bluuebunny/crossref_metadata_2025 huggingface dataset:
Diversity of two-component systems: insights into the signal transduction mechanism by the Staphylococcus aureus two-component system GraSR
Authors: Muzamal Uzma , Gomez Daniel , Kapadia Fenika , Golemi-Kotra Dasantila
Published: October 2014

The response to cationic antimicrobial peptides (CAMPs) in Staphylococcus aureus relies on a two-component system (TCS), GraSR, an auxiliary protein GraX and an ATP-binding cassette (ABC) transporter, VraF/G. To understand the signal transduction mechanism by GraSR, we investigated the kinase activity of the cytoplasmic domain of histidine kinase GraS and the interaction with its cognate response regulator GraR. We also investigated interactions among the auxiliary protein GraX, GraS/R and the ATPase protein of the ABC transporter, VraF. We found that GraS lacks autophosphorylation activity, unlike a similar histidine kinase, BceS, of Bacillus subtilis. In addition, the interaction between GraS and GraR is very weak in comparison to the stronger interaction observed between BceS and its conjugated response regulator, BceR, suggesting that CAMP signaling may not flow directly from GraS to GraR. We found that the auxiliary protein GraX interacts with VraF and GraR, and requires the histidine phosphotransfer and dimerization domain of GraS to interact with this protein. Further, VraF requires the GraS region that connects the membrane-bound domain with the cytoplasmic domain of this protein for interaction with GraS. The interactions of GraX with GraS/R and VraF indicate that GraX may serve as a scaffold to bring these proteins in close proximity to GraS, plausibly to facilitate activation of GraS to ultimately transduce the signal to GraR.
Addition of transversus abdominis plane block to patient controlled analgesia for laparoscopic high anterior resection improves analgesia, reduces opioid requirement and expedites recovery of bowel function
Authors: Ris F , Findlay JM , Hompes R , Rashid A , Warwick J , Cunningham C , Jones O , Crabtree N , Lindsey I
Published: October 2014

Introduction

Opioid sparing in postoperative pain management appears key in colorectal enhanced recovery. Transversus abdominis plane (TAP) blocks offer such an effect. This study aimed to quantify this effect on pain, opioid use and recovery of bowel function after laparoscopic high anterior resection.

Methods

This was a retrospective analysis of prospective data on 68 patients. Patients received an epidural (n=24), intravenous morphine patient controlled analgesia (PCA, n=22) or TAP blocks plus PCA (n=22) determined by anaesthetist preference. Outcome measures were numerical pain scores (0–3), cumulative intravenous morphine dose and time to recovery of bowel function (passage of flatus or stool).

Results

There were no differences in patient characteristics, complications or extraction site. The TAP block group had lower pain scores (0.7 vs 1.36, p<0.001) and morphine requirements (8mg vs 15mg, p=0.01) than the group receiving PCA alone at 12 hours and 24 hours. Earlier passage of flatus (2.0 vs 2.7 vs 3.4 days, p=0.002), stool (3.1 vs 4.1 vs 5.5 days, p=0.04) and earlier discharge (4 vs 5 vs 6 days, p=0.02) were also seen.

Conclusions

Use of TAP blocks was found to reduce pain and morphine use compared with PCA, expedite recovery of bowel function compared with PCA and epidural, and expedite hospital discharge compared with epidural.
Abdominal aortic occlusion and vascular compromise secondary to acute gastric dilatation in a patient with bulimia
Authors: Elsharif M , Doulias T , Aljundi W , Balchandra S
Published: October 2014

Acute gastric dilation is a rare but recognised complication in patients with bulimia and anorexia following binge episodes owing to decreased bowel motility. We present a rare case of acute gastric dilation secondary to bulimia in an otherwise healthy 18-year-old female patient that resulted in compression and complete occlusion of the abdominal aorta, leading to acute mesenteric and bilateral lower limb ischaemia. This resolved immediately following a laparotomy and gastric decompression.

Management of these patients is very challenging owing to the lack of a successful precedent. To our knowledge, such a catastrophic complication has only ever been reported once in the literature and the outcome was fatal. Our case is of additional importance as it offers a successful management strategy for these patients.
The use of shoulder scoring systems and outcome measures in the UK
Authors: Varghese M , Lamb J , Rambani R , Venkateswaran B
Published: October 2014

Introduction

In future, outcomes following shoulder surgery may be subject to public survey. Many outcome measures exist but we do not know whether there is a consensus between shoulder surgeons in the UK. The aim of this study was to survey the preferred outcome measures used by National Health Service (NHS) shoulder surgeons operating in the UK.

Methods

A total of 350 shoulder surgeons working in NHS hospitals were asked to complete a short written questionnaire regarding their use of scoring systems and outcome measures. Questionnaires were sent and responses were received by post.

Results

Overall, 217 responses were received (62%). Of the respondents, 171 (79%) use an outcome measure in their shoulder practice while 46 (21%) do not. There were 118 surgeons (69%) who use more than one outcome measure. The Oxford shoulder score was most commonly used by 150 surgeons (69%), followed by the Constant score with 106 (49%), the Oxford shoulder instability score with 82 (38%), and the Disabilities of the Arm, Shoulder and Hand score with 54 (25%). The less commonly used outcome measures were the SF-36® and SF-12® health questionnaires with 19 (9%), the University of California at Los Angeles activity score with 8 (4%), the American Shoulder and Elbow Surgeons shoulder assessment form with 8 (4%) and the EQ-5D™ with 10 (3%).

Conclusions

Validated outcome measures should be adopted by all practising surgeons in all specialties. This will allow better assessment of treatments in addition to assessment of surgical performance in a transparent way.
The role of laparoscopic surgery in the management of a malfunctioning peritoneal catheter
Authors: Alabi A , Dholakia S , Ablorsu E
Published: October 2014

Introduction

Peritoneal catheter malfunction is a common complication of peritoneal dialysis (PD). It has a high failure rate with conservative management. Catheter replacement was historically the standard surgical treatment of choice. Nowadays, laparoscopy has been introduced as an alternative surgical modality to rescue the malfunctioning peritoneal catheter and also offers the possibility of replacement if indicated. The aim of this study was to compare the outcomes of these two surgical modalities.

Methods

The medical records of consecutive patients who underwent surgical treatment for malfunctioning PD catheters (between January 2010 and April 2013) were analysed. The primary outcome included successful return to adequate PD. The secondary endpoint was length of catheter patency and the cause of catheter failure.

Results

A total of 32 cases were identified, of which 8 had open catheter replacement and 24 had a laparoscopic intervention. The overall median follow-up duration was 12.5 months. The success rate for laparoscopic surgery in terms of functioning catheter at 12 months was 62.5% but only 37.5% for open surgery. The mean length of catheter patency after laparoscopic intervention was 31.6 months compared with only 13.6 months for the open surgery group. The most common cause of catheter failure diagnosed during laparoscopic intervention was catheter migration (33.0%), followed by omental wrap and catheter blockage by fibrin/blood plug (25.0% each). Open surgery did not have any diagnostic potential.

Conclusions

Laparoscopy is the treatment of choice for malfunctioning PD. Its proven benefit includes simultaneous identification of the aetiological cause of malfunction together with direct correction of this problem, thereby maximising outcome. It also allows for rapid recommencement of PD and avoidance of haemodialysis, saving cost and resources.
Video assisted thoracoscopic thyroidectomy for retrosternal goitre
Authors: Gupta P , Lau KKW , Rizvi I , Rathinam S , Waller DA
Published: October 2014

Introduction

Thyroidectomy for retrosternal goitre is usually carried out through a cervical incision. Around 4–12% of patients, however, require an extracervical approach, usually by sternotomy. Anatomically, the thyroid extends deep behind the great vessels in the pretracheal fascia. A sternotomy is therefore not only a substantial incision but this anterior approach is also not ideal for exposure. We report the use of video assisted thoracoscopic surgery (VATS) instead of a sternotomy or thoracotomy in conjunction with a transverse cervical incision for these patients.

Methods

A retrospective descriptive study was carried out of seven patients with retrosternal goitre who underwent a VATS thyroidectomy.

Results

Twenty-one patients with retrosternal goitre were referred to our institution for surgical excision with the anticipation of requiring an extracervical incision. Of these, seven (median age: 68 years, range: 58–73 years) underwent a VATS thyroidectomy. The median operating time was 218 minutes (range: 120–240 minutes). The median diameter of the retrosternal goitre was 70mm (range: 40–145mm). Only one patient required conversion to a manubriotomy to deliver the bulky thyroid and one patient suffered a transient right recurrent laryngeal nerve palsy. The median postoperative pain scores for days 0 and 1 were 1 (range: 0–5) and 0 (range: 0–3) respectively. The median length of stay was 5 days (range: 3–7 days).

Conclusions

The use of VATS in thyroidectomy for retrosternal goitre offers a minimally invasive approach resulting in less morbidity while affording excellent exposure.
Implications of the shape of training review for surgery
Authors: Ferguson HJM , Fitzgerald JEF , Beamish AJ
Published: October 2014

Published in 2013, the Shape of Training review is an independent review of postgraduate medical training overseen by Professor david Greenaway. 1 This review has set out recommendations for the structure and delivery of training for the next 30 years, 1 including a framework and timescale for this reconfiguration. There is a wide range of key themes, listed in Table 1 . The changes proposed in its 19 recommendations are far-reaching, with implications for both current and future surgical trainees in the UK.
The chavasse report
Authors: Briggs Tim
Published: October 2014

So far in 2014 we have commemorated the 70th anniversary of the D-Day landings and the 100th anniversary of the outbreak of the First World War. In september we watched the Invictus games, which showed the amazing fortitude and functional recovery of our wounded service personnel.
Simulation in orthopaedic training: would a national curriculum improve trainees’ surgical skills?
Authors: Templeton-Ward Oliver , Solan Matthew
Published: October 2014

Orthopaedic surgical education is undergoing a transition, requiring trainees to learn a greater number of complex surgical skills but with a reduction in learning opportunities. simulation has been proposed as one way to help solve this dichotomy. The Joint Committee on Surgical Training (JCST) hopes to incorporate simulation into the curriculum for all specialties. Our findings indicate that there is as yet no clear consensus in the literature that simulation in orthopaedic surgery provides a reliable and valid way of improving surgical skills. We therefore urge the JCST to commission a pilot study using its recently published simulation curriculum before making the large investment that would be required to roll it out nationwide.
Can Oral Nutritional Supplements Improve Medicare Patient Outcomes in the Hospital?
Authors: Lakdawalla Darius N. , Snider Julia Thornton , Perlroth Daniella J. , LaVallee Chris , Linthicum Mark T. , Philipson Tomas J. , Partridge Jamie S. , Wischmeyer Paul E.
Published: October 2014

We analyzed the effect of oral nutritional supplement (ONS) use on 30-day readmission rates, length of stay (LOS), and episode costs in hospitalized Medicare patients (≥65), and subsets of patients diagnosed with acute myocardial infarction (AMI), congestive heart failure (CHF) or pneumonia (PNA). Propensity-score matching and instrumental variables were used to analyze ONS and non-ONS episodes from the Premier Research Database (2000–2010). ONS use was associated with reductions in probability of 30-day readmission by 12.0% in AMI and 10.1% in CHF. LOS decreases of 10.9% in AMI, 14.2% in CHF, and 8.5% in PNA were associated with ONS, as were decreases in episode costs in AMI, CHF and PNA of 5.1%, 7.8% and 10.6%, respectively. The effect on LOS and episode cost was greatest for the Any Diagnosis population, with decreases of 16.0% and 15.8%, respectively. ONS use in hospitalized Medicare patients ≥65 is associated with improved outcomes and decreased healthcare costs, and is therefore relevant to providers seeking an inexpensive, evidence-based approach for meeting Affordable Care Act quality targets.
Optimization Approach to Design Single Feed Symmetric and Asymmetric Multibeam Reflectarrays
Authors: Gómez Josefa , Tayebi Abdelhamid , Cátedra Felipe
Published: October 2014

A novel optimization method to design the layout of printed reflectarrays for multibeam operation is presented in this paper. The proposed approach allows using different classes of cell elements to design the layout of reflectarrays. Therefore, phase curves do not have to fulfill the requirement of having a phase range wider than 360°. The dimensions of each cell element are adjusted to achieve the required phase distribution to radiate symmetric or asymmetric multiple beams. Five different reflectarrays have been designed by using this technique. Numerical simulations demonstrate high gain performance and low side lobe levels.
Precise Ionosphere Monitoring via a DSFH Satellite TT&C Link
Authors: Chen Xiao , Li Guangxia , Li Zhiqiang , Yue Chao
Published: October 2014

A phase-coherent and frequency-hopped PN ranging system was developed, originally for the purpose of anti-jamming TT&C (tracking, telemetry and telecommand) of military satellites of China, including the Beidou-2 navigation satellites. The key innovation in the synchronization of this system is the unambiguous phase recovery of direct sequence and frequency hopping (DSFH) spread spectrum signal and the correction of frequency-dependent phase rotation caused by ionosphere. With synchronization achieved, a TEC monitoring algorithm based on maximum likelihood (ML) principle is proposed and its measuring precision is analyzed through ground simulation, onboard confirmation tests will be performed when transionosphere DSFH links are established in 2014. The measuring precision of TEC exceeds that obtained from GPS receiver data because the measurement is derived from unambiguous carrier phase estimates, not pseudorange estimates. The observation results from TT&C stations can provide real time regional ionosphere TEC estimation.
Outage Probability of SINR for Underlay Cognitive Radio Systems in Nakagami Fading
Authors: Jarrouj Jiana , Blagojevic Vesna , Ivanis Predrag
Published: October 2014

In this paper underlay cognitive radio system is analyzed in Nakagami fading environment, for the case when the available channel state information (CSI) of the link from the secondary transmitter to the primary receiver is outdated. We considered the case when both interference and transmit power constraints are applied. The impact of the co-channel interference that originates from the primary user is analyzed in details. The exact closed-form expressions for probability density function, outage probability, and the moments of signal-to-interference and noise ratio (SINR) at the secondary user's receiver are derived. The analytical expressions are verified by using independent Monte Carlo simulation method.
New Design of Integrated 2D Photonic Crystal Narrow Band Filters Using the FDTD-2D Method
Authors: Badaoui Hadjira Abri , Abri Mehadji
Published: October 2014

In this paper, integrated 2D photonic crystal narrow band filter design is achieved based on transmission spectra shift. The presented effective technique for the design of narrow band resonant filters obtained by one-missing-row and by choosing proper radii of air holes of the waveguide is proposed. The 2D photonic crystals are designed by utilizing cascaded waveguides with different radii of air holes. The results are presented for normal incident wave with TE polarizations with a narrow spectral bandwidth centered at λ = 1.55 μm. We also discuss the filtering process and its necessary modifications to achieve efficient filtering. A final synthesized filter topology is presented and a band from 1.53 μm to 1.57 μm around 1.55 μm is transmitted with a maximum transmission of about 77% with better performances is achieved.
A Proposed Stealthy Target Detection in Ground Plane Effect Based on Balloon-borne Netted System Using Hybrid (PO/TDOA) Method
Authors: Barbary Mohamed , Zong Peng
Published: October 2014

A proposed detection technique for stealthy target model F-117A based on balloon-borne netted radar system is applied. One of the potential problems of the proposed scheme is the ground plane effect caused by the high altitude platform. In this paper, we present a proposed study of the ground plane effect on the stealthy detection based on a new hybrid of the physical optics (PO) and time difference of arrival (TDOA) methods. Through simulation, the effect results of all parameters characterizing the clutter on balloon fall point distribution are obtained. To achieve high location accuracy of stealthy model, we proposed a scheme of detecting stealthy model in ground plane effect by using accurate radar cross section (RCS) measurement to compute the stealthy target position based on PO formulation. The netted radar sensitivity of proposed scheme has been improved due to increasing PO-scattered field of stealthy model with higher aspect angles of balloon-borne comparing to the conventional ground-based netted system, which has limited observability and poor detection due to low signal-to-noise ratio (SNR). Simulations demonstrate that proposed scheme gives much higher location accuracy and reduces location errors comparing to the conventional system.
Evaluation of Efficiency of Transcoding Steganography
Authors: Janicki Artur , Mazurczyk Wojciech , Szczypiorski Krzysztof
Published: October 2014

Nowadays cyber criminalists’ interest in incorporation of steganography into armory of rogue hackers is on the rise and information hiding techniques are becoming the new black among Black Hats. In this paper we focus on analyzing the efficiency of the recently proposed IP telephony information hiding method called transcoding steganography (TranSteg) that enables hidden communication with a high steganographic bandwidth while retaining good voice quality. Specifically, we focus on analyzing which voice codecs would be the most favourable for TranSteg to minimize the negative influence on voice quality while maximizing the obtained steganographic bandwidth and limiting the risk of detection.
From Weakest Link to Security Hero: Transforming Staff Security Behavior
Authors: Pfleeger Shari Lawrence , Sasse M. Angela , Furnham Adrian
Published: October 2014

Practitioners, researchers and policy-makers involved with cyber security often talk about “security hygiene:” ways to encourage users of computer technology to use safe and secure behavior online. But how do we persuade workers to follow simple, fundamental processes to protect themselves and others? These issues are raised by behavioral scientists, to encourage worker, passenger and patient compliance. In this paper, we explore and summarize findings in social psychology about moral values and habit formation, and then integrate them into suggestions for transforming staff security behavior online.
A longitudinal study of brainstem auditory response from birth to late term in late preterm babies and abnormal findings in high-risk babies
Authors: Jiang Ze Dong
Published: October 2014

Objectives: The objective of this study was to examine brainstem auditory function in late preterm babies from birth to late term and detect abnormality in high-risk babies.

Methods: A total of 125 babies born at 33–36 weeks’ gestations were studied by longitudinally recording brainstem auditory evoked response from birth to postconceptional age (PCA) 42 weeks. The data were compared between 88 babies who had various perinatal problems (high-risk group) and 37 babies who had no major perinatal problems (healthy group).

Results: As PCA increased from 33 to 42 weeks, all wave latencies and I-V interpeak interval in brainstem auditory evoked response were decreased, while all wave amplitudes were increased in these babies. At PCA 33–34 weeks, wave III and V latencies and I-V interval in the high-risk late preterm babies were significantly longer than those in the healthy late preterm babies (P<0.05–0.01). At PCA 35–36 weeks, both V latency and I-V interval were significantly longer than those in the healthy babies (P<0.05 and 0.01). During the term period (PCA 37–42 weeks), these differences became smaller with increasing age. The wave V latency and I-V interval in the high-risk babies were significantly longer than those in the healthy babies at PCA 37–38 and 39–40 weeks (all P<0.05), though not significantly at PCA 41–42 weeks. The amplitudes of waves I, III, and V all tended to be smaller than those in the healthy babies.

Conclusions: During early life, brainstem auditory function is abnormal in high-risk late preterm babies. The abnormality is most significant at early preterm, improves with increasing age and approaches normal at late term.
Complementizer agreement in eastern Wisconsin: (Central) Franconian features in an American heritage language community
Authors: Bousquette Joshua
Published: October 2014

The present study shows that Wisconsin Heritage German licenses complementizer agreement for second person singular, with inflectional affixes developed through the reanalysis of phonetically-derived hiatus effects. Most frequently attested in speakers with direct ancestry to Franconian-speaking regions, this phenomenon is restricted to second person singular, consistent with the input varieties at time of immigration. Analyzed diachronically, complementizer agreement is shown to progress through a linguistic cycle involving the reanalysis and subsequent compensatory reinforcement of subject pronouns, with Wisconsin Heritage German exhibiting the earliest stage of this cycle.
Complex complementizers and the structural relation with weak T. New (morpho)syntactic data from a Pomeranian language island in Brazil
Authors: Postma Gertjan
Published: October 2014

In this paper I discuss three properties of Brazilian Pomeranian, a Germanic language spoken in Espirito Santo, Brazil by descendents who emigrated in the 19th century. These three aspects of the verbal system are: 1. The relation between complex complementizers, a two-infinitive system, and split infinitives, previously discussed in van Gelderen (1993, 1998) and Schallert (2012, 2013), 2. Verb Projection Raising (VPR), as discussed by Riemsdijk 2002, Haegeman 2007, Salzmann 2011, and Brandner & Salzmann 2012, and 3. Verb-Second positioning of verbal clusters, previously discussed in Vos (2005). I discuss novel Pomeranian data from the perspective of the literature on these three topics, which have been thus far studied largely separately from one another. An integrated discussion sheds light on the nature and the proper analysis of these three phenomena. I argue that these phenomena are caused by the “weaknesses” of T. The weakness of T can be resolved “downward” by copying features onto T under selection by a higher head (agree), or can be resolved “upward” under head movement of T.
Helping Graduate Teaching Assistants in Biology Use Student Evaluations as Professional Development
Authors: Kendall K. Denise , Niemiller Matthew L. , Dittrich-Reed Dylan , Schussler Elisabeth E.
Published: October 2014

Graduate teaching assistants (GTAs) are often used as instructors in undergraduate introductory science courses, particularly in laboratory and discussion sections associated with large lectures. These GTAs are often novice teachers with little opportunity to develop their teaching skills through formal professional development. Focused self-reflection about end-of-semester teaching evaluations may be an important informal supplement to teacher training. To inform this practice, we explored the instructional behaviors that undergraduates perceived as most important for GTAs’ teaching effectiveness in laboratory courses. In spring semester 2012, 1159 undergraduates in freshman-level biology lab courses rated their GTAs on 21 instructional behaviors, the GTAs’ teaching effectiveness, the amount the student learned, and their expected grade in the laboratory. Using linear mixed models, we found that instructional behaviors related to the categories of teaching techniques and interpersonal rapport best predicted student ratings of GTAs’ teaching effectiveness. GTAs or other novice teachers can use this information to identify specific areas for instructional improvement when considering student feedback about their teaching.
Using a Combined Approach of Guided Inquiry & Direct Instruction to Explore How Physiology Affects Behavior
Authors: Machtinger Erika T.
Published: October 2014

Hands-on activities with live organisms allow students to actively explore scientific investigation. Here, I present activities that combine guided inquiry with direct instruction and relate how nutrition affects the physiology and behavior of the common housefly. These experiments encourage student involvement in the formulation of experimental design, promoting engagement in the learning process. These activities are suitable for both postsecondary education and high school classroom settings and highlight National Science Education Standards, particularly by promoting inquiry-based learning and communicating science explanations.
Work Ability Index (WAI) and Its Health‐related Determinants among Iranian Farmers Working in Small Farm Enterprises
Authors: Rostamabadi Akbar , Mazloumi Adel , Foroushani Abbas Rahimi
Published: October 2014

Work Ability Index (WAI) and Its Health‐related Determinants among Iranian Farmers Working in Small Farm Enterprises: Akbar ROSTAMABADI, et al. Department of Occupational Health Engineering, Ashtian Health Care Center, Arak University of Medical Sciences, Iran—

Objectives

This study aimed to determine the Work Ability Index (WAI) and examine the influence of health dimensions and demographic variables on the work ability of Iranian farmers working in small farm enterprises.

Method

A cross‐sectional study was conducted among 294 male farmers. The WAI and SF‐36 questionnaires were used to determine work ability and health status. The effect of demographics variables on the work ability index was investigated with the independent samples t‐test and one‐way ANOVA. Also, multiple linear regression analysis was used to test the association between the mean WAI score and the SF‐36 scales.

Results

The mean WAI score was 35.1 (SD=10.6). One‐way ANOVA revealed a significant relationship between the mean WAI and age. Multiple linear regression analysis showed that work ability was more influenced by physical scales of the health dimensions, such as physical function, role‐physical, and general health, whereas a lower association was found for mental scales such as mental health.

Conclusions

The average WAI was at a moderate work ability level for the sample population of farmers in this study. Based on the WAI guidelines, improvement of work ability and identification of factors affecting it should be considered a priority in interventional programs. Given the influence of health dimensions on WAI, any intervention program for preservation and promotion of work ability among the studied farmers should be based on balancing and optimizing the physical and psychosocial work environments, with a special focus on reducing physical work load.
Work Stressors, Perseverative Cognition and Objective Sleep Quality: A Longitudinal Study among Dutch Helicopter Emergency Medical Service (HEMS) Pilots
Authors: Radstaak Mirjam , Geurts Sabine A. E. , Beckers Debby G. J. , Brosschot Jos F. , Kompier Michiel A. J.
Published: October 2014

Work Stressors, Perseverative Cognition and Objective Sleep Quality: A Longitudinal Study among Dutch Helicopter Emergency Medical Service (HEMS) Pilots: Mirjam RADSTAAK, et al. Behavioural Science Institute, Radboud University Nijmegen, The Netherlands—

Objectives

This longitudinal study examined the associations between work stressors, perseverative cognition and subjective and objective sleep quality. We hypothesized work stressors to be associated with (i) poor nocturnal sleep quality and (ii) higher levels of perseverative cognition during a free evening. We further hypothesized (iii) perseverative cognition to be associated with poor nocturnal sleep quality and (iv) the association between work stressors and sleep quality to be mediated by perseverative cognition.

Methods

The participants were 24 pilots working for the Dutch Helicopter Emergency Medical Service (HEMS). They completed six questionnaires: at the end of three consecutive day shifts and each morning following the shifts. The questionnaires addressed work stressors (workload, distressing shifts and work‐related conflicts), subjective sleep quality and perseverative cognition. Participants wore actigraphs to assess sleep onset latency, total sleep time and number of awakenings.

Results

Correlation analysis revealed that (i) distressing shifts were related to delayed sleep onset (r=0.50, p=0.026) and that workload was related to impaired sleep quality (e.g., subjective sleep quality: r=−0.42, p=0.044). Moreover, (ii) distressing shifts were positively related to perseverative cognition (r=0.62, p=0.002), (iii) perseverative cognition delayed sleep onset (r=0.74, p<0.001) and (iv) mediated the association between distressing shifts and sleep onset latency.

Conclusions

Perseverative cognition may be an explanatory mechanism in the association between work stressors and poor sleep.
Effect of fruit size on the growth and development of Andean blueberry (Vaccinium meridionale Swartz) seedlings from four locations in the Colombian Andes
Authors: García M. Cristian Leonardo , Ligarreto M. Gustavo Adolfo
Published: October 2014

Andean blueberry propagation is done with wild plants and there is an absence of knowledge for the agronomical potential of the available materials for sexual propagation. Therefore, developing a propagation protocol that provides technical information for field growers is needed. The present paper aimed to evaluate the effect of the size of the fruits that were used to extract the seeds on the growth and development of Andean blueberry plants during the germination and nursery stages, comparing fruits from four different regions of Colombia: Antioquia, Cauca, Cundinamarca and Boyaca. During the germination stage, seeds from Antioquia and Cauca showed the best results with germination rates close to 90% and reached important physiological events, such as seed coat cracking and radicle extension earlier than seeds from Boyaca and Cundinamarca. In the nursery stage, fruit size significantly affected the growth variables, such as plant height and leaf length, in all the different seed origins. Seedlings from Boyaca showed better results for growth and development after transplanting, as indicated by a higher amount of leaves and presence of basal branching, followed by seedlings from Cauca, Cundinamarca and Antioquia, which showed delayed phenological events.
Effect of NaCl salinity on seed germination and seedling emergence of purple passion fruit (Passiflora edulis Sims)
Authors: Montaña Luis Ariel , Fischer Gerhard , Magnitskiy Stanislav , Zuluaga Guillermo
Published: October 2014

The purple passion fruit is propagated by seeds, but factors, such as hardiness and impermeability of the testa and salinity and pH of the soil, give rise to problems in germination and uniformity of seedlings. The objectives of the study were to evaluate the effect of different NaCl concentrations (0, 30, 60, 90, and 120 mM, corresponding to 0.8, 3.0, 6.0, 9.0, and 12.2 dS m-1) on the germination and emergence of purple passion fruit seeds. For the germination test, 50 seeds per Petri dish were used, which were watered with a saline solution weekly. A seed was considered germinated when the radicle reached 2 mm. In the case of seedling emergence, 50 seeds were sown in cleaned river sand at a 1 cm depth on polystyrene trays, covered with transparent plastic film. They were irrigated weekly with different NaCl concentrations and the electrical conductivity (EC) of the substrate was measured. A seedling was considered emerged when the hypocotyl was fully erect. The results showed significant differences, with germination being higher in seeds treated with 30 mM NaCl than in the control seeds, and no statistical differences for the 60 and 90 mM NaCl treatments. The emergence was significantly higher in the 0 (0.05 dS m-1 of the substrate) and 30 mM NaCl (0.71 dS m-1) treated seeds when compared with 60 mM (1.25 dS m-1), 90 mM (1.69 dS m-1) and 120 mM NaCl (2.30 dS m-1 of the substrate). There was a decline in the chlorophyll contents of the seedling cotyledons and an increased substrate EC with increasing NaCl concentrations.
Socio-economic perspectives of family farming in South America: cases of Bolivia, Colombia and Peru
Authors: Barrientos-Fuentes Juan Carlos , Torrico-Albino Juan Carlos
Published: October 2014

Family farming is very important because it is, among other types, the principal source of food and employment, especially in developing countries. Given the constant changes in the agrarian structure and environment, what are the prospects of family farming under current conditions in South America? To answer this question, we have chosen three countries from this continent: Bolivia, Colombia, and Peru. Based on a literature review of case studies in each country, a comparative analysis of the following topics was carried out: purpose of family farming, production unit, and agricultural production, integration with the market, income, and food security. Many similarities were found in the studied countries, which allow for some generalizations in certain aspects related to the studied cases. Family farming is largely moving to the rhythm of the markets. Its transition from a condition of subsistence to commercial status depends mainly on the availability of sufficient resources for production: mainly land, labor, and financial capital. The scarcity of these resources is forcing farming families to seek other sources of income or to migrate. The monetization of farming is increasing.
Growth analysis in chard plants (Beta vulgaris L. Cicla, cv. 'Pencas Blancas') exposed to different light quality
Authors: Casierra-Posada Fánor , Zapata-Casierra Esteban , Chaparro-Chaparro Daniel A.
Published: October 2014

To determine the effects of light quality on the growth indices of plants, Pencas Blancas cultivar chard plantlets were grown for 2 months under five different light treatments, obtained by filtering sunlight through colored polyethylene films. The treatments included: red, blue, green, yellow and transparent cover colors. A transparent cover (white light) was used as the control. The colored covers affected the plant growth. The plants grown under the yellow cover presented a better behavior with regards to growth, taken as: total dry weight per plant, leaf area, specific leaf area, absolute growth rate, relative growth rate, harvestable dry matter and root to shoot ratio. The dry matter partitioning in the leaves and roots was affected by the light quality, but not in the petioles, with a higher accumulation of dry mass in the leaves of plants grown under the yellow cover. As a consequence of the enhanced leaf area in the plants under the yellow cover, they also had the highest water uptake. On the other hand, the highest net assimilation rate value was found in plants grown under the transparent cover. These results open up the possibility of using yellow colored cover in leafy green vegetables, especially in chard plants grown under controlled conditions.
Pruning affects the vegetative balance of the wine grape (Vitis vinifera L.)
Authors: Serrano-Cely Pablo Antonio , Forero-Ulloa Fabio Emilio , Arango Johana , Puerto Ángela Milena
Published: October 2014

The cultivation of grapes for the production of wine at altitudes between 2,200 and 2,600 masl started in the department of Boyacá in 1982. Quality wines are produced by the Ain Karim Vineyard in Ricaurte High. It is necessary to have wine grapes that possess suitable organoleptic compounds at harvest in order to guarantee quality grape must that can be converted into wine. For this, it is necessary to have a suitable ratio between the inflows and the outflows and to guarantee production, quality and vegetative sustainability over time, conserving the equilibrium and benefiting the productive potential of the vineyard. This study aimed to evaluate the productive and vegetative balance effect in the wine grape varieties (Vitis vinífera L.) Cabernet Sauvignon and Sauvignon Blanc in Sutamarchán-Boyacá, considering different pruning types (short, long, and mixed). A bifactorial, completely random statistical design was used. At the time of harvest, the fruit production and pruned wood were evaluated. The long-pruned vines presented the best behavior and the most balanced inflow/outflow ratio, while Sauvignon Blanc demonstrated a better productive yield. Meanwhile, the short and mixed prunings presented the better values for the ravaz index, indicating that they are more suitable for the conditions of the region, allowing for sustainability during the productive cycles of the wine grapes.
Antioxidant capacity and total phenolic content of air-dried cape gooseberry (Physalis peruviana L.) at different ripeness stages
Authors: Narváez-Cuenca Carlos Eduardo , Mateus-Gómez Ángela , Restrepo-Sánchez Luz Patricia
Published: October 2014

Because the use of drying at high temperatures might negatively affect the functional properties of fruits, the effect of air-drying at 60°C on the total phenolic content (TPC) and antioxidant capacity (AOC) of cape gooseberry fruit was evaluated at three ripeness stages. The AOC was evaluated with 2,2'-azino-bis(3- ethylbenzothiazoline-6-sulfonic acid) (ABTS ), ferric reducing ability of plasma (FRAP), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and b-carotene-linoleate assays. The TPC and AOC increased in the fresh fruit as the ripeness stage increased. The TPC increased from 401.8±19.8 to 569.3±22.3 mg GA E/100 g dry weight (DW). The AOC values obtained with ABTS in the fresh fruit (ranging from 79.4±4.5 to 132.7±12.9 mmol trolox/g fruit DW) were comparable to those obtained with FRAP (ranging from 82.9±16.3 to 153.9±31.7 mmol trolox/g fruit DW). The values assessed with DPPH ranged from 21.0±3.2 to 34.1±5.1 mmol trolox/g fruit DW. The b-carotene-linoleate assay gave values ranging from 5.8±1.1 to 12.7±2.0 mmol a-tocoferol/g fruit DW. Air-drying the cape gooseberry fruit had a small influence on the TPC. The air-dried fruit had AOC values ranging from 27 to 164% of the value of the fresh fruit. While the ABTS assay produced higher values in the air-dried fruit than in the fresh fruit, the FRAP, DPPH, and b-carotene-linoleate assays resulted in lower values in the air-dried fruit.
Potential growing model for the standard carnation cv. Delphi
Authors: Lopez M. Miguel Ángel , Chaves C. Bernardo , Flórez R. Víctor Julio
Published: October 2014

The cut flower business requires exact synchronicity between product offer and demand in consumer countries. Having tools that help to improve this synchronicity through predictions or crop growth monitoring could provide an important advantage to program standards and corrective agronomic practices. At the Centro de Biotecnología Agropecuaria, SENA (SENA's Biotechnology, Agricultural and Livestock Center), located in Mosquera, Cundinamarca, a trial with standard carnation cv. Delphi grown under greenhouse conditions was carried out. The objective of this study was to build a simple model of dry matter (DM) production and partition of on-carnation flower stems. The model was based on the photosynthetically active radiation (PAR) MJ m-2 d-1 and temperature as exogenous variables and assumed no water or nutrient limitations or damage caused by pests, disease or weeds. In this model, the daily DM increase depended on the PAR, the light fraction intercepted by the foliage (FLINT) and the light use efficiency (LUE) g MJ-1. The LUE in the vegetative and reproductive stages reached values of 1.31 and 0.74 g MJ-1, respectively. The estimated extinction coefficient (k) value corresponded to 0.53 and the maximum FLINT was between 0.79 and 0.82. Partitioning between the plant vegetative and reproductive stages was modeled based on the hypothesis that the partition is regulated by the source sink relationship. The estimated partition coefficient for the vegetative stage of the leaves was 0.63 and 0.37 for the stems. During the reproductive stage, the partitioning coefficients of leaves, stems and flower buds were 0.05, 0.74, and 0.21, respectively.
Tunable and Wireless Photoimpedance Light Sensor
Authors: Saxena Tanuj , Rumyantsev Sergey , Dutta Partha , Shur Michael
Published: October 2014

We report on the effects of the frequency dispersion in light sensitive materials used in photoimpedance wireless sensors. An example of such a sensor is a gated semiconductor connecting two or more fixed capacitances. The impedance of the device under illumination is changed by the change in the photoresistance of the semiconductor layer and the change in the gate-semiconductor capacitance. We report on the design and simulation of the frequency dispersion of the impedance of this device in silicon and discuss the physics and device performance. We also evaluate the dynamic range and sensitivity of the wireless photoimpedance sensors and show their advantages for wireless sensing applications compared to more conventional light sensors.
Influence of substrate temperature and post annealing on morphology and magnetic properties of pulsed laser deposited Fe50-Ni50 films.
Authors: Ibrahim Sally A. , Fialkova Svitlana , Mensah-Darkwa Kwadwo , Yarmolenko Sergey , Kumar Dhananjay
Published: October 2014

As the need for smaller data storage devices in the market continues to grow, the study of new combinations of self-assembled magnetic nanoparticles/films is greatly needed. In this research, Fe50-Ni50 films were synthesized using a Pulsed Laser Deposition technique. The films were analyzed using scanning electron microscopy (SEM), atomic force microscopy (AFM) and physical properties measurement system (PPMS). Films were deposited from Fe-Ni alloy target (50%-50% composition), deposition was conducted in vacuum, at substrate temperatures varying from liquid nitrogen temperature -196°C to 600°C. The films were annealed in a vacuum chamber at 600°C for 1 hour. The study reveals that the substrate temperature has significant effect on the structure of the films and their magnetic properties. It was shown that additional thermal treatment improved the quality of films in terms of narrow grain size distribution. Magnetic properties were also found to improve significantly after post annealing process.
Assembly and Characterization of Protein Resistant Planar Bilayers in PDMS Microfluidic Devices
Authors: Phillips K. Scott , Cheng Quan
Published: October 2014

We report a method using vesicle fusion techniques that result in long-standing hydrophilic and protein-resistant PDMS surfaces. The PDMS was oxidized in plasma followed by treatment with various concentrations of phospholipid vesicles to form planar bilayer membranes in the microchannels. Contact angle measurements showed that a freshly oxidized hydrophilic surface began hydrophobic recovery immediately, but PC (phosphatidylcholine) treated surfaces exhibited prolonged hydrophilic properties up to two hours after bilayer modification, and cationic DOPC+ treated surfaces had a contact angle of ∼70. FRAP experiments confirmed fusion of vesicles to form bilayers with lateral mobility. Protein adsorption studies in microchannels showed 2-3 orders of magnitude decrease in fluorescence from non-specific adsorption of dye-conjugated avidin and BSA. Coulombic interaction was found to play an important role in determining the amount of non-specific adsorption. Dehydration of the membranes resulted in increased protein adsorption after rehydration for PC but not for the synthetic lipid DOPC+, which has a positively charged headgroup.
Hydrogen Storage in Magnesium-Based Alloys
Authors: Schwarz R.B.
Published: October 2014

Magnesium can reversibly store about 7.7 wt% hydrogen, equivalent to more than twice the density of liquid hydrogen. This high storage capacity, coupled with a low price, suggests that magnesium and magnesium alloys could be advantageous for use in battery electrodes and gaseous-hydrogen storage systems. The use of a hydrogen-storage medium based on magnesium, combined with a fuel cell to convert the hydrogen into electrical energy, is an attractive proposition for a clean transportation system. However, the advent of such a system will require further research into magnesium-based alloys that form less stable hydrides and proton-conducting membranes that can raise the operating temperature of the current fuel cells.

Following the U.S. oil crisis of 1974, research into alternative energy-storage and distribution systems was vigorously pursued. The controlled oxidation of hydrogen to form water was proposed as a clean energy system, creating a need for light and safe hydrogen-storage media. Extensive research was done on inter-metallic alloys, which can store hydrogen at densities of about 1500 cm3-H2 gas/ cm3-hydride, higher than the storage density achieved in liquid hydrogen (784 cm3/cm3 at –273°C) or in pressure tanks (˜200 cm3/cm3 at 200 atm). The interest in metal hydrides accelerated following the development of portable electronic devices (video cameras, cellular phones, laptop computers, tools, etc.), which created a consumer market for compact, rechargeable batteries. Initially, nickel-cadmium batteries fulfilled this need, but their relatively low energy density and the toxicity of cadmium helped to drive the development of higher-energy-density, less toxic, rechargeable batteries.
Development of water supply and sewage systems in rural areas of Małopolskie and Podkarpackie Voivodeships
Authors: Bergel Tomasz , Chmielowski Krzysztof , Pawełek Jan
Published: October 2014

The paper presents the development of water supply networks and sewage systems in rural areas
of Małopolskie and Podkarpackie Voivodeships in the Polish context. The scope of the thesis
includes the analyses of length of water supply networks and sewage systems, number of people
using them, number of water and sewage connections and volume of used water and volume of
discharged sewage. The results of the study were presented in the graphs. The research material was taken from the reports on municipal infrastructure published by The Polish Central
Statistical Office (GUS) for 2002–2012 and Local Data Bank (BDL) for 1995–2001. Though there
has been a significant improvement in water supply and sewage systems, Poland will have great
difficulty in meeting the requirements concerning their development in rural areas by 2015.