient suffering from failed conventional surgery for full face and total scalp burns. This procedure represents the most extensive soft-tissue clinical face transplant performed to date.

CLINICAL QUESTION/LEVEL OF EVIDEMCE:

Therapeutic, V.
Looking Beyond the Cascade of HIV Care to End the AIDS Epidemic: Estimation of the Time Interval From HIV Infection to Viral Suppression
Authors: Supervie Virginie , Marty Lise , Lacombe Jean-Marc , Dray-Spira Rosemary , Costagliola Dominique ,   the FHDH-ANRS CO4 study group
Published: June 2016

Background:

Ensuring early universal access to HIV treatment is critical to reach the end of AIDS. The cascade of HIV care has become a critical metric to assess the coverage of treatment and viral suppression, but it does not provide any information on the elapsed times between becoming HIV-infected and reaching viral suppression.

Methods:

We estimated the cascade of care, the distribution of times between steps of the care continuum, in France, in 2010, at the national level, overall and by HIV exposure groups, using statistical modelling and large datasets: the national HIV surveillance system, the general social insurance scheme, and the French Hospital Database on HIV.

Results:

We found that the overall rate of viral suppression was high, with an estimated value of 52% (95% confidence interval: 49 to 54). However, the time intervals from HIV infection to viral suppression were long; overall, the median value was 6.1 years (inter quartile range: 3.6–9.2), and it ranged from ∼5.6 years among men who have sex with men and heterosexual women to 9.6 years among injection drug users. Time lost in achieving viral suppression was mainly due to delays in HIV testing (overall median of 3.4 years), except for injection drug users where it was also due to delayed care entry once diagnosed (∼1 year in median versus <1 month for other groups).

Conclusions:

High viral suppression rate can hide large gaps between time of HIV infection and time of viral suppression. Estimates of the flow-time between steps of the care continuum should become priority indicators to identify these gaps and monitor whether interventions are successful in closing them.
From cineradiography to biorobots: an approach for designing robots to emulate and study animal locomotion
Authors: Karakasiliotis K. , Thandiackal R. , Melo K. , Horvat T. , Mahabadi N. K. , Tsitkov S. , Cabelguen J. M. , Ijspeert A. J.
Published: June 2016

Robots are increasingly used as scientific tools to investigate animal locomotion. However, designing a robot that properly emulates the kinematic and dynamic properties of an animal is difficult because of the complexity of musculoskeletal systems and the limitations of current robotics technology. Here, we propose a design process that combines high-speed cineradiography, optimization, dynamic scaling, three-dimensional printing, high-end servomotors and a tailored dry-suit to construct Pleurobot: a salamander-like robot that closely mimics its biological counterpart,Pleurodeles waltl. Our previous robots helped us test and confirm hypotheses on the interaction between the locomotor neuronal networks of the limbs and the spine to generate basic swimming and walking gaits. With Pleurobot, we demonstrate a design process that will enable studies of richer motor skills in salamanders. In particular, we are interested in how these richer motor skills can be obtained by extending our spinal cord models with the addition of more descending pathways and more detailed limb central pattern generator networks. Pleurobot is a dynamically scaled amphibious salamander robot with a large number of actuated degrees of freedom (DOFs: 27 in total). Because of our design process, the robot can capture most of the animal's DOFs and range of motion, especially at the limbs. We demonstrate the robot's abilities by imposing raw kinematic data, extracted from X-ray videos, to the robot's joints for basic locomotor behaviours in water and on land. The robot closely matches the behaviour of the animal in terms of relative forward speeds and lateral displacements. Ground reaction forces during walking also resemble those of the animal. Based on our results, we anticipate that future studies on richer motor skills in salamanders will highly benefit from Pleurobot's design.
Recovery from bleaching is mediated by threshold densities of background thermo-tolerant symbiont types in a reef-building coral
Authors: Bay Line K. , Doyle Jason , Logan Murray , Berkelmans Ray
Published: June 2016

Sensitive molecular analyses show that most corals host a complement ofSymbiodiniumgenotypes that includes thermo-tolerant types in low abundance. While tolerant symbiont types are hypothesized to facilitate tolerance to temperature and recovery from bleaching, empirical data on their distribution and relative abundance in corals under ambient and stress conditions are still rare. We quantified visual bleaching and mortality of coral hosts, along with relative abundance of C- and D-typeSymbiodiniumcells in 82Acropora milleporacolonies from three locations on the Great Barrier Reef transplanted to a central inshore site over a 13 month period. Our analyses reveal dynamic change in symbiont associations within colonies and among populations over time. Coral bleaching and declines in C- but not D-type symbionts were observed in transplanted corals. Survival and recovery of 25% of corals from one population was associated with either initial D-dominance or an increase in D-type symbionts that could be predicted by a minimum pre-stress D : C ratio of 0.003. One-third of corals from this population became D dominated at the bleached stage despite no initial detection of this symbiont type, but failed to recover and died in mid to late summer. These results provide a predictive threshold minimum density of background D-type symbionts inA. millepora,above which survival following extreme thermal stress is increased.
Superhydrophobicity of the gecko toe pad: biological optimization versus laboratory maximization
Authors: Stark Alyssa Y. , Subarajan Shairani , Jain Dharamdeep , Niewiarowski Peter H. , Dhinojwala Ali
Published: June 2016

While many gecko-inspired hierarchically structured surfaces perform as well as or better than the natural adhesive system, these designs often fail to function across a variety of contexts. For example, the gecko can adhere to rough, wet and dirty surfaces; however, most synthetic mimics cannot maintain function when faced with a similar situation. The solution to this problem lies in a more thorough investigation of the natural system. Here, we review the adhesive system of the gecko toe pad, as well as the far less-well-studied anti-adhesive system that results from the chemistry and structure of the toe pad (superhydrophobicity). This paradoxical relationship serves as motivation to study functional optimization at the system level. As an example, we experimentally investigate the role of surface lipids in adhesion and anti-adhesion, and find a clear performance trade-off related to shear adhesion in air on a hydrophilic surface. This represents the first direct investigation of the role of surface lipids in gecko adhesion and anti-adhesion, and supports the argument that a system-level approach is necessary to elucidate optimization in biological systems. Without such an approach, bioinspired designs will be limited in functionality and context, especially compared to the natural systems they mimic.

This article is part of the themed issue ‘Bioinspired hierarchically structured surfaces for green science’.