bluuebunny/crossref_metadata_2025 huggingface dataset:
Dual‐frequency ultrasound effect on structure and properties of sweet potato starch
Authors: Zheng Jie , Li Qian , Hu Aijun , Yang Lin , Lu Jing , Zhang Xiaoqinq , Lin Qiuqian
Published: October 2014

Effects on the structure and properties of sweet potato starch under single frequency ultrasound of 25, 80 kHz and dual‐frequency ultrasound of 25 and 80 kHz were investigated at the same treating conditions else. Dents and pores were found by SEM at the surface of starch with both ultrasounds. Starch–iodine complex analysis showed above ultrasounds destroyed amylopectin and starch chains. FT‐IR indicated that with ultrasonic treatments, the functional groups of starch were not destroyed, but its crystal structure was damaged. As a result, its crystalline index decreased. Brabender curves showed that the peak viscosity of starch with dual‐frequency ultrasound was 14.09% lower than that of the native starch. In addition, the solubility and transmittance of starch increased by ultrasound, and the solubility went up as ultrasonication time was increased. It reached the maximum when the starch was treated for 60 min by dual‐frequency ultrasound, which increased by 2.69% compared to that of native starch. The starch being treated by dual‐frequency ultrasound for 30 min showed maximum transmittance, increasing it by 5.1% compared to the native starch; however, continuously increasing ultrasonic treatment resulted in a decrease of transmittance. Therefore, compared to single frequency ultrasound, dual‐frequency ultrasonic treatment caused more obvious changes to the structure and properties.
Thermal degradation and stability of starch under different processing conditions
Authors: Liu Xingxun , Wang Yanfei , Yu Long , Tong Zhen , Chen Ling , Liu Hongsheng , Li Xiaoxi
Published: October 2014

The objectives of this paper are to review the thermal degradation and stability of starch and starch‐based materials, including both fundamental sciences such as detecting techniques, the effect of amylose/amylopectin content in starches and starches modifications, as well as the effect of different processing environments, such as an open or sealed system, and shearless or shear stress conditions. The decomposition temperature of starches was increased with increasing amylopectin content in an open system. In the open system, the initial water content did not affect the decomposition temperature because all water had evaporated from samples prior to reaching the decomposition temperature. Two decomposition temperatures were observed in the sealed system: the first at lower temperature represents long chain scission; and the second at higher temperature involves decomposition of glucose ring. In the sealed system, the first degradation was increased with increasing amylopectin content. There is no observable difference of the second degradation for the samples containing different amylose/amylopectin ratios. The higher the moisture content is, the lower the second decomposition temperature is detected in the sealed system. Significant shear degradation was observed in amylopectin component of starch, while high amylose starch proved less sensitive to shear stress. The achievements in this area have increased the knowledge of polymer science, in particular to understand the degradation of natural polymers.
Influence of glycerol content on the electrical properties of potato starch films
Authors: Ayala Valencia Germán , Henao Ana Cecilia Agudelo , Zapata Rubén Antonio Vargas
Published: October 2014

Effects of glycerol (G) and temperature (T) on the electrical properties of potato starch (PS) films were investigated by impedance spectroscopy measurements in the radio frequency range (20 Hz–3 MHz). The membranes were prepared by a solution casting method with weight fraction glycerol/potato starch (G/PS) = 0.1, 0.3, and 0.5 and characterized by DSC, FTIR, and moisture content measurements. The dc‐conductivity (σ0) of all compositions increases with the glycerol concentration and temperature, reaching the value of 5.2 × 10−5/Scm at 423 K, for G/PS = 0.5. The real part of the conductivity shows power–law frequency dependence (fn, n ≈ 0.98) at frequencies higher than a crossover frequency (fp). The imaginary part of the electric modulus plots shows non‐Debye asymmetrical peaks at about the frequency fp and it is characterized by a “stretched” exponential parameter β ≈ 0.8. The temperature dependence of σ0, fp (both showing an Arrhenius‐type behavior) and DSC data shows a phase boundary at about 353 K for all compositions. Results are discussed in terms of correlation effects in ion motion that takes place in a separate second phase in the G/PS films with composition G/H2O.
Starch composition and its granules distribution in wheat grains in relation to post‐anthesis high temperature and drought stress treatments
Authors: Lu Hongfang , Wang Chenyang , Guo Tiancai , Xie Yingxin , Feng Wei , Li Shuyi
Published: October 2014

High temperature (HT) and drought stress (DS) pose serious limitations to wheat (Triticum aestivum L.) grain development, which strongly influences grain yield and quality. In this study, we investigated changes in starch characteristics and starch granules of the high‐yielding winter wheat cultivar Zhengmai 366 in response to HT and DS, both alone and in combination. HT, DS and the combination of these stressors led to a significant reduction in the proportion of A‐type starch granules (>9.9 µm) to B‐type starch granules (<9.9 µm), and the effects of HT and DS were significantly additive. The volume proportion of A‐type starch granules (>9.9 µm) was positively correlated with the contents of AM, AP and starch as well as the grain yield (thousand grains weight) and was negatively correlated with the ratio of AM to AP, whereas there was a contrary correlation between the volume proportion of B‐type starch granules (<9.9 µm) and these values. HT, DS and HT plus DS led to a significant reduction in the content of AP and starch and grain yield, but these treatments had less of an impact on AM content. DS reduced the size of the small starch granules, while HT reduced the size of the large granules. The changes in morphology and size distribution of starch granules led to a reduction in starch content under both stress conditions, consequently reducing grain yield. HT plus DS had a much greater influence on starch characteristics and yield than HT or DS alone.
Radiation synthesis and characterization of starch‐based hydrogels for removal of acid dye
Authors: Mahmoud Ghada A. , Abdel‐Aal Samia E. , Badway Nagwa A. , Abo Farha Samia A. , Alshafei Esraa A.
Published: October 2014

A series of hydrogels based on starch, acrylic acid (AAc) and 2‐hydroxyethyl methacrylate (HEMA), namely AAc/starch and AAc/HEMA/starch hydrogels were synthesized by gamma radiation and used to adsorb acid fast red dye from aqueous solution. Alkali treatment of AAc/starch hydrogels to improve their ionic character was evaluated. The structure and surface morphology of prepared hydrogels were confirmed by Fourier transfer infrared spectra and SEM, respectively. The results indicated that the diffusion of water into the hydrogels pertains a non‐Fickian character. The swelling equilibrium for AAc/starch and NaAc/starch hydrogels was obtained after 10 h whereas for AAc/HEMA/starch hydrogels after 5 h. The effects of the medium pH, initial dye concentration and temperature on the adsorption were studied. The adsorption capacity increases with increasing dye concentration and decreasing medium pH. The increase of temperature leads to higher adsorption capacity for AAc/starch and NaAc/starch hydrogels but lower adsorption capacity for AAc/HEMA/starch hydrogels.
Partially oxidized potato starches from bromide‐free TEMPO‐mediated reaction: characterization of monosaccharide composition
Authors: Ponedel'kina Irina Yu. , Araslanova Dilyara I. , Tyumkina Tatyana V. , Lukina Elena S. , Odinokov Viktor N.
Published: October 2014

Partially oxidized starches were obtained by oxidation of water‐soluble potato starch with the NaOCl/2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO) system in the absence of bromide in aqueous solutions at pH 10.2. Monosaccharide composition of the oxidized starches was studied by acid–base titration and NMR spectroscopy, and it was characterized by a content of B units with carboxyl groups (7–73 mol%), C units with C‐6‐aldehyde hydrate groups (5–37%), and non‐oxidized A units (20–88%). The feature of bromide‐free TEMPO‐mediated oxidation of starch was the formation of a significant amount of C units. In addition to monosaccharide composition, compositional heterogeneity of a starch sample with 73% of B units was described by the distribution of triad sequences BBB (54 mol%), ABA (20%), AAB + BAA (12%) and BAB (14%), which were quantified by NMR spectroscopy.
Immobilization of α‐amylase via adsorption onto bentonite/chitosan composite: Determination of equilibrium, kinetics, and thermodynamic parameters
Authors: Baysal Zübeyde , Bulut Yasemin , Yavuz Murat , Aytekin Çetin
Published: October 2014

Immobilization of α‐amylase onto bentonite/chitosan (BC) composite was studied via adsorption. The composite was characterized by FTIR, SEM, and surface area measurements. The effect of different factors such as, pH, temperature, initial enzyme concentration, and various thermodynamic parameters was determined. The maximum α‐amylase adsorption capacity of the BC composite was determined as 64 mg/g at 0.8 mg/mL enzyme concentration. The activity of the immobilized enzyme was measured under varying experimental conditions. The highest enzyme activity for free and immobilized enzyme was determined at 30 and 35°C in 0.1 M phosphate buffer at pH 7.0. The effect of substrate concentration on enzyme activity of free and immobilized enzymes showed a good fit to the Lineweaver–Burk plots. Michaelis constant, Km, for the immobilized α‐amylase was found to be higher than for the free enzyme. The adsorption isotherm was modeled by the Langmuir equation.
Synthesis and characterisation of starch tartrate and its application as novel disintegrant in telmisartan tablets
Authors: Assaleh Fathi H. , Katakam Prakash , Botcha Ramesh , Chandu Babu Rao , Adiki Shanta Kumari
Published: October 2014

The aim of the present study was to synthesize potato starch (PS) derivatives of tartaric acid (TA) under semi‐dry conditions and to evaluate the physicochemical properties as per official compendia requirements. Starch tartrate (ST) was synthesized by reacting PS (St–OH) and TA in semi‐dry condition using sodium hypophosphite (SHP) as a catalyst. Further we have applied its use as disintegrant in directly compressed telmisartan tablets. The microscopic, spectroscopic (FTIR), thermal (DSC) and crystallographic (XRD) studies confirmed the formation of ST. No gelling was observed at 100°C but it was converted to a clear solution with a swelling index of 1.666 times. ST was found to have suitable compression properties required for directly compressible tablets. The tablets formulated employing ST (5–15% w/w) as disintegrant gave rapid disintegration and dissolution rates compared to those prepared using commercial superdisintegrants (sodium starch glycolate and crosscarmellose sodium). The optimized formulation showed disintegration time of 31 ± 3 s which is found superior to that of others. It is concluded that the synthesized ST could be employed as a promising disintegrant in dispersible tablet formulations.
Physicochemical and rheological properties of starches substituted with type 4 resistant starch (cross‐linked corn starch)
Authors: Jun Soo Jin , Lee Kwang Yeon , Lee Suyong , Lee Hyeon Gyu
Published: October 2014

The physicochemical and rheological properties of native starch (corn (CS), rice (RS), potato (PS), tapioca (TS), and wheat (WS)) from different sources substituted with RS type 4 (RS4) at different concentrations (0, 20, and 50%) were determined. Swelling power and solubility of all native starch–RS4 mixtures proportionally decreased with the increase of RS4 concentration. Also, the peak viscosity and breakdown of starch–RS4 mixture decreased with increasing concentrations of the RS4 used. However, the setback viscosity decreased significantly for CS‐RS4, TS‐RS4, and WS‐RS4, but it remained unchanged for PS‐RS4. All native starch–RS4 mixtures exhibited decreased viscosity with increasing RS4, which could be well characterized by the Power‐law model. Furthermore, dynamic oscillatory tests indicated that the native starch and RS4 mixtures exhibited less elastic properties with more frequency dependence, compared to native starch alone. Hardness for CS‐RS4, RS‐RS4, PS‐RS4, and WS‐RS4 gel decreased with increased storage time, whereas TS‐RS4 did not.
Microwave‐assisted synthesis and characterization of acetylated corn starch
Authors: Zhang Hao , Wang Rui , Wang Jiankun , Dong Yongchun
Published: October 2014

In this study, native corn starch (NCS) was acetylated by a microwave‐assisted method using vinyl acetate as an acetylating agent and potassium carbonate as a catalyst. Acetylated corn starch (ACS) was characterized by Fourier‐transform infrared spectroscopy, SEM, and XRD. The optimum conditions of acetylation (i.e., reaction temperature, exposure time, and catalyst concentration) were assessed. The physicochemical properties of ACS including swelling power, solubility, intrinsic viscosity, apparent viscosity, paste clarity, and syneresis were studied. Furthermore, the adhesion property and sizing performance were evaluated. The results revealed that the physicochemical properties of ACS were improved compared with those of NCS. The adhesion force of ACS to polyester/cotton fibers increased significantly; the sizing properties of ACS were better than those of NCS. ACS, which has potential applications in the textile industry, is an ideal substitute for polyvinyl alcohol.
Characteristics and structure of starch isolated from triticale
Authors: Makowska Agnieszka , Szwengiel Artur , Kubiak Piotr , Tomaszewska‐Gras Jolanta
Published: October 2014

Triticale is a hybrid obtained by crossing wheat with rye. One of the factors limiting its application into food industry is still a lack of knowledge about this cereal. The aim of this study was to characterize and compare features of triticale starch obtained from grain of five new Polish triticale varieties: Madilo, Baltiko, CHD 3012/99, Pizarro and Fredro. Starch content in grain of analyzed cultivars varied in narrow range, while differences of falling number values, in spite of the same growing condition, varied more significantly. All the investigated triticale starches had a bimodal size distribution of granules. This was confirmed by both laser diffraction methods and scanning electron microscopy. Tested starches differed in terms of their amylose content and particle size distribution, thermal and pasting properties, as well as molecular weights. Starches of higher molecular mass (Mw) underwent gelatinization at higher temperature, according to DSC analysis. Values of pasting temperatures recorded by RVA were higher than those obtained by DSC. Relative proportion of A‐type to B‐type starch granules affected pasting properties measured by RVA. Starches of higher Mw underwent gelatinization at higher temperature. Tested triticale starches did not differ much in terms of hydrodynamic properties, offset and peak temperatures (DSC). Differences between samples show that physicochemical properties and the structure of triticale starch are variety‐dependent. PCA analysis indicated that starches obtained from Madilo and CHD 3099/12 as well as Baltiko and Fredro form separate groups with similar characteristics. Starch of cv. Pizarro differs significantly from those of the other cultivars.
The molecular and supermolecular structure of common cattail (Typha latifolia) starch
Authors: Kurzawska Agata , Górecka Danuta , Błaszczak Wioletta , Szwengiel Artur , Paukszta Dominik , Lewandowicz Grażyna
Published: October 2014

Common cattail (Typha latifolia) is a wetland plant that is widespread all over the world. All of its morphological parts are edible, but the rhizome is the most valuable. Its starch content can be up to 70% of the dry mass; however, its structure and functionality have not yet been described. The aim of this study was to characterise the structure of cattail rhizome starch. The rhizome of common cattail was harvested in the spring from a natural pond. The starch was isolated by grinding and washing away the fibre fraction. Sonication was used to disintegrate the cell walls. The structure of starch granules was studied using the scanning electron microscopy (SEM) and wide angle X‐ray scattering method (WAXS). The molecular mass distribution of the starch macromolecules was analysed with gel permeation chromatography using triple detection and compared to results of corn and potato starches. The granules of the cattail starch were predominantly round shaped and had a typical Gaussian distribution of size characterised by a mode value of 9 µm. The WAXS investigation proved that the granules had a C type crystal structure, which was a combination of A and B polymorphs contributing 28.3 and 71.7%, respectively. The cattail starch contained 32% amylose. Its molecular mass was significantly higher than potato starch but slightly lower than corn starch. The molecular mass of cattail amylopectin was between corn and potato starch. Its structure was the most branched compared to all the starches investigated.
The use of hot‐melt extruded corn starch matrices as drug carrier systems: A thermophysical characterization
Authors: Kipping Thomas , Trindade Rita , Rein Hubert
Published: October 2014

Corn starches with varying ratios of amylose to amylopectin are plasticized by hot‐melt extrusion. The nearly amorphous matrices are loaded with different model drug substances to evaluate the interaction of plasticized starch and active pharmaceutical ingredients with varying solubility. Two different thermal analytical methods are applied to provide a detailed insight into the thermal behavior of the material: Differential scanning calorimetry (DSC) and dymamic mechanical thermal analysis (DMTA). A comparison of both methods provides a more detailed understanding of the interaction of different constituents in the range of the glass transition temperature (Tg). Activation energies of Tgs can be determined by applying Arrhenius equation. Residual moistures of the unprocessed starches and the extruded products are compared using thermogravimetric analysis. Extrusion processing causes no changes of the dynamic vapor sorption behavior in the targeted storage conditions. Crystalline structure of the matrices has been studied via XRD. Recrystallization effects can be observed for high amylose corn starches, whereas for waxy corn starches no recrystallization occurs. The crystal state of the final product during API addition can be strongly linked to corresponding solubility. Drug loading with phenazone, a high soluble API, leads to the formation of a solid solution, whereas addition of the more lipophilic acetaminophen results in the formation of a solid dispersion.
Acid modification of wheat, potato, and pea starch applying gentle conditions—impacts on starch properties
Authors: Ulbrich Marco , Natan Cindy , Flöter Eckhard
Published: October 2014

Acid‐thinned wheat, potato, and pea starch products were systematically prepared applying gentle conditions with variation of acid type (HCl and H2SO4), acid concentration (0.36 and 0.72 N in a 40% (w/w) suspension) as well as hydrolysis time (4 and 24 h). Starch granule properties as well as molecular and rheological characteristics in the solution state were analyzed and the impact of all parameters varied was found to be immense. Carbohydrate solubilization of wheat and potato starch was significantly higher compared to pea starch. Noteworthy progress in solubilization was found when hydrolyzed with HCl, and with increasing acid concentration and increasing hydrolysis time by trend. The hydrolysis affected the reduction of the hot paste viscosity most dominant in the first period of treatment (0–4 h), however, size exclusion chromatography‐multi angle laser light scattering (SEC‐MALS) analysis revealed a more prominent molecular degradation during the second period (4–24 h). This observation led to the interpretation that the molecular degradation in the initial phase results particularly in “debranching” of the high molar mass amylopectin fraction and lower hot paste viscosity. Continued hydrolysis with significant reduction of the molecular size, however, had reduced impact on further lowering of viscosity. SEM micrographs displayed intact pea starch granules with unchanged surface after hydrolysis, whereas wheat and potato starch granules were visibly affected with damage not evenly distributed but a variation over the granule population. Granular wheat and potato starch exhibited significantly enhanced particle size after short period modification measured in water. However, this was found eliminated at extended hydrolysis time. Reasons were hydrolysis induced molecular rearrangement resulting in better crystalline packing on the amorphous/crystalline threshold reducing the ability to swell, and the progress in granular erosion. That was in line with changed swelling characteristics determined using DSC. The study gave evidence for strong impact of acid hydrolysis on functional properties like water binding.
Mentorship in Surgical Training: Current Status and A Needs Assessment for Future Mentoring Programs in Surgery
Authors: Sinclair P. , Fitzgerald J. E. F. , Hornby S. T. , Shalhoub J.
Published: October 2014

Aims

Mentoring has been used extensively in the business world to enhance performance and maximise potential. Despite this, there is currently a paucity of literature describing mentoring for surgical trainees. This study examined the current extent of mentoring and investigated future needs to support this.

Methods

An electronic, 47‐item, self‐administered questionnaire survey was distributed via national and regional surgical mailing lists and websites through the Association of Surgeons in Training and Specialty Associations in the UK and Republic of Ireland.

Results

Overall, 565 fully completed responses were received from trainees in all specialties, grades and training regions. A total of 48.7 % of respondents reported that they have a surgical mentor, with no significant gender difference (p = 0.65). Of respondents, 52.5 % considered their educational supervisor and 45.5 % their current consultant as mentors. Modal duration of mentoring relationships was 1–2 years (24.4 %). A total of 90.2 % of mentors were in the same specialty, 60.7 % in the same hospital, and 88.7 % in the same training region. Mentors covered clinical and professional matters (99.3 %) versus pastoral and non‐clinical matters (41.1 %). Mentoring was commonly face to face or via email and not documented (64.7 %). Of the 51.3 % without a mentor, 89.7 % would like a clinical mentor and 51.0 % a pastoral mentor (p < 0.001). Priority mentoring areas included career progression (94.9 %), research (75.2 %), clinical skills (66.9 %) and clinical confidence (58.4 %). A total of 94.3 % would be willing to act as a peer mentor. Only 8.7 % had received mentoring training; 83 % wish to undertake this.

Conclusions

Less than half of surgical trainees identified a mentor. The majority want mentoring on professional topics during their training and would additionally be willing to peer‐mentor colleagues, although few have received training for this. Despite an identified need, there is currently no structure for organising this and little national provision for mentoring.
Management Guidelines for Penetrating Abdominal Trauma
Authors: Biffl Walter L. , Leppaniemi Ari
Published: October 2014

Introduction

The optimal management of patients with penetrating abdominal injuries has been debated for decades, since mandatory laparotomy (LAP) gave way to the concept of “selective conservatism.”

Materials and Methods

A comprehensive literature review was performed and summarized.

Results

A proposed management guideline for patients with penetrating abdominal trauma was created.

Conclusion

Indications for immediate laparotomy (LAP) include hemodynamic instability, evisceration, peritonitis, or impalement. Selective nonoperative management of stable, asymptomatic patients has been demonstrated to be safe. Adjunctive diagnostic testing—ultrasonography, computed tomography, local wound exploration, diagnostic peritoneal lavage, laparoscopy—is often used in an attempt to identify significant injuries requiring operative management. However, prospective studies indicate that these tests frequently lead to nontherapeutic LAP, and are not cost‐effective.
Impact of the Route of Reconstruction on Post‐operative Morbidity and Malnutrition after Esophagectomy: A Multicenter Cohort Study
Authors: Yamasaki Makoto , Miyata Hiroshi , Yasuda Takushi , Shiraishi Osamu , Takahashi Tsuyoshi , Motoori Masaaki , Yano Masahiko , Shiozaki Hitoshi , Mori Masaki , Doki Yuichiro
Published: October 2014

Background

Reconstruction after esophagectomy is mainly performed through the retrosternum (RS) or posterior mediastinum (PM). However, the best approach is not clear. This study aimed to assess the impact of the route of gastric conduit reconstruction, after esophagectomy for esophageal squamous cell carcinoma (ESCC), on post‐operative outcomes.

Methods

We analyzed 298 patients who underwent radical esophagectomy for ESCC at three high volume centers between 2008 and 2009. Among them, the RS was selected in 166 patients and PM in 118; while, the antethoracic route was used in 14 patients. Post‐operative morbidity, mortality, and long‐term outcome were compared.

Results

There were no differences between patients of the two routes with respect to operative blood loss (RS: 753 ± 519, PM: 748 ± 414 g) and post‐operative complications, including pulmonary problems (RS: 15 %, PM: 10.2 %) and anastomotic leakage (RS: 9.0 %, PM: 5.1 %); although, the operating time (RS: 566 ± 97, PM: 472 ± 79 min; p < 0.0001) was shorter in the PM group than the RS group. The percentage weight loss after surgery was significantly less in the PM group than the RS group at 1 year (8.6 vs. 11.1 %; p = 0.025); although, the percentage at discharge was not different between the groups (PM: 4.9 %, RS: 6.3 %; p = 0.072). Multivariate analysis identified pre‐operative body weight and the reconstruction route as significant and independent factors associated with 1‐year weight loss.

Conclusions

The results indicate gastric tube reconstruction through the posterior mediastinal route after esophagectomy may relieve post‐operative 1‐year malnutrition without increasing post‐operative complications.
The Utility of the Kampala Trauma Score as a Triage Tool in a Sub‐Saharan African Trauma Cohort
Authors: Haac Bryce , Varela Carlos , Geyer Andrew , Cairns Bruce , Charles Anthony
Published: October 2014

Background

Trauma scoring systems have been developed to assess injury severity and may have triage potential. We sought to evaluate the ability of the Kampala trauma score (KTS) to assess injury severity and its potential as an outcome predictive tool in Malawi.

Methods

This is a prospective cohort study of trauma patients presenting to Kamuzu Central Hospital in 2012. We recorded admission KTS and Revised trauma score (RTS), emergency department disposition, and hospital length of stay (LOS) and survival. Logistic regression and ROC curve analyses were used to compare the KTS to the widely accepted RTS.

Results

15,617 patients presented with trauma. 2,884 (18 %) were admitted, of which 2,509 (95 %) survived. The mean admission KTS was 14.5 ± 0.6, and RTS was 11.9 ± 0.3. For KTS and RTS, the odds of admission with each increment increase in score was 0.44 and 0.3, respectively. Similarly, odds of mortality is 0.48 and 0.36. Neither KTS (p = 0.96, ROC area 0.5) nor RTS (p = 0.25, ROC area 0.5) correlated significantly with hospital LOS. KTS and RTS performed equally well as predictors of mortality, but KTS was a better predictor of need for admission (KTS ROC area 0.62, RTS ROC area 0.55, p < 0.001).

Conclusions

Both the KTS and RTS were significantly associated with need for admission and final outcome on logistic regression analysis; however, they may not be strong enough predictors to merit their use as a screening tool in our setting.
Outcomes of Open Reduction and Internal Fixation of Acute Proximal Pole Scaphoid Fractures
Authors: Brogan David M. , Moran Steven L. , Shin Alexander Y.
Published: October 2014

Background

Proximal pole scaphoid fractures are less common than waist fractures, and successful management can be difficult. We hypothesize that time to union is increased by delays in surgical fixation, greater initial displacement, and higher energy mechanisms of injury.

Methods

A retrospective review was conducted of all patients undergoing open reduction internal fixation (ORIF) of acute proximal pole scaphoid fractures at our institution over a 19-year period. A review of clinical as well as radiographic data was undertaken. The mechanism of injury, patient demographics, timing of surgery, initial displacement, fixation method, smoking status, and lunate morphology were recorded. Functional outcome measures were recorded when available. Univariate analysis using Kaplan-Meier survival curves was performed.

Results

A total of 10 out of 23 patients (43 %) showed evidence of union at 14 weeks post-injury. Rates of early union were higher in non-displaced fractures (70 %) when compared to displaced fractures (23 %). Similarly, fractures sustained via low energy mechanisms had a higher rate of early union compared to high energy mechanisms (69 versus 10 %). A delay in ORIF did not appear to influence rate of union.

Conclusions

Initial displacement and mechanism of injury have the most significant effects on early rates of union. Delay in ORIF of up to 28 days did not affect the rate of initial union, but the authors recommend early fixation of these fractures to prevent further displacement. Patients with widely displaced fractures or those with high energy mechanisms should be counseled regarding prolonged healing time. Level of Evidence: IV—therapeutic
N‐Stearoylethanolamine Restores Pancreas Lipid Composition in Obesity‐Induced Insulin Resistant Rats
Authors: Onopchenko Oleksandra V. , Kosiakova Galina V. , Oz Murat , Klimashevsky Vitaliy M. , Gula Nadiya M.
Published: October 2014

This study investigates the protective effect of N‐stearoylethanolamine (NSE), a bioactive N‐acylethanolamine , on the lipid profile distribution in the pancreas of obesity‐induced insulin resistant (IR) rats fed with prolonged high fat diet (58 % of fat for 6 months). The phospholipid composition was determined using 2D thin‐layer chromatography. The level of individual phospholipids was estimated by measuring inorganic phosphorus content. The fatty acid (FA) composition and cholesterol level were investigated by gas–liquid chromatography. Compared to controls, plasma levels of triglycerides and insulin were significantly increased in IR rats. The pancreas lipid composition indicated a significant reduction of the free cholesterol level and some phospholipids such as phosphatidylcholine (PtdCho), phosphatidylethanolamine (PtdEtn), phosphatidylinositol (PtdIns), phosphatidylserine (PtdSer) compared to controls. Moreover, the FA composition of pancreas showed a significant redistribution of the main FA (18:1n‐9, 18:2n‐6, 18:3n‐6 and 20:4n‐6) levels between phospholipid, free FA, triglyceride fractions under IR conditions that was accompanied by a change in the estimated activities of Δ9‐, Δ6‐, Δ5‐desaturase. Administration of N‐stearoylethanolamine (NSE, 50 mg/kg daily per os for 2 weeks) IR rats triggered an increase in the content of free cholesterol, PtdCho and normalization of PtdEtn, PtdSer level. Furthermore, the NSE modulated the activity of desaturases, thus influenced FA composition and restored the FA ratios in the lipid fractions. These NSE‐induced changes were associated with a normalization of plasma triglyceride content, considerable decrease of insulin and index HOMA‐IR level in rats under IR conditions.
Childbearing Postponement and Child Well-being: A Complex and Varied Relationship?
Authors: Goisis Alice , Sigle-Rushton Wendy
Published: October 2014

Over the past several decades, U.S. fertility has followed a trend toward the postponement of motherhood. The socioeconomic causes and consequences of this trend have been the focus of attention in the demographic literature. Given the socioeconomic advantages of those who postpone having children, some authors have argued that the disadvantage experienced by certain groups would be reduced if they postponed their births. The weathering hypothesis literature, by integrating a biosocial perspective, complicates this argument and posits that the costs and benefits of postponement may vary systematically across population subgroups. In particular, the literature on the weathering hypothesis argues that, as a consequence of their unique experiences of racism and disadvantage, African American women may experience a more rapid deterioration of their health which could offset or eventually reverse any socioeconomic benefit of postponement. But because very few African American women postpone motherhood, efforts to find compelling evidence to support the arguments of this perspective rely on a strategy of comparison that is problematic because a potentially selected group of older black mothers are used to represent the costs of postponement. This might explain why the weathering hypothesis has played a rather limited role in the way demographers conceptualize postponement and its consequences for well-being. In order to explore the potential utility of this perspective, we turn our attention to the UK context. Because first-birth fertility schedules are similar for black and white women, we can observe (rather than assume) whether the meaning and consequences of postponement vary across these population subgroups. The results, obtained using linked UK census and birth record data, reveal evidence consistent with the weathering hypothesis in the United Kingdom and lend support to the arguments that the demographic literature would benefit from integrating insights from this biosocial perspective.
Shareholder value implications of service failures in triads: The case of customer information security breaches
Authors: Modi Sachin B. , Wiles Michael A. , Mishra Saurabh
Published: October 2014

The rise in front‐end service outsourcing in recent years, despite its advantages, has also exposed buyer firms to unique challenges. One of the most salient risks for buyer firms in service triads is service failure due to the service provider. Indeed such service failures may be more costly for firms due to the greater relational and operational costs that may arise from the presence of the third‐party provider. Yet, neither the services literature nor extant operations literature on service triads has paid much attention to the financial consequences to the buyer firm – i.e., service risks – of such service failures in triads. To fill this gap, we investigate the financial penalty of service failures due to the service provider using the event study methodology and a sample of 146 customer information security breaches as our empirical context. Analysis of the abnormal returns reveals that service failures due to the front‐end service provider lead to greater shareholder losses than such failures due to the buyer firm. This provides important new insight into the financial risks arising from outsourcing front‐end services. Further, we investigate the ability of the buyer firm's employee and financial resources to temper these shareholder losses. We find that buyer firm employee productivity can moderate the greater financial penalty associated with such triadic service failures but that buyer firm leverage tends to not have such a mitigating effect. This provides new guidance for theory and practice regarding how buyer firms can position themselves to buffer the financial risks arising from service failures due to front‐end service providers.
Outsourcing customer support: The role of provider customer focus
Authors: Wuyts Stefan , Rindfleisch Aric , Citrin Alka
Published: October 2014

An increasing number of firms are outsourcing customer support to external service providers. This creates a triadic setting in which an outsourcing provider serves end customers on behalf of its clients. While outsourcing presents an opportunity to serve customers, service providers differ in their motivation and ability to fulfill customer needs. Prior research suggests that firms with a strong customer focus have an intrinsic motivation to address customer needs. We suggest that in an outsourcing context, this intrinsic motivation does not suffice. Using a Motivation–Opportunity–Ability framework, we posit that the effect of a provider's customer focus will be moderated by a set of relational, firm, and customer characteristics that affect its ability to serve end customers. We test our conceptualization among 171 outsourcing clients from the Netherlands and then validate these results among 135 Indian outsourcing providers. The findings reveal that customer‐focused providers achieve higher levels of customer need fulfillment but this effect is contingent on their ability to serve end customers. In particular, customer‐focused providers more effectively fulfill customer needs when clients and providers share close relational ties, when clients also have a high level of customer focus, and when end customer needs exhibit a low degree of turbulence. In addition, we find that, in turbulent markets, equipment‐related services offer greater opportunity for effective customer need fulfillment than other outsourced services.
Exercise-Associated Hyponatremic Encephalopathy in an Endurance Open Water Swimmer
Authors: Rogers Ian R. , Grainger Stephen , Nagree Yusuf
Published: October 2014

Exercise-associated hyponatremia and its more serious form, known as exercise-associated hyponatremic encephalopathy, are recognized as some of the most important medical problems seen in a variety of different forms of endurance exercise. We describe a case of exercise-associated hyponatremic encephalopathy presenting as altered conscious state and seizures in a woman who had completed a 20-km open ocean swim. Her serum sodium measured approximately 1 hour after her seizure was 119 mmol/L on point-of-care testing. With ongoing critical care support and the use of hypertonic saline, she was able to be extubated the next day, neurologically intact, and ultimately was discharged from hospital without neurological sequelae. This case emphasizes both the importance of considering exercise-associated hyponatremic encephalopathy as a cause of neurological impairment in all athletes and the pivotal role of hypertonic saline in the treatment of this condition.
Logarithmic temperature profiles in the bulk of turbulent Rayleigh–Bénard convection for a Prandtl number of 12.3
Authors: Wei Ping , Ahlers Guenter
Published: October 2014

We report measurements of logarithmic temperature profiles $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}\varTheta (z,r) = A(r)\times \ln (z/L) + B(r)$ in the bulk of turbulent Rayleigh–Bénard convection (here $\varTheta $ is a scaled and time-averaged local temperature in the fluid, $ z$ is the vertical and $r$ the radial position, and $L$ is the sample height). Two samples had aspect ratios $\varGamma \equiv D/L = 1.00$ and 0.50 (where $D=190\ \mathrm{mm}$ is the diameter). The fluid was a fluorocarbon with a Prandtl number of $\mathit{Pr} = 12.3$. The measurements covered the Rayleigh-number range $2\times 10^{10} \lesssim \mathit{Ra} \lesssim 2\times 10^{11}$ for $\varGamma = 1.00$ and $3\times 10^{11} \lesssim \mathit{Ra} \lesssim 2\times 10^{12}$ for $\varGamma = 0.50$. In contradistinction to what had been found for $\varGamma = 0.50$ and $\mathit{Pr} = 0.78$ by Ahlers et al. (Phys. Rev. Lett., vol. 109, 2012, art. 114501; J. Fluid Mech., 2014, in press), the measurements revealed no $\mathit{Ra}$ dependence of the amplitude $A(r)$ of the logarithmic term. Within the experimental resolution, the amplitude was also found to be independent of $\varGamma $. It varied with $r$ in a manner consistent with the function $A(\xi ) = A_1/\sqrt{2\xi - \xi ^2}$, where $\xi \equiv (R-r)/R$ with $R=D/2$ and $A_1 \simeq 0.0016$. The results for $A(r)$ are smaller than those obtained from experiments and direct numerical simulations (Ahlers et al., Phys. Rev. Lett., vol. 109, 2012, art. 114501) at similar values of $\mathit{Ra}$ for $\mathit{Pr} = 0.7$ and $\varGamma = \frac{1}{2}$ by a factor that depended slightly upon $\mathit{Ra}$ but was close to $2$.
A NEW RESULT ABOUT ALMOST UMBILICAL HYPERSURFACES OF REAL SPACE FORMS
Authors: ROTH JULIEN
Published: October 2014

In this short note, we prove that an almost umbilical compact hypersurface of a real space form with almost Codazzi umbilicity tensor is embedded, diffeomorphic and quasi-isometric to a round sphere. Then, we derive a new characterisation of geodesic spheres in space forms.
A NOTE ON ALMOST BALANCED BIPARTITIONS OF A GRAPH
Authors: HU XIAOLAN , ZHANG YUNQING , CHEN YAOJUN
Published: October 2014

Let $G$ be a graph of order $n\geq 6$ with minimum degree ${\it\delta}(G)\geq 4$. Arkin and Hassin [‘Graph partitions with minimum degree constraints’, Discrete Math. 190 (1998), 55–65] conjectured that there exists a bipartition $S,T$ of $V(G)$ such that $\lfloor n/2\rfloor -2\leq |S|,|T|\leq \lceil n/2\rceil +2$ and the minimum degrees in the subgraphs induced by $S$ and $T$ are at least two. In this paper, we first show that $G$ has a bipartition such that the minimum degree in each part is at least two, and then prove that the conjecture is true if the complement of $G$ contains no complete bipartite graph $K_{3,r}$, where $r=\lfloor n/2\rfloor -3$.
RADICAL RELATED TO SPECIAL ATOMS REVISITED
Authors: FRANCE-JACKSON HALINA , WAHYUNI SRI , WIJAYANTI INDAH EMILIA
Published: October 2014

A semiprime ring $R$ is called a $\ast$-ring if the factor ring $R/I$ is in the prime radical for every nonzero ideal $I$ of $R$. A long-standing open question posed by Gardner asks whether the prime radical coincides with the upper radical $U(\ast _{k})$ generated by the essential cover of the class of all $\ast$-rings. This question is related to many other open questions in radical theory which makes studying properties of $U(\ast _{k})$ worthwhile. We show that $U(\ast _{k})$ is an N-radical and that it coincides with the prime radical if and only if it is complemented in the lattice $\mathbb{L}_{N}$ of all N-radicals. Along the way, we show how to establish left hereditariness and left strongness of important upper radicals and give a complete description of all the complemented elements in $\mathbb{L}_{N}$.
A NOTE ON THE MORSE–NOVIKOV COHOMOLOGY OF BLOW-UPS OF LOCALLY CONFORMAL KÄHLER MANIFOLDS
Authors: YANG XIANGDONG , ZHAO GUOSONG
Published: October 2014

We prove a blow-up formula for Morse–Novikov cohomology on a compact locally conformal Kähler manifold.
Alignment or struggle? Exploring socio-demographic correlates of individual modernity in Chinese older people
Authors: BAI XUE
Published: October 2014

It is noteworthy that while modernisation, together with population ageing, has happened in Western countries for a rather long period of time, China must confront the challenges of an ageing population before it really becomes an advanced industrial society. Facing rapid societal changes, citizens may react differently to this process. By conducting questionnaire surveys with 445 elders in Wuhan, China, this study examines Chinese older adults' individual modernity modes and reveals its socio-demographic correlates. The results show that facing rapid changes in societal modernisation, participants have reacted differently to this process, with 23.8 per cent of Chinese older participants using an accommodation mode, 27.0 per cent using a resistance mode, 13.3 per cent using a withdrawal mode and 36.2 per cent using a coping mode. In addition, socio-demographic factors such as urban–rural residence, age, gender, socio-economic status, living arrangement and daily activities have been identified as significant correlates of Chinese older participants' individual modernity modes. It is further suggested that governments at all levels should allow for options and opportunities for older people to align themselves in the modernisation process by removing the barriers that may hinder their integration and empowerment efforts. While it is important to respect older adults' different responses in the face of modernisation, their participation in societies should be encouraged and respected by the wider society in the context of modernisation.
Swimming upstream: the provision of inclusive care to older lesbian, gay and bisexual (LGB) adults in residential and nursing environments in Wales
Authors: WILLIS PAUL , MAEGUSUKU-HEWETT TRACEY , RAITHBY MICHELE , MILES PENNY
Published: October 2014

This paper examines the ways in which older people's residential and nursing homes can constitute heteronormative environments – social spaces in which the same-sex attractions and desires of residents are disregarded in the provision of everyday care. The aim of this discussion is to examine the synergies and differences between older lesbian, gay and bisexual (LGB) adults' expectations for future care home provision and the expectations of care staff and managers in providing residential services to older people with diverse sexual backgrounds. We present qualitative evidence from research into the provision of care environments in Wales. In this paper, we present findings from two cohorts: first, from five focus groups with care and nursing staff and managers; and second, from 29 semi-structured interviews with older LGB adults (50–76 years) residing in urban and rural locations across Wales. We argue that residential care environments can constitute heterosexualised spaces in which LGB identities are neglected in comparison to the needs and preferences of other residents. To this extent, we discuss how care staff and managers can be more attentive and responsive to the sexual biographies of all residents and argue against the separation of care and sexual orientation in practice.
ESTIMATION AND INFERENCE FOR VARYING-COEFFICIENT MODELS WITH NONSTATIONARY REGRESSORS USING PENALIZED SPLINES
Authors: Chen Haiqiang , Fang Ying , Li Yingxing
Published: October 2014

This paper considers estimation and inference for varying-coefficient models with nonstationary regressors. We propose a nonparametric estimation method using penalized splines, which achieves the same optimal convergence rate as kernel-based methods, but enjoys computation advantages. Utilizing the mixed model representation of penalized splines, we develop a likelihood ratio test statistic for checking the stability of the regression coefficients. We derive both the exact and the asymptotic null distributions of this test statistic. We also demonstrate its optimality by examining its local power performance. These theoretical findings are well supported by simulation studies.