bluuebunny/crossref_metadata_2025 huggingface dataset:
Adding Satellite Rods to Standard Two-rod Construct With the Use of Duet Screws
Authors: Zhu Ze-zhang , Chen Xi , Qiu Yong , Chen Zhong-hui , Li Song , Xu Liang , Sun Xu
Published: November 2017

Study Design.

A retrospective matched-cohort comparative study.

Objective.

The aim of this study was to compare the surgical results after the use of duet screw based satellite rods and bilateral satellite rods (S-RC) versus a standard two-rod construct (2-RC) across osteotomy sites in a matched cohort with Scheuermann kyphosis (SK).

Summary of Background Data.

Multiple Ponte osteotomies are frequently employed to correct SK via a posterior-only approach, with a 2-RC across the osteotomy sites. Whereas, correction rate and junction problems remain as the major concerns.

Methods.

This study reviewed a consecutive series of patients with SK who had undergone posterior-only correction with multilevel Ponte osteotomy between 2009 and 2014 and had been followed over 24 months. Twenty-two patients receiving placement with an S-RC with the use of duet screws were identified and closely matched with 22 patients with a 2-RC in terms of age, apex, and magnitude of kyphosis. Comparisons were made with regards to deformity magnitude, correction results, complications, and clinical outcomes between the two groups.

Results.

No significant difference was found between groups in preoperative patient's factors (age, gender, apex, magnitude of kyphosis, and SRS-22 scores) and surgical factors (blood loss, operation time, osteotomy levels, and fused levels). Compared with the 2-RC group, the S-RC group had higher correction rate (55.4% ± 7.5% vs. 46.2% ± 5.1%, P < 0.001), less correction loss (1.0 ± 0.8° vs. 2.4 ± 1.4°, P < 0.001) during the follow-up, and higher improvement of back pain as well (P < 0.05). None were detected with pseudarthrosis or implant failure in either group, but proximal junctional kyphosis was less frequently seen in S-RC group (1 of 22) than 2-RC group (7 of 22) (P < 0.05).

Conclusion.

As a safe method, use of S-RC is effective in providing increased kyphotic correction across multiple Ponte osteotomy levels, and improving patient-reported outcomes of management satisfaction and back pain. The biomechanical benefits of stress dispersion, coupled with increased stability and weight bearing ability, make it a powerful technique preventing correction loss and proximal junctional kyphosis.

Level of Evidence: 3
Common Variant of POC5 Is Associated With the Susceptibility of Adolescent Idiopathic Scoliosis
Authors: Xu Leilei , Sheng Fei , Xia Chao , Li Yetian , Feng Zhenhua , Qiu Yong , Zhu Zezhang
Published: November 2017

Study Design.

A case-control study.

Objective.

To validate the relationship between POC5 and adolescent idiopathic scoliosis (AIS) in the Chinese patients and to further investigate the functional role of POC5.

Summary of Background Data.

Three rare functional variants in the POC5 were recently reported to be strongly associated with the disease in a large family with multiple members affected with idiopathic scoliosis. To our knowledge, the association between the mutations of POC5 and AIS remains undetermined in the Chinese population.

Methods.

Single nucleotide variants c.1336G>A, c.1286C>T, and c.1363G>C of POC5 were genotyped in 2432 patients with AIS and 2292 healthy controls using multiple ligase detection reactions. Common variants covering POC5 gene were genotyped in 1446 patients and 2080 controls. The mRNA expression of POC5 was determined in the paraspinal muscles collected from 98 patients and 28 controls. The Student t test was used to compare mRNA expression level between the patients and the controls. In addition, the POC5 expression was compared among different genotypes of the remarkably associated single nucleotide polymorphism (SNP) with analysis of variance test.

Results.

There was no case of mutation for the three reported variants of POC5. SNP rs6892146 was observed to have significantly different distribution of minor allele frequency in the two group (0.485 vs. 0.446, P = 0.004). The mRNA expression of POC5 was 1.5-fold higher in patients than in the controls (0.00012 ± 0.00009 vs. 0.00008 ± 0.00006, P = 0.02). Patients with genotype GG have a significantly increased expression of POC5 than those with CC (0.00014 ± 0.00007 vs. 0.00009 ± 0.00007, P = 0.03).

Conclusion.

Common variant rs6892146 of POC5 is associated with the development of AIS in the Chinese population. Targeted regional sequencing of POC5 may help identify novel mutations associated with AIS.

Level of Evidence: 4
Tranexamic Acid Decreases Visible and Hidden Blood Loss Without Affecting Prethrombotic State Molecular Markers in Transforaminal Thoracic Interbody Fusion for Treatment of Thoracolumbar Fracture-Dislocation
Authors: Wang Wentao , Duan Kun , Ma Minjie , Jiang Yong , Liu Tuanjiang , Liu Jijun , Hao Dingjun
Published: November 2017

Study Design.

A randomized, double-blind, placebo-controlled clinical trial.

Objective.

To evaluate the efficacy and safety of tranexamic acid (TXA) administered during the surgical correction of thoracolumbar fracture–dislocation.

Summary of Background Data.

Thoracolumbar fracture-dislocation surgery is generally associated with substantial blood loss and a high risk of deep vein thrombosis. TXA has been shown to improve hemostasis in surgical procedures.

Methods.

We investigated 80 patients with thoracolumbar fracture-dislocation who underwent transforaminal thoracic interbody fusion between March 2014 and December 2016. The patients were randomized into the TXA (n = 39) and Placebo (n = 41) groups, according to whether they did or did not receive pre- and intraoperative TXA treatment. The two groups were compared for demographic characteristics as well as pre- and postoperative levels of prethrombosis-state molecular markers and visible and hidden blood loss volumes. Additionally, the prevalence of TXA-related complications was determined.

Results.

The two groups did not differ significantly in demographic characteristics. The visible blood loss (intra- and postoperative bleeding during the first 24 h), hidden blood loss, and true total blood loss during surgery in the TXA group were significantly lower than those in the Placebo group (835 ± 180.3 mL, 351 ± 82.3 mL, 1385 ± 102.3 mL vs. 1155 ± 175.3 mL, 564 ± 170.5 mL, 1683 ± 121.0 mL, respectively; P < 0.01). Furthermore, the levels of the prethrombosis-state molecular markers GMP-140, fibrinogen, fibrin degradation products, and D-dimer were higher in the TXA group than in the Placebo group, although the differences were not significant (P > 0.05). No significant intergroup differences were noted in the prevalence of deep venous thrombosis and pulmonary embolus during the study period.

Conclusion.

TXA significantly reduced visible and hidden blood loss without affecting the prethrombosis-state molecular markers in transforaminal thoracic interbody fusion or causing any notable adverse effects.

Level of Evidence: 3
Craniofacial Reconstruction by a Cost-Efficient Template-Based Process Using 3D Printing
Authors: Msallem Bilal , Beiglboeck Fabian , Honigmann Philipp , Jaquiéry Claude , Thieringer Florian
Published: November 2017

Craniofacial defects often result in aesthetic and functional deficits, which affect the patient’s psyche and wellbeing. Patient-specific implants remain the optimal solution, but their use is limited or impractical due to their high costs. This article describes a fast and cost-efficient workflow of in-house manufactured patient-specific implants for craniofacial reconstruction and cranioplasty. As a proof of concept, we present a case of reconstruction of a craniofacial defect with involvement of the supraorbital rim. The following hybrid manufacturing process combines additive manufacturing with silicone molding and an intraoperative, manual fabrication process. A computer-aided design template is 3D printed from thermoplastics by a fused deposition modeling 3D printer and then silicone molded manually. After sterilization of the patient-specific mold, it is used intraoperatively to produce an implant from polymethylmethacrylate. Due to the combination of these 2 straightforward processes, the procedure can be kept very simple, and no advanced equipment is needed, resulting in minimal financial expenses. The whole fabrication of the mold is performed within approximately 2 hours depending on the template’s size and volume. This reliable technique is easy to adopt and suitable for every health facility, especially those with limited financial resources in less privileged countries, enabling many more patients to profit from patient-specific treatment.
Meibomian Glands and Ocular Surface Changes After Closure of Meibomian Gland Orifices in Rabbits
Authors: Eom Youngsub , Han Ji Yun , Kang Boram , Hwang Ho Sik , Lee Hyung Keun , Kim Hyo Myung , Song Jong Suk
Published: November 2017

Purpose:

To investigate changes in the corneal surface, tear film, and meibomian glands after meibomian gland orifice closure.

Methods:

Seventy-two eyes of 36 rabbits were used. In the study group (n = 36), the meibomian gland orifices of both upper and lower eyelids in the right eyes were electrosurgically coagulated. The 36 untreated left eyes were used as controls. Corneal wetting properties were measured 1, 3, 7, and 14 days after coagulation. The eyelid sections were stained with anti-cytokeratin (CK)1, CK5, and CK6 antibody 8 weeks after coagulation. The area of the secretory acini around one meibomian gland duct was measured, and meibography of rabbits was performed 8 weeks after meibomian gland orifice closure.

Results:

Three days after coagulation, the corneal wetting property was decreased compared with controls. The meibomian gland ducts gradually dilated in the study group over time. The epithelium of the central ducts in both groups was stained with CK5 and CK6, but not CK1. Although the mean area of the secretory acini in the study group (0.10 ± 0.04 mm2) was significantly smaller than that of the control group (0.18 ± 0.04; P = 0.004), meibography showed normal morphology in both study and control groups.

Conclusions:

Meibomian gland orifice closure reduced corneal wetting property and induced meibomian gland duct dilation accompanied by shrinkage of secretory acini. Meibography could not detect early changes in the meibomian gland after closure of the orifice. Therefore, when the orifice is obstructed, more active treatments are needed before structural changes occur.
Invasive Haemophilus influenzae Serotype a Infection in Children
Authors: Plumb Ian D. , Lecy K. Danielle , Singleton Rosalyn , Engel Michael C. , Hirschfeld Matthew , Keck James W. , Klejka Joseph , Rudolph Karen M. , Hennessy Thomas W. , Bruce Michael G.
Published: November 2017

Background:

Invasive infections from Haemophilus influenzae serotype a (Hia) have been reported with increasing frequency, especially among indigenous populations. However, there are limited population-based studies of clinical severity. We studied invasive Hia infections in Alaska to determine clinical characteristics, mortality and sequelae.

Methods:

We defined an invasive Hia infection as the first detection of Hia from a usually sterile site in a child <10 years of age from Alaska. We identified cases using the Alaska Invasive Bacterial Diseases Surveillance System and reviewed medical charts up to 2 years after reported illness.

Results:

We identified invasive Hia infections in 36 children, 28 (78%) <1 year old, 34 (94%) living in an Alaskan village and 25 (69%) without documented underlying illness. Overlapping clinical presentations included meningitis in 15 children (42%); bacteremia and pneumonia in 10 children (28%); and bone, joint or soft tissue infections in 10 children (22%). In 4 other children, no source of invasive infection was identified. Intensive care was provided for 11 children (31%); 12 children (33%) required surgical intervention. One year after infection, 4 children (11%) had died from Hia, and 5 children (14%) had ongoing neurologic sequelae.

Conclusions:

Invasive Hia infections in Alaska occurred predominantly in Alaska Native infants in rural communities. Although one-third of children had preexisting conditions, most cases occurred without known comorbidity. Clinical syndromes were frequently severe. One year after infection, 1 in 4 children had either died or had neurologic sequelae. An effective vaccine would prevent significant morbidity and mortality in affected populations.
Disseminated Cryptococcosis With Severe Increased Intracranial Pressure Complicated With Cranial Nerve Palsy in a Child
Authors: Aldemir Kocabaş Bilge , Emin Parlak Mehmet , Özhak Baysan Betil , Karaali Kamil , Bingöl Ayşen , Haspolat Şenay
Published: November 2017

Cryptococcosis is less common in children than in adults but remains an important cause of pneumonia and meningoencephalitis in both immunocompromised and immunocompetent patients. Intracranial hypertension commonly complicates cryptococcal meningitis and may cause significant visual and neurologic morbidity and mortality. Early and aggressive management of intracranial hypertension in accordance with established guidelines reduces the risk of long-term complications and death. In this case report, we present a 12-year-old girl with cryptococcal meningitis, pneumonitis and dermatitis complicated with cranial nerve palsy and loss of vision. She was successfully treated with serial cerebrospinal fluid drainage, antifungal and interferon gamma therapy.
Defining Study Outcomes That Better Reflect Individual Response to Treatment
Authors: Angelidou Konstantia , Palumbo Paul , Lindsey Jane , Violary Avy , Archary Moherndran , Barlow Linda , Claggett Brian , Hughes Michael , Wei Lee-Jen
Published: November 2017

Background:

Most clinical trials comparing treatments evaluate the separate effects on each of several efficacy and toxicity outcomes. However, population-averaged summary measures of treatment differences may not accurately reflect individual responses to treatment, and drawing conclusions about which treatment is “best” is straightforward if one treatment is superior across all outcomes, but challenging when this is not the case.

Methods:

We created a study outcome based on expert opinion, which captures the risk/benefit profile of response to a treatment. Treatments were compared using this ordered outcome with standard statistical techniques. To illustrate the approach, we used as an example a study designed to evaluate initial antiretroviral therapy (ART) in human immunodeficiency virus-1–infected infants, in which results were contradictory across the study’s primary and secondary efficacy and toxicity outcomes. The proposed risk/benefit outcome was evaluated retrospectively in each participant.

Results:

In the International Maternal Pediatric Adolescent AIDS Clinical Trials P1060 study, one treatment regimen (lopinavir/ritonavir-based ART) was superior to the other (nevirapine-based ART) in reducing viral load (primary outcome) but inferior for immunologic and growth outcomes (important secondary outcomes in resource-limited settings). Treatment comparisons using the risk/benefit outcome indicated that the lopinavir/ritonavir-based ART regimen had a higher proportion of participants with the best overall response to treatment. Comparisons focusing on individual-level responses for the secondary outcomes also favored lopinavir/ritonavir-based ART, results that differed from the original population-averaged analyses ones.

Conclusions:

Designing studies prospectively using risk/benefit outcomes focusing on an individual’s responses to treatment more closely matches the needs of clinicians making decisions about how best to treat patients in clinical settings.
Increasing Linezolid-resistant Enterococcus in a Children’s Hospital
Authors: Bagga Bindiya , Buckingham Steve , Arnold Sandra , Nesbitt Amanda , Guimera Don , Lee Kelley
Published: November 2017

We report a reduction in susceptibility to linezolid among Enterococcus isolates (98% in 2007 vs. 46% in 2014) in parallel with a 5-fold increase in linezolid use. A direct association could not be established as the majority of patients with linezolid nonsusceptible isolates did not have prior linezolid exposure. Nosocomial transmission of the nonsusceptible isolates could certainly have contributed.
Rotavirus Genotypes Circulating in Brazil Before and After the National Rotavirus Vaccine Program
Authors: Santos Victor S. , Nóbrega Flávia A. , Soares Mariana W. S. , Moreira Renan D. , Cuevas Luis E. , Gurgel Ricardo Q.
Published: November 2017

Background:

Rotavirus vaccines created the opportunity to control diarrhea in children. We describe the rotavirus genotypes before and after the rotavirus vaccine introduction in Brazil.

Methods:

We reviewed the distribution of rotavirus genotypes in Brazil before and after vaccine introduction by searching publication.

Results:

Eighty-six studies reported 6884 (15.2%) rotavirus episodes among 45,305 children. Rotavirus caused 22.4% and 11.6% of cases before and after vaccine introduction. G1P[8], G9P[8] and G2P[4] heterotypic strains were most common before and after vaccine introduction.

Conclusions:

The vaccines may have selected heterotypic strains in this highly vaccinated population.
The Boy in the Bubble and the Baby With the Berlin Heart: The Dangers of “Bridge to Decision” in Pediatric Mechanical Circulatory Support
Authors: Hollander Seth A. , Hollander Ethan J.
Published: November 2017

On the day of his birth in 1971, David Vetter was “temporarily” placed in a sterile isolator to wait for a bone marrow donor who would cure his Severe Combined Immunodeficiency Syndrome. After enduring 12 years in isolation, David, now known to the world as “The Boy in the Bubble”, received a bone marrow transplant from his unmatched sister and died 4 months later. Like Severe Combined Immunodeficiency Syndrome, pediatric heart failure is a rare and life-threatening condition for which organ transplantation is often the only option for survival. Nearly 15 years ago, the Berlin Heart EXCOR ventricular assist device was developed, as the isolator was for David, to be a bridge to transplantation for infants and children with unstable heart failure. Yet, when symptoms progress faster than the patient’s suitability for transplant can be evaluated, this device may be implanted as a “bridge-to-decision” while a transplant evaluation is completed. Therein lies the potential for history to repeat itself. As biomedical science carries us ever forward in our ability to sustain life, we must always bear in mind that the miraculous EXCOR must not be a machine that simply sustains the circulation. It must be, and always remain, a bridge to somewhere.
Comparison of Psychiatric Symptoms in Patients With Obstructive Sleep Apnea, Simple Snoring, and Normal Controls
Authors: Kang Jae Myeong , Cho Seong-Jin , Lee Yu Jin , Kim Ji-Eun , Shin Seung-Heon , Park Kee Hyung , Kim Seon Tae , Kang Seung-Gul
Published: November 2017

Objective

Patients with sleep-related breathing disorders are known to have more severe psychiatric symptoms than good sleepers. The aim of this study was to compare the psychiatric symptoms of participants with obstructive sleep apnea (OSA), those with simple snoring (SS), and normal controls (NC).

Methods

A total of 386 participants (260 with OSA, 75 with SS, and 51 NC) completed self-report questionnaires including the Symptoms Checklist 90-Revised and underwent nocturnal polysomnography. The scores of nine primary symptom dimensions and three global distress indices of the Symptoms Checklist 90-Revised were compared among the three groups, adjusting for age, sex, and body mass index.

Results

Participants with suspected OSA (OSA + SS) reported more severe psychiatric symptoms than the NC group. Compared with the participants with OSA, those with SS manifested more severe obsessive-compulsive (1.4 (1.0) versus 1.1 (0.7), p = .008) and depressive (1.2 (1.2) versus 0.8 (0.8), p = .031) symptoms and higher Global Severity Index (1.0 (0.9) versus 0.7 (0.6), p = .039) and Positive Symptom Distress Index (2.0 (0.8) versus 1.7 (0.6), p = .009). Only higher Pittsburgh Sleep Quality Index values predicted higher Global Severity Index (B = 0.11, p = .041) and Positive Symptom Distress Index (B = 0.46, p = .007) in suspected OSA participants.

Conclusions

This study found that individuals with suspected OSA experienced more severe psychiatric symptoms than NCs and that psychiatric symptoms were more severe in the SS group than in the OSA group. The psychiatric symptoms of suspected OSA patients were associated with subjective sleep quality rather than with the apnea-hypopnea index.
Superficial Slow Rhythms Integrate Cortical Processing in Humans
Authors: Halgren Mila , Fabo Daniel , Ulbert István , Madsen Joseph R. , Eröss Lorand , Doyle Werner K. , Devinsky Orrin , Schomer Donald , Cash Sydney S. , Halgren Eric
Published: November 2017

The neocortex is composed of six anatomically and physiologically specialized layers. It has been proposed that integration of activity across cortical areas is mediated anatomically by associative connections terminating in superficial layers, and physiologically by slow cortical rhythms. However, the means through which neocortical anatomy and physiology interact to coordinate neural activity remains obscure. Using laminar microelectrode arrays in 19 human participants, we found that most EEG activity is below 10-Hz (delta/theta) and generated by superficial cortical layers during both wakefulness and sleep. Cortical surface grid, grid-laminar, and dual-laminar recordings demonstrate that these slow rhythms are synchronous within upper layers across broad cortical areas. The phase of this superficial slow activity is reset by infrequent stimuli and coupled to the amplitude of faster oscillations and neuronal firing across all layers. These findings support a primary role of superficial slow rhythms in generating the EEG and integrating cortical activity.
Recording neural activity in unrestrained animals with 3D tracking two photon microscopy
Authors: Karagyozov Doycho , Mihovilovic Skanata Mirna , Lesar Amanda , Gershow Marc
Published: November 2017

Optical recordings of neural activity in behaving animals can reveal the neural correlates of decision making, but such recordings are compromised by brain motion that often accompanies behavior. Two-photon point scanning microscopy is especially sensitive to motion artifacts, and to date, two-photon recording of activity has required rigid mechanical coupling between the brain and microscope. To overcome these difficulties, we developed a two-photon tracking microscope with extremely low latency (360 μs) feedback implemented in hardware. We maintained continuous focus on neurons moving with velocities of 3 mm/s and accelerations of 1 m/s2 both in-plane and axially, allowing high-bandwidth measurements with modest excitation power. We recorded from motor- and inter-neurons in unrestrained freely behaving fruit fly larvae, correlating neural activity with stimulus presentation and behavioral outputs. Our technique can be extended to stabilize recordings in a variety of moving substrates.
Determinants of target prioritization and regulatory hierarchy for the bacterial small RNA SgrS
Authors: Bobrovskyy Maksym , Frandsen Jane K. , Zhang Jichuan , Poddar Anustup , Azam Muhammad S. , Henkin Tina M. , Ha Taekjip , Vanderpool Carin K.
Published: November 2017

The mechanisms by which small RNA (sRNA) regulators select and prioritize target mRNAs remain poorly understood, but serve to promote efficient responses to environmental cues and stresses. We sought to uncover mechanisms that establish regulatory hierarchy for a model sRNA, SgrS, found in enteric bacteria and produced under conditions of metabolic stress when sugar transport and metabolism are unbalanced. SgrS post-transcriptionally controls a nine-gene regulon to restore growth and homeostasis under stress conditions. Anin vivoreporter system was used to quantify SgrS-dependent regulation of target genes and established that SgrS exhibits a clear preference for certain targets, and regulates those targets efficiently even at low SgrS levels. Higher SgrS concentrations are required to regulate other targets. The position of targets in the regulatory hierarchy is not well-correlated with the predicted thermodynamic stability of SgrS-mRNA interactions or the SgrS-mRNA binding affinity as measuredin vitro. Detailed analyses of SgrS interaction withasdmRNA demonstrate that SgrS binds cooperatively to two sites and remodelsasdmRNA secondary structure. SgrS binding at both sites increases the efficiency ofasdmRNA regulation compared to mutants that have only a single SgrS binding site. Our results suggest that sRNA selection of target mRNAs and regulatory hierarchy are influenced by several molecular features. The sRNA-mRNA interaction, including the number and position of sRNA binding sites on the mRNA and cofactors like the RNA chaperone Hfq, seem to tune the efficiency of regulation of specific mRNA targets.

IMPORTANCE

To survive, bacteria must respond rapidly to stress and simultaneously maintain metabolic homeostasis. The small RNA (sRNA) SgrS mediates the response to stress arising from imbalanced sugar transport and metabolism. To coordinate the stress response, SgrS regulates genes involved in sugar uptake and metabolism. Intrinsic properties of sRNAs such as SgrS allow them to regulate extensive networks of genes. To date, sRNA regulation of targets has largely been studied in the context of “one sRNA-one target”, and little is known about coordination of multi-gene regulons and sRNA regulatory network structure. Here, we explore the molecular basis for regulatory hierarchy in sRNA regulons. Our results reveal a complex interplay of factors that influence the outcome of sRNA regulation. The number and location of sRNA binding sites on mRNA targets and the participation of an RNA chaperone dictate prioritized regulation of targets to promote an efficient response to stress.
Binocular disparity can augment the capacity of vision without affecting subjective experience of depth
Authors: Railo Henry , Saastamoinen Joni , Kylmälä Sipi , Peltola Aapo
Published: November 2017

Binocular disparity results in a tangible subjective experience of three-dimensional world, but whether disparity also augments objective perceptual performance remains debated. We hypothesized that the improved coding of depth enabled by binocular disparity allows participants to individuate more object at a glance as the objects can be more efficiently differentiated from each other and the background. We asked participants to enumerate objects in briefly presented naturalistic (Experiment 1) and artificial (Experiment 2) scenes in immersive virtual reality. This type of enumeration task yields well-documented capacity limits where up to 3-4 items can be enumerated rapidly and accurately, known as subitizing. Our results show that although binocular disparity did not yield a large general improvement in enumeration accuracy or reaction times, it improved participants’ ability to process the items right after the limit of perceptual capacity. Binocular disparity also sped-up response times by 27 ms on average when artificial stimuli (cubes) were used. Interestingly, the influence of disparity on subjectively experienced depth revealed a clearly different pattern than the influence of disparity on objective performance. This suggests that the functional and subjective sides of stereopsis can be dissociated. Altogether our results suggest that binocular disparity may increase the number of items the visual system can simultaneously process. This may help animals to better resolve and track objects in complex, cluttered visual environments.
Protein crystals IR laser ablated from aqueous solution at high speed retain their diffractive properties: applications in high-speed serial crystallography
Authors: Schulz Eike C. , Kaub Johannes , Busse Frederik , Mehrabi Pedram , Müller-Werkmeister Henrike M. , Pai Emil F. , Robertson Wesley D. , Miller R. J. Dwayne
Published: November 2017

In order to utilize the high repetition rates now available at X-ray free-electron laser sources for serial crystallography, methods must be developed to softly deliver large numbers of individual microcrystals at high repetition rates and high speeds. Picosecond infrared laser (PIRL) pulses, operating under desorption by impulsive vibrational excitation (DIVE) conditions, selectively excite the OH vibrational stretch of water to directly propel the excited volume at high speed with minimized heating effects, nucleation formation or cavitation-induced shock waves, leaving the analytes intact and undamaged. The soft nature and laser-based sampling flexibility provided by the technique make the PIRL system an interesting crystal delivery approach for serial crystallography. This paper demonstrates that protein crystals extracted directly from aqueous buffer solution via PIRL-DIVE ablation retain their diffractive properties and can be usefully exploited for structure determination at synchrotron sources. The remaining steps to implement the technology for high-speed serial femtosecond crystallography, such as single-crystal localization, high-speed sampling and synchronization, are described. This proof-of-principle experiment demonstrates the viability of a new laser-based high-speed crystal delivery system without the need for liquid-jet injectors or fixed-target mounting solutions.
Full elastic strain tensor determination at the phase scale in a powder metallurgy nickel-based superalloy using X-ray Laue microdiffraction
Authors: Altinkurt Gader , Fèvre Mathieu , Robach Odile , Micha Jean-Sébastien , Geandier Guillaume , Dehmas Moukrane
Published: November 2017

Laue microdiffraction is used to determine the full elastic strain tensor of the γ and γ′ phases in grains of a nickel-based superalloy with a coarse-grained microstructure. A `rainbow' filter and an energy dispersive point detector are employed to measure the energy of Bragg reflections. For the two techniques, an uncertainty of ±2.5 × 10−3 Å is obtained for the undetermined crystal lattice parameter. Our measurements show that the filter method provides better confidence, energy resolution, accuracy and acquisition time. The sensitivity of each method with respect to the γ–γ′ lattice mismatch is demonstrated with measurements in samples with average precipitate sizes of 200 and 2000 nm. For the 200 nm precipitate size, the lattice mismatch is less than 2 × 10−3 Å and the dilatational strains are close to ±1.5 × 10−3 depending on the considered phase. For the 2000 nm precipitate size, the lattice mismatch is close to 8 × 10−3 Å and almost no elastic strain occurs in the microstructure.
A method to perform modulated structure studies using the program ZMC
Authors: Chan E. J. , Goossens D. J.
Published: November 2017

The Monte Carlo simulation toolkit ZMC provides a general method for Monte Carlo simulation of disordered molecular displacements, orientations and site occupations. It is part of a suite of programs that allows convenient calculation of three-dimensional reciprocal space diffraction intensities. Such intensities are useful for extensive structure interpretations from diffraction experiments. Some physical properties can also be calculated from the simulation. This article reports the implementation of an integrated ZMC module that facilitates the construction of modulated molecular crystals and allows the corresponding calculation of modulation satellites. Use of the module is explained and examples illustrated. The method is ideally suited for novice treatment of modulated structure features and also as a basic platform to explore complex structure/properties relationships using atomistic simulation techniques.
A quantile regression analysis of farmer cooperative performance
Authors: Grashuis Jasper
Published: November 2017

Purpose

A financial perspective of farmer cooperative performance is assumed by conceptualizing the cooperative as an independent firm. The purpose of this paper is to explore variability in the financial performance of the largest 1,000 US farmer cooperatives with emphasis on efficiency, productivity, and leverage.

Design/methodology/approach

Cooperative performance is analyzed by means of the extended DuPont identity, an accounting tool which decomposes return on equity into five ratios of efficiency, productivity, and leverage. The extended DuPont identity is applied empirically with quantile regression, which allows estimation of the statistical interrelationship of the DuPont components across the full response distribution.

Findings

Per the results, variability in the financial performance of US farmer cooperatives is for the most part associated with the operating profit margin, which confirms prior findings of cost inefficiency in the empirical literature. Therefore, US farmer cooperatives may improve financial performance by emphasizing sales and operating costs. Specifically, recommendations include placing emphasis on bargaining power, product differentiation, and scale economies. Supply cooperatives may also consider issuing non-qualified equity and securing long-term debt access as additional possibilities to improve financial performance.

Originality/value

The empirical application of the extended DuPont identity with quantile regression facilitates a novel investigation of cooperative performance by placing emphasis on the efficiency, productivity, and leverage of cooperatives with various degrees of performance.
Effect of input credit on smallholder farmers’ output and income
Authors: Iddrisu Adam , Ansah Isaac Gershon Kodwo , Nkegbe Paul Kwame
Published: November 2017

Purpose

The purpose of this paper is to examine the effect of input credit on smallholder farmers’ output and income using Masara N’Arziki support project in Northern Ghana.

Design/methodology/approach

A cross-sectional primary data set was used to estimate the effect of project participation on farm output, yield and income using propensity score matching (PSM) methods.

Findings

The findings are that project participation is skewed towards experienced farmers with big-sized households and farms. The effect of project on outcomes is somewhat unsatisfactory in the sense that participation only raises output and yield, but not income.

Research limitations/implications

The paper only examined the project effect on farm outcomes among smallholder farmers participating in the programme in just one operational area in the Northern region. Future research should consider all the operational areas for an informed generalisation of findings.

Practical implications

Greater benefits to farmers from programme participation would require project management to review the contractual arrangement so that the high cost of input credit is significantly reduced.

Originality/value

The paper applied the PSM to estimate the effect of project participation on farm output, yield and income among smallholder farmers which is non-existent in the literature on the study area, at least as far as we know. This paper can inform future policy on the direction and nature of support for smallholder farmers in Northern Ghana.
Exploring open innovation collaboration between SMEs and larger customers
Authors: Tobiassen Anita Ellen , Pettersen Inger Beate
Published: November 2017

Purpose

The purpose of this paper is to explore open innovation (OI) collaborations between high-tech small and medium-sized enterprises (SMEs) and large customers. The research aims to add new insights into how smaller firms attract and build trusting relationships with larger customers for the purpose of innovation, and to highlight customers’ contribution in SMEs’ innovation process.

Design/methodology/approach

This exploratory research is based on three case studies and adopts a process perspective to gather qualitative data on OI collaborations, focusing on the inherent dynamics, and evolution in long-term relationships.

Findings

The study provides insights into how SMEs develop OI relationships with both industry and research customers by building trust through various mechanisms. Motivated by the potential benefits of OI in strengthening the firms’ technological edge, the SME managers proactively and strategically developed and managed their OI relationships. The results proved that large customers contributed greatly to the SMEs’ innovation processes both directly and indirectly.

Practical implications

The research provides advice for smaller firms which are considering adopting an OI strategy with customers through mechanisms such as trust building and enhancing legitimacy.

Originality/value

The research adds to the OI literature on SMEs by exploring how smaller firms manage OI challenges, exploit benefits, and develop trusting relationships with larger customers and research institutions.
Web atmospherics as drivers of shopping centres’ customer loyalty
Authors: Savelli Elisabetta , Cioppi Marco , Tombari Federica
Published: November 2017

Purpose

The purpose of this paper is to analyse whether and how the website atmosphere (WA) of a shopping centre affects the behavioural loyalty of customers towards physical shopping centres. A mediating variable – individual shopper motivation – is considered in assessing this relationship.

Design/methodology/approach

The research hypotheses were tested using a partial least squares – path modelling approach to structural equation modelling on a sample population of 438 individuals.

Findings

Online atmospherics, particularly concerning the social/relational attributes of the WA, positively affect the behavioural loyalty of customers towards physical shopping centres. Moreover, recreational motivations strengthen this relationship more than functional motivations do.

Research limitations/implications

The sample investigated is limited with regard to diversity, age and gender. Future research can use a more representative sample to improve the findings’ relevance and generalisation. Also the development of a scale of measures for the shopping centre customers’ motivations is worthy of interest in future studies.

Practical implications

Recognising the importance of web atmospherics’ significant impact on customer loyalty should encourage shopping centre managers to develop effective website and online communication programmes.

Originality/value

Extant studies have paid little attention to the relationship between WA and customer loyalty to the physical shopping centre. This study investigates this relationship, combining the online and offline perspective into an overall research approach. Moreover, it contributes to the research on website management in the shopping centre context by providing a comprehensive analysis of WA, whereas previous studies have mainly focussed on one or a few atmospherics.
Developing and implementing a treatment intervention for college students found responsible for sexual misconduct
Authors: Lamade Raina V. , Lopez Elise , Koss Mary P. , Prentky Robert , Brereton Alexandra
Published: November 2017

Purpose

The purpose of this paper is to summarize the development of a treatment program for students found responsible of sexual misconduct.

Design/methodology/approach

This project, supported by the SMART (Office of Sex Offender Sentencing, Monitoring, Apprehending, Registering and Tracking) of the Department of Justice, was requested by The White House toward the end of President Obama’s last term and was intended to identify the confluence of factors related to sexual misconduct on college campuses, and to design a treatment program to address those factors.

Findings

This paper will discuss the unique factors of this population that ought to be considered to successfully develop an effective program, and the complexities of implementing treatment programs to this population, within a higher education system. This will include a discussion of barriers to implementation and challenges of employing treatment. This paper will present steps for implementing a treatment program and outline the core components of a treatment intervention for this population.

Originality/value

Implementing a treatment option for students found responsible of sexual misconduct that specifically targets the associated risk factors as part of a comprehensive approach to help improve campus safety.
Choosing a book by its cover: analysis of a reader’s choice
Authors: Gudinavičius Arūnas , Šuminas Andrius
Published: November 2017

Purpose

The massive growth in the number of book titles has made publishers think about how to attract a customer’s attention to particular books. This is the reason why the book cover plays an important role as a tool of communication with the reader. The research question of this exploratory study is whether the preference given by readers to book cover colors is different across genders and age groups when they choose the book in an online bookstore by its cover. The paper aims to discuss these issues.

Design/methodology/approach

The experiment in a bookstore and a library was done. Each respondent was asked to choose one book from our sample of 18 books and a mobile eye tracking laboratory was set up in order to find out the respondents’ basic gazing data. After conducting an experiment with bookstore and library visitors, the results showed that younger women tend to select a book by its cover (when the time for selection is not limited) statistically significantly faster than men of the same age group. The difference disappears with age.

Findings

The data of the experiment suggested that women from the age group 18-35 prefer books with cool color covers and the preference disappears with age; accordingly, men in the age group 56+ prefer books with warm color covers. The preference was not seen in younger age groups. The analysis of data on the number of choices for each cover and the time spent looking at each of them revealed a significant positive correlation between the women’s preferences in selecting covers and the time women spend looking at them; however, there was no such correlation in the case of men’s data.

Originality/value

The study has shown that the reader’s book choice is at least partly influenced by the cover color. The preference given to cool and warm colors and the speed of decision making show certain differences across genders and age groups. The result contributes to knowing how to create book covers more adopted to reader’s needs.
Building tourism-resilient communities by incorporating residents’ perceptions? A photo-elicitation study of tourism development in Bruges
Authors: Janusz Katarzyna , Six Sofie , Vanneste Dominique
Published: November 2017

Purpose

In a current trend of a growing amount of short city trips, it becomes crucial to understand how local residents perceive the presence of tourists and tourism in their cities and how their socio-cultural context influences those perceptions. The purpose of this paper is to contribute to this understanding which will enable the city planners to take actions to create the well-balanced and resilient communities in which the needs of residents and tourists are equally met.

Design/methodology/approach

To understand residents’ perceptions’ about tourism in Bruges, this research applied photo-elicitation interviews with 28 residents who lived in various locations in the historical center to understand socio-cultural background of residents, their tourism-related concerns and whether they are in line with what is commonly perceived as problematic in Bruges.

Findings

Results show that as long as residents can benefit from tourism and tourism-related infrastructure, they support tourism. On the other hand, tourism decreases the liveability of the historical center due to supersession of infrastructure serving the residents by tourist-oriented amenities.

Practical implications

To build a sustainable and resilient city in the future, the authorities of Bruges should cease further “museumification” of the historical city by breaking the hegemony of tourism industry, providing affordable housing and rethinking the concentration model of tourism.

Originality/value

The photo-elicitation method proved to produce rich content and good-quality data by stimulating respondents’ memories and evoking experiences and emotions. Thus, this paper recommends that future research about residents’ attitudes is developed around visual methods as they give voice to the residents and are able to uncover issues which are difficult to capture with other methods.
The Finnish healthcare services lean management
Authors: Hihnala Susanna , Kettunen Lilja , Suhonen Marjo , Tiirinki Hanna
Published: November 2017

Purpose

The purpose of this paper is to discuss health services managers’ experiences of management in a special health-care unit and development efforts from the point of view of the Lean method. Additionally, the aim is to deepen the knowledge of the managers’ work and nature of the Lean method development processes in the workplace. The research focuses on those aspects and results of Lean method that are currently being used in health-care environments.

Design/methodology/approach

These data were collected through a number of thematic interviews. The participants were nurse managers (n= 7) and medical managers (n= 7) who applied Lean management in their work at the University Hospital in the Northern Ostrobothnia Health Care District. The data were analysed with a qualitative content analysis.

Findings

A common set of values in specialized health-care services, development of activities and challenges for management in the use of the Lean manager development model to improve personal management skills.

Practical implications

Managers in specialized health-care services can develop and systematically manage with the help of the Lean method. This emphasizes assumptions, from the point of view of management, about systems development when the organization uses the Lean method. The research outcomes originate from specialized health-care settings in Finland in which the Lean method and its associated management principles have been implemented and applied to the delivery of health care.

Originality/value

The study shows that the research results and in-depth knowledge on Lean method principles can be applied to health-care management and development processes. The research also describes health services managers’ experiences of using the Lean method. In the future, these results can be used to improve Lean management skills, identify personal professional competencies and develop skills required in development processes. Also, the research findings can be used in the training of health services managers in the health-care industry worldwide and to help them survive the pressure to change repeatedly.
Subordinates’ core self-evaluations and performance predict leader-rated LMX
Authors: Henson Jeremy A. , Beehr Terry
Published: November 2017

Purpose

The purpose of this paper is to test the effects of subordinates’ individual differences or traits and their performance behavior on the formation of leaders’ LMX, based on leader-member exchange (LMX) theory, thus proposing that both who subordinates are and what they do may affect supervisors’ LMX perceptions.

Design/methodology/approach

Two studies were conducted. The first was a non-experimental field study and the second was a laboratory experiment.

Findings

Study 1, a non-experimental field study, HLM, showed that subordinates’ self-reported characteristics predict their leaders’ LMX ratings; Study 2, a laboratory experiment, showed that subordinate performance causes leaders’ LMX perceptions while holding subordinate’s individual differences constant.

Originality/value

The current research was the first to demonstrate experimentally that LMX develops over multiple interactions. Additionally, it demonstrates that task-oriented behavior (i.e. job performance) and personality characteristics (i.e. internal locus of control and self-efficacy) are predictors of LMX.