bluuebunny/crossref_metadata_2025 huggingface dataset:
Warfarin in Atrial Fibrillation Patients with Moderate Chronic Kidney Disease
Authors: Hart Robert G. , Pearce Lesly A. , Asinger Richard W. , Herzog Charles A.
Published: September 2011

Background and objectives

The efficacy of adjusted-dose warfarin for prevention of stroke in atrial fibrillation patients with stage 3 chronic kidney disease (CKD) is unknown.

Design, setting, participants, & measurements

Patients with stage 3 CKD participating in the Stroke Prevention in Atrial Fibrillation 3 trials were assessed to determine the effect of warfarin anticoagulation on stroke and major hemorrhage, and whether CKD status independently contributed to stroke risk. High-risk participants (n = 1044) in the randomized trial were assigned to adjusted-dose warfarin (target international normalized ratio 2 to 3) versus aspirin (325 mg) plus fixed, low-dose warfarin (subsequently shown to be equivalent to aspirin alone). Low-risk participants (n = 892) all received 325 mg aspirin daily. The primary outcome was ischemic stroke (96%) or systemic embolism (4%).

Results

Among the 1936 participants in the two trials, 42% (n = 805) had stage 3 CKD at entry. Considering the 1314 patients not assigned to adjusted-dose warfarin, the primary event rate was double among those with stage 3 CKD (hazard ratio 2.0, 95% CI 1.2, 3.3) versus those with a higher estimated GFR (eGFR). Among the 516 participants with stage 3 CKD included in the randomized trial, ischemic stroke/systemic embolism was reduced 76% (95% CI 42, 90; P < 0.001) by adjusted-dose warfarin compared with aspirin/low-dose warfarin; there was no difference in major hemorrhage (5 patients versus 6 patients, respectively).

Conclusions

Among atrial fibrillation patients participating in the Stroke Prevention in Atrial Fibrillation III trials, stage 3 CKD was associated with higher rates of ischemic stroke/systemic embolism. Adjusted-dose warfarin markedly reduced ischemic stroke/systemic embolism in high-risk atrial fibrillation patients with stage 3 CKD.
Interaction of Time-Varying Albumin and Phosphorus on Mortality in Incident Dialysis Patients
Authors: Zitt Emanuel , Lamina Claudia , Sturm Gisela , Knoll Florian , Lins Friederike , Freistätter Otto , Kronenberg Florian , Lhotta Karl , Neyer Ulrich
Published: September 2011

Background and objectives

Hypoalbuminemia and hyperphosphatemia have been shown to be strong predictors of mortality in dialysis patients that might not be independent from each other. We prospectively investigated the relationship and interaction between serum albumin and phosphorus with all-cause mortality in an inception cohort of incident dialysis patients.

Design, setting, participants, & measurements

We followed 235 incident dialysis patients in a prospective single-center cohort study (INVOR study) applying a time-dependent Cox proportional hazards model using all measured laboratory values (2887 albumin and 10306 phosphorus values).

Results

Eighty-two patients (35%) died during a median follow-up of 35.1 months. Albumin was inversely associated with mortality (hazard ratio [95% confidence interval]: 0.23 [0.14 to 0.36]; P < 0.001), whereas higher phosphorus concentrations showed a trend to an increasing risk for mortality (hazard ratio 1.57 [95% confidence interval 0.97 to 2.54]; P = 0.07). Importantly, we observed a significant interaction between albumin and phosphorus (P = 0.01). The lowest risk was found with concurrent low phosphorus and high albumin values, whereas risk was increased with either concurrent low phosphorus and low albumin values or high phosphorus and high albumin values.

Conclusions

In incident dialysis patients the associations of serum phosphorus and albumin concentrations with mortality are modified by each other over time. Phosphorus-lowering interventions that concomitantly can cause a fall in serum albumin level may be harmful and warrant additional studies. If confirmed, epidemiologic studies and therapeutic guidelines aiming for target values should consider this interplay.
Cultural Dimensions and Leadership Styles Perceived by Future Managers: Differences between Slovenia and a Cluster of Central European Countries
Authors: Pučko Danijel , Čater Tomaž
Published: September 2011

Cultural Dimensions and Leadership Styles Perceived by Future Managers: Differences between Slovenia and a Cluster of Central European Countries

The article contributes to the body of knowledge about the perceptions of future managers (i.e. business and engineering students) in both Slovenia and a cluster of Central European (CE) countries regarding actual cultural practices in their social environments, the value systems they possess and their attitudes to leadership styles. The main question addressed is whether future Slovenian managers are good representatives of the average future manager from CE (transitional) countries as far as their value system and attitudes to individual leadership styles are concerned.

The research results confirm that the Slovenian (potential) future managers perceive actual cultural practices in their environment rather differently from their counterparts from the cluster of CE countries. Two decades of transition from socialist/communist socio-economic systems were apparently not long enough periods to achieve a higher level of harmonisation of existing cultures. The relevant value systems held by the Slovenian (potential) future managers and the CE cluster's future managers still differ significantly. The Slovenian future managers have (statistically) significantly different attitudes to individual leadership styles than their counterparts in the CE countries' cluster. The smallest differences in perceptions between the two stated groups of (potential) future managers exist regarding their views on what are the most important traits and skills of managers.
An Example of Two-Dimensional Interpolation Using a Linear Combination of Bicubic B-Splines
Authors: Rosłoniec Stanisław
Published: September 2011

An Example of Two-Dimensional Interpolation Using a Linear Combination of Bicubic B-Splines

The paper describes how a linear combination of bicubic B-splines can be effectively used in a two-dimensional interpolation. It is assumed that values of a function to be interpolated are evaluated at the uniformly located nodes of a corresponding rectangular grid. All formulae of importance have been derived step by step and are presented in a form convenient for computer implementations. To ensure clarity of considerations a short description of one-dimensional B-spline is also given in Appendix 1. The usefulness of the presented interpolation algorithm has been confirmed by the real engineering example of applications.
Experimental Investigation of Factors Affecting Stability of Interferometric Measurements with Ground Based Noise Waveform SAR
Authors: Lukin Konstantin , Palamarchuk Volodymyr , Vyplavin Pavlo , Kudriashov Volodymyr
Published: September 2011

Experimental Investigation of Factors Affecting Stability of Interferometric Measurements with Ground Based Noise Waveform SAR

Application of ground-based SAR and differential interferometry technique is often used for monitoring manmade objects aiming detection of their structural changes. Recently Ka-band Ground Based Noise Waveform SAR has been developed [1] which may be applied for the above monitoring. The paper is devoted to investigation of stability of Noise Waveform SAR. Monitoring of a simple construction has been carried out. The related measurements enabled estimating the accuracy of differential phase measurements using the above Ka-band Noise Waveform SAR. In the paper we present some results of the experiments and their explanations.
Analysis of ascending spinal tract degeneration in cervical spondylotic myelopathy using 3D anisotropy contrast single-shot echo planar imaging on a 3.0-T system
Authors: Urakawa Takaaki , Matsuzawa Hitoshi , Suzuki Yuji , Endo Naoto , Kwee Ingrid L. , Nakada Tsutomu
Published: September 2011

Object

The authors assessed the role of 3D anisotropy contrast (3DAC) in evaluating specific ascending tract degeneration in patients with cervical spondylotic myelopathy (CSM).

Methods

The authors studied 10 patients (2 women, 8 men; mean age 59.8 ± 14.6 years) with CSM and spinal cord compression below the C2–3 disc level, as well as 10 healthy control individuals (3 women, 7 men; mean age 42.0 ± 24.1 years). Images of the cervical cord at the C2–3 level were obtained using a 3.0-T MR imaging system.

Results

Three-dimensional anisotropy contrast imaging clearly made possible tract-by-tract analysis of the fasciculus cuneatus, fasciculus gracilis, and spinocerebellar tract. Tract degeneration identified using 3DAC showed good correlation with a decline in fractional anisotropy. Degeneration of the fasciculus gracilis detected by “vector contrast” demonstrated a good correlation with Nurick grades.

Conclusions

The study unambiguously demonstrated that 3DAC imaging is capable of assessing ascending tract degeneration in patients with CSM. Degeneration of an individual tract can be easily identified as a vector contrast change on the 3DAC image, a reflection of quantitative changes in anisotropism, similar to fractional anisotropy. Excellent correlation between Nurick grades and fasciculus gracilis degeneration suggests potential application of 3DAC imaging for tract-by-tract clinical correlation.
Communicating hydrocephalus following surgery and adjuvant radiochemotherapy for glioblastoma
Authors: Montano Nicola , D'Alessandris Quintino Giorgio , Bianchi Federico , Lauretti Liverana , Doglietto Francesco , Fernandez Eduardo , Maira Giulio , Pallini Roberto
Published: September 2011

Object

Communicating hydrocephalus is an uncommon complication in patients treated for glioblastoma multiforme (GBM). Its pathogenesis remains unclear. The authors evaluated the clinical and radiological factors associated with the onset of communicating hydrocephalus and the impact of ventriculoperitoneal (VP) shunt surgery on the outcome of these patients.

Methods

One hundred twenty-four patients harboring GBM, who had undergone craniotomy for tumor resection and adjuvant radiochemotherapy, were retrospectively assessed. Seven of them developed communicating hydrocephalus and were treated with VP shunt surgery. Clinical and radiological estimates included Karnofsky Performance Scale (KPS) score, previous surgery, overall survival (OS), CSF pressure and components, tumor location, and leptomeningeal dissemination.

Results

All 7 patients who developed communicating hydrocephalus had undergone at least 2 craniotomies for tumor resection before the onset of hydrocephalus (p = 0.0006; Fisher exact test). Six cases showed high levels of CSF proteins. There was a highly significant relationship between ventricular opening at surgery for tumor recurrence and onset of hydrocephalus (p = 0.0002; Fisher exact test). In these patients, VP shunt surgery was followed by a significant improvement of KPS score (p = 0.0180; Wilcoxon signed-rank test). The median OS after VP shunt insertion was 5 ± 2.9 months.

Conclusions

Ventricular opening after radiochemotherapy and high CSF protein levels are significant predictors of communicating hydrocephalus in patients with GBM. The VP shunt surgery improves quality of life in these patients.
Spatial distribution of surface ablation in the terminus of Rhonegletscher, Switzerland
Authors: Sugiyama Shin , Yoshizawa Takeshi , Huss Matthias , Tsutaki Shun , Nishimura Daisuke
Published: September 2011

Abstarct

The spatial pattern of glacier surface melt was measured with a resolution of 20–100m within a region extending 1 km up-glacier from the terminus of Rhonegletscher, Switzerland. The melt rate was monitored from 6 July to 6 September 2009 using 44 ablation stakes. We also measured the surface albedo near the stakes to investigate the importance of this parameter for the melt-rate distribution. The melt rate varied from 32.8 to 71.9 mm w.e. d–1in the study area. Our measurements suggest that the spatial variation of the melt rate can be explained by (1) shading of the ice surface by neighbouring mountains, (2) surface albedo and (3) effects of microclimate (e.g. radiation from sidewalls) on the surface energy balance. The observed melt-rate distribution was compared to the results of a temperature-index melt model, which takes into account shading of direct solar illumination but not the other two effects. The model reproduces some important features of the field data, but its spatial variations are generally less than the measured values. Our study shows the importance of albedo and other local conditions in the accurate estimation of the small-scale melt-rate distribution.
Enforcing Performance: Disciplining Girls in British Co-educational Boarding School Stories, 1928–58
Authors: HOLLOWELL CLARE
Published: September 2011

This paper examines girls and power in British co-educational boarding school stories published from 1928 to 1958. While feminist scholars have hailed the girls’ school story as a site of potential resistance to constricting gender roles, the same can not be said of the co-educational school story. While the genres share many tropes and characterisation, the move from an all-female world to a co-educational setting allows the characters access to a narrower range of gender roles, and renders the female characters significantly less powerful. The disciplinary structures of the co-educational schools, mirroring those in real life, operate in a supposedly progressive manner that in fact removes girls from access to power.
Power of Darkness: Narrative and Biographical Reflexivity in A Series of Unfortunate Events
Authors: BULLEN ELIZABETH
Published: September 2011

This paper investigates the high-earning children's series, A Series of Unfortunate Events, in relation to the skills young people require to survive and thrive in what Ulrich Beck calls risk society. Children's textual culture has been traditionally informed by assumptions about childhood happiness and the need to reassure young readers that the world is safe. The genre is consequently vexed by adult anxiety about children's exposure to certain kinds of knowledge. This paper discusses the implications of the representation of adversity in the Lemony Snicket series via its subversions of the conventions of children's fiction and metafictional strategies. Its central claim is that the self-consciousness or self-reflexivity of A Series of Unfortunate Events} models one of the forms of reflexivity children need to be resilient in the face of adversity and to empower them to undertake the biographical project risk society requires of them.
Vaccines against a Major Cause of Abortion in Cattle, Neospora caninum Infection
Authors: Monney Thierry , Debache Karim , Hemphill Andrew
Published: September 2011

Neosporosis, caused by the apicomplexan parasite Neospora caninum, represents one of the economically most important causes of abortion in cattle. During pregnancy, the parasite infects the placental tissue and the fetus, which can lead to stillbirth, abortion, or birth of weak calves. Alternatively, calves are born without clinical symptoms, but they can carry over the parasite to the next generation. In addition, N. caninum causes neuromuscular disease in dogs. The economic importance of neosporosis has prompted researchers to invest in the development of measures to prevent infection of cattle by vaccination. A good vaccine must stimulate protective cellular immune responses as well as antibody responses at mucosal sites and, systemically, must activate T-helper cells to produce relevant cytokines, and must elicit specific antibodies that aid in limiting parasite proliferation, e.g., by interference with host cell invasion, activation of complement, and/or opsonization of parasites to have them killed by macrophages. Different types of vaccines have been investigated, either in bovines or in the mouse model. These include live vaccines such as naturally less virulent isolates of N. caninum, attenuated strains generated by irradiation or chemical means, or genetically modified transgenic strains. Live vaccines were shown to be very effective; however, there are serious disadvantages in terms of safety, costs of production, and stability of the final product. Subunit vaccines have been intensively studied, as they would have clear advantages such as reduced costs in production, processing and storage, increased stability and shelf life. The parasite antigens involved in adhesion and invasion of host cells, such as surface constituents, microneme-, rhoptry- and dense granule-components represent interesting targets. Subunit vaccines have been applied as bacterially expressed recombinant antigens or as DNA vaccines. Besides monovalent vaccines also polyvalent combinations of different antigens have been used, providing increased protection. Vaccines have been combined with immunostimulating carriers and, more recently, chimeric vaccines, incorporating immuno-relevant domains of several antigens into a single protein, have been developed.
Crystal Structure and Density Functional Theory Study on Structural Properties and Energies of a Isonicotinohydrazide Compound
Authors: Sahebalzamani Hajar , Khaligh Nina , Ghammamy Shahriar , Salimi Farshid , Mehrani Kheyrollah
Published: September 2011

An X-ray and a theoretical study of the structure of the isoniazid derivative N'-(4-dimethylaminobenzylidene)-isonicotinohydrazide monohydrate (1) are reported. In this work, we will report a combined experimental and theoretical study on the molecular structure, vibrational spectra and energies of N'-(4-dimethylaminobenzylidene)-isonicotinohydrazide monohydrate. The calculated parameters are in good agreement with the corresponding X-ray diffraction values. The FTIR spectrum in the range of 400–4000 cm−1 of N'-(4-dimethylaminobenzylidene)-isonicotinohydrazide monohydrate has been recorded. The molecular geometry and vibrational frequencies and energies in the ground state are calculated by using the DFT (B3LYP, PBE1PBE) methods with 6-311G** basis sets. The calculated HOMO and LUMO energies also confirm that charge transfer occurs within the molecule. The geometries and normal modes of vibrations obtained from B3LYP/PBE1PBE/6-311G** calculations are in good agreement with the experimentally observed data.
Chemical Composition and Possible in Vitro Phytotoxic Activity of Helichrsyum italicum (Roth) Don ssp. italicum
Authors: Mancini Emilia , De Martino Laura , Marandino Aurelio , Scognamiglio Maria Rosa , De Feo Vincenzo
Published: September 2011

The chemical composition of the essential oil of Helichrysum italicum (Roth) Don ssp. italicum, collected in the National Park of Cilento and Diano Valley, Southern Italy, was studied by means of GC and GC/MS. Forty four compounds of 45 constituents were identified in the oil, mainly oxygenated sesquiterpenes. The essential oil was evaluated for its potential in vitro phytotoxic activity against germination and early radicle elongation of radish and garden cress. The radicle elongation of radish was significantly inhibited at the highest doses tested, while germination of both seeds was not affected.
Aggregatibacter actinomycetemcomitans Leukotoxin: A Powerful Tool with Capacity to Cause Imbalance in the Host Inflammatory Response
Authors: Johansson Anders
Published: September 2011

Aggregatibacter actinomycetemcomitans has been described as a member of the indigenous oral microbiota of humans, and is involved in the pathology of periodontitis and various non-oral infections. This bacterium selectively kills human leukocytes through expression of leukotoxin, a large pore-forming protein that belongs to the Repeat in Toxin (RTX) family. The specificity of the toxin is related to its prerequisite for a specific target cell receptor, LFA-1, which is solely expressed on leukocytes. The leukotoxin causes death of different leukocyte populations in a variety of ways. It activates a rapid release of lysosomal enzymes and MMPs from neutrophils and causes apoptosis in lymphocytes. In the monocytes/macrophages, the toxin activates caspase-1, a cysteine proteinase, which causes a proinflammatory response by the activation and secretion of IL-1β and IL-18. A specific clone (JP2) of A. actinomycetemcomitans with enhanced leukotoxin expression significantly correlates to disease onset in infected individuals. Taken together, the mechanisms by which this toxin kills leukocytes are closely related to the pathogenic mechanisms of inflammatory disorders, such as periodontitis. Therapeutic strategies targeting the cellular and molecular inflammatory host response in periodontal diseases might be a future treatment alternative.
Inhibition of Influenza Virus Replication by Constrained Peptides Targeting Nucleoprotein
Authors: Jiang Hongbing , Xu Yidong , Li Li , Weng Leiyun , Wang Qiang , Zhang Shijian , Jia Baosen , Hu Hongxing , He Ying , Jacob Yves , Toyoda Tetsuya
Published: September 2011

Background:

Because of high mutation rates, new drug-resistant viruses are rapidly evolving, thus making the necessary control of influenza virus infection difficult. Methods: We screened a constrained cysteine-rich peptide library mimicking μ-conotoxins from Conus geographus and a proline-rich peptide library mimicking lebocin 1 and 2 from Bombyx mori by using influenza virus RNA polymerase (PB1, PB2 and PA) and nucleoprotein (NP) as baits.

Results:

Among the 22 peptides selected from the libraries, we found that the NP-binding proline-rich peptide, PPWCCCSPMKRASPPPAQSDLPATPKCPP, inhibited influenza replicon activity to mean ±SD 40.7% ±15.8% when expressed as a GFP fusion peptide in replicon cells. Moreover, when the GFP fusion peptide was transduced into cells by an HIV-TAT protein transduction domain sequence, the replication of influenza virus A/WSN/33 (WSN) at a multiplicity of infection of 0.01 was inhibited to 20% and 69% at 12 and 24 h post-infection, respectively. In addition, the TAT-GFP fusion peptide was able to slightly protect Balb/c mice from WSN infection when administrated prior to the infection. Conclusions: These results suggest the potential of this peptide as the seed of an anti-influenza drug and reveal the usefulness of the constrained peptide strategy for generating inhibitors of influenza infection. The results also suggest that influenza NP, which is conserved among the influenza A viruses, is a good target for influenza inhibition, despite being the most abundant protein in infected cells.
Contribution à une approche sociologique de la genèse partisane
Authors: Aït-Aoudia Myriam , Dézé Alexandre
Published: September 2011

Résumé Cet article ambitionne de proposer une analyse sociologique de la genèse partisane à partir de l’étude du FN, du MSI et du FIS et, partant, de tenter de dépasser les écueils des approches classiques qui traitent rarement de ce phénomène en lui-même et pour lui-même. En mettant entre parenthèses l’issue du processus de création partisane pour mieux en restituer toute l’incertitude et la complexité, nous nous intéressons tout d’abord aux acteurs de la fabrique partisane, à leurs interactions préalables dans les milieux « pré-partisans » et à leurs luttes pour la définition du mode d’action légitime. Nous analysons ensuite le travail de mise en forme proprement dit des partis – travail dont nous démontrons qu’il repose pour l’essentiel sur une entreprise de conformation.
An Analysis of the Hip and Knee Reconstruction Section of the Orthopaedic In-Training Examination
Authors: Cross Michael B. , Osbahr Daryl C. , Nam Denis , Reinhardt Keith R. , Bostrom Mathias P.G. , Dines Joshua S.
Published: September 2011

This article analyzes the hip and knee reconstruction section of the Orthopaedic In-Training Examination (OITE). All of the hip and knee reconstruction questions from 2005 to 2009 were analyzed, and the following data were recorded: number of questions per year in the hip and knee section, total number of questions on the OITE per year, national average score by year in training, references cited, taxonomy classification of each question, topics that were tested, imaging modalities used for a given question, and treatment modalities tested. Eight percent to 9% of the questions on the OITE each year were hip and knee reconstruction-related questions. Performance improved with each year in training, but not by a statistically significant amount. The most commonly tested topics over the past 5 years were anatomy and physiology, ligament and/or gap balancing during total knee arthroplasty (TKA), surgical approaches, properties of polyethylene, periprosthetic fractures about an arthroplasty, and questions dealing with the mechanical properties of implants. In 4 out of 5 years, the majority of questions were classified as Taxonomy 1 (knowledge and recall). The bulk of the questions each year did not require the examinee to interpret a radiograph or make a treatment decision. The most common references cited were from
Journal of Bone and Joint Surgery (American)
, followed by the
Journal of Arthroplasty
. This detailed analysis of the hip and knee reconstruction section of the OITE should improve resident performance, and may serve as a study tool for the OITE.
Cemented Femoral Fixation: The North Atlantic Divide
Authors: Murray David W.
Published: September 2011

In the United Kingdom, more cemented than cementless stems are implanted, whereas in North America, few cemented stems are implanted. This is primarily because cemented stems have not performed well in North America, whereas they have in the United Kingdom, as different designs have been used.

The majority of cemented stems used in the United Kingdom are polished, collarless, and tapered. These are forgiving, as they subside within the cement mantle and compress the cement and stabilize the interface. They perform well in both young and active patients and elderly patients. They also do well in osteoporotic bone, with deformity, or with suboptimal cementing techniques. As the position of the stem can be varied, it is simple to achieve appropriate leg length, offset, and version. Cement can be used to deliver antibiotics locally. If revision is necessary, it is relatively straightforward. Cement has numerous advantages that outweigh the main disadvantage of an extended operating time.
Minimizing Infection Risk: Fortune Favors the Prepared Mind
Authors: Dunbar Michael J. , Richardson Glen
Published: September 2011

Despite advances in care, infection in total joint arthroplasty remains a serious problem that has yet to be solved. Reported infection rates range from <0.5% in highly specialized centers to a high of 2% as reported at a national level. The epidemiology of total joint arthroplasty remains challenging because of the relatively low, but significant, incidence of infection. Still, there are variables that can be addressed that have demonstrated evidence regarding reduction in infection rates. These variables include optimizing medical conditions in the preoperative period such as anemia, blood glucose, and nutrition. In the perioperative period, administration of parenteral antibiotics within 1 hour of incision is a must. The effect of the operating room environment is less clear, but it is evident that traffic flow in the operating room has a negative effect on infection rates. Skin preparation with chlohexidine is now the agent of choice, and evidence exists that iodophor impregnated occlusive dressings add value. Razors should not be used. Surgical staples for closure have an increased risk of superficial infection as compared to subcuticular sutures. In the postoperative period, early, persistent wound drainage should be managed aggressively. There is no evidence to support the use of parenteral antibiotics past 24 hours in routine cases. Patients should be advised about prophylaxis for infection when undergoing dental work and other high-risk procedures. There is a strong movement to extend this prophylactic period indefinitely, as opposed to 2 years postoperatively. Finally, and perhaps most importantly, it is the surgeon’s responsibility to be aware of all these issues and to strongly advocate for patient safety in ensuring that infection risk is minimized.
Treating Abductor Deficiency: A Transference Technique
Authors: Whiteside Leo A.
Published: September 2011

Loss of abduction power is a common problem after total hip arthroplasty (THA) and may lead to severe limp and instability. A surgical reconstruction technique using a gluteus maximus flap transfer was developed to repair deficient abductor muscles and capsule. The gluteus maximus muscle was split as in a posterior approach to the hip, and the anterior portion of the muscle was elevated as a flap, separating it from the fascia lata and fashioning a triangular distal fascial end. The lateral surface of the greater trochanter was decorticated, and the anterior half of the gluteus maximus was sutured to the greater trochanter with multiple nonabsorbable sutures through drill holes in the bone. The distal fascial end was sutured beneath the vastus lateralis muscle with heavy absorbable sutures. The posterior portion of the gluteus maximus (approximately one-sixth of the muscle body and half the length) was passed beneath the primary flap to substitute for the gluteus minimus and capsule. The tensioning of the flap was done with the hip in 15° to 20° abduction to ensure adequate tension in the transferred muscle. The lower half of the gluteus maximus muscle and fascia lata were also closed over the greater trochanter and transferred muscle flap with the hip abducted and then closed proximally, leaving the anterior edge of the gluteus maximus flap unsutured so that the transferred muscle would be allowed to pull directly on the greater trochanter. Gradual rehabilitation included 2-handed support for 8 weeks and careful gradual abduction exercises beginning 4 weeks postoperatively.
Distal Femoral Varus Osteotomy: Unloading the Lateral Compartment: Long-term Follow-up of 45 Medial Closing Wedge Osteotomies
Authors: Sternheim Amir , Garbedian Shawn , Backstein David
Published: September 2011

Distal femoral medial closing wedge osteotomy is useful for mechanical axis realignment to unload the lateral compartment of the valgus knee. The primary indication for unloading the lateral compartment is lateral unicompartmental osteoarthritis. Alternative treatment options include lateral unicompartment or total knee arthroplasty (TKA). Prerequisites for the osteotomy include a 90° arc of motion, age younger than 60 years, and an active patient capable of an extensive period of rehabilitation. Surgery is carried out through a midline skin incision and uses a subvastus approach. The medial femoral closing wedge osteotomy is fixed with a 90° dynamic compression blade plate. A critical technical point is the need to insert the blade plate parallel to the joint line. The right angle plate corrects the tibialfemoral angle to 0°. A benefit of the closing wedge over an opening wedge osteotomy is reduced risk of nonunion. Survivorship and functional outcome of 41 patients with 45 distal femoral varus osteotomies at a mean follow-up of 13.3 years were retrospectively analyzed. Survivorship at 10, 15, and 20 years was 90%, 79%, and 21.5% respectively. Mean Modified Knee Society Score was 36.1 preoperatively, 74.4 at 1-year postoperatively, and 60.5 at last follow-up. Distal femoral varus osteotomy is effective at unloading the lateral compartment in unicompartmental arthritis in the valgus knee. It may be indicated in the young, high activity demand, and overweight patient. By 20 years after the osteotomy most patients require conversion to TKA.
Wound Healing Problems in Total Knee Arthroplasty
Authors: Garbedian Shawn , Sternheim Amir , Backstein David
Published: September 2011

It is important to avoid underestimating the significance of wound complications following total knee arthroplasty (TKA). Expedient and aggressive care is recommended. Understanding the blood supply to the skin around the knee and measures to prevent wound complications are fundamental to preventing wound problems. A detailed patient history and physical examination will identify high-risk patients and any modifiable risk factors. Operative techniques such as raising full-thickness skin flaps and judicious placement of skin incisions in the presence of pre-existing scars can greatly reduce the incidence of wound problems. The first step in treating wound problems is recognizing when a problem is present and knowing when a minor problem can turn into a major one. Superficial infections or stitch abscesses can be treated with conservative treatment. However, the surgeon should have a low threshold to revert to surgical management if drainage persists. Skin necrosis or non-viable skin must be excised in the operating room, and the presence of a deep infection must be diagnosed by joint aspiration. The appropriate course of action in dealing with deep infection is dependent on the duration elapsed since the index procedure. The ability to perform a medial gastrocnemius muscle flap and skin graft is an invaluable skill in complex cases where primary wound closure cannot be achieved. Meticulous attention to detail during surgery and aggressive surgical treatment of wound complications can be the difference in saving the knee.
The Results of TKA: What the Registries Don’t Tell Us
Authors: Barrack Robert L.
Published: September 2011

National registries have provided valuable feedback to surgeons and improved patient care by decreasing revision rates and identifying defective or poorly performing devices. Although there have been thousands of peer review publications in the literature, significant gaps exist in relevant knowledge relating to performance of hip and knee devices due to shortcomings in many published studies. Most studies come from specialty centers and may not reflect the results that can be expected from devices in widespread use. Sample sizes are frequently small, and studies are underpowered to draw major conclusions or to stratify data based on clinically important variables. National registries effectively address many of these problems, but also have shortcomings. Registry data are now being used to promote specific devices, which opens the door to potential abuse of this information. While device design can impact implant survival, other factors, such as surgical technique, surgeon, hospital, patient factors, and even country, may have far more impact on revision rate than implant design. Revision rates often differ among different designs by as little as 5% to 10% while these previously mentioned factors can result in differences in revision rate and order of magnitude higher. Failure to control these numerous other potentially confounding variables can lead to false or misleading conclusions. In general, registries are far more effective in identifying poorly performing devices that manifest in clusters of failures than in identifying small differences in performance among relatively well-designed devices. It is important for surgeons interpreting data generated from registries to be aware of potential pitfalls of these data as well as their value.
TKA Sans Tourniquet: Let It Bleed: Opposes
Authors: Whitehead David J. , MacDonald Steven J.
Published: September 2011

The literature supports the routine use of a tourniquet during total knee arthroplasty (TKA). With tourniquet use, there is decreased intraoperative blood loss with subsequent improved visibility and a bloodless surgical field. This facilitates efficiency with the potential for decreased operating time. Increased operating time has been associated with an increase in the incidence of infection after TKA.

Opponents of routine tourniquet use cite rare or theoretical concerns. Multiple authors have concluded that the incidence of deep vein thrombosis is not related to using a tourniquet. The rare events of muscle dysfunction or nerve injury are transient. Peripheral vascular disease, in which patients have no palpable distal pulses, should be considered a possible contraindication to the use of a tourniquet during TKA. If tourniquet time and pressure are respected during TKA, we believe the benefits outweigh the perceived and theoretical concerns.
Why Knees Fail in 2011: Patient, Surgeon, or Device?
Authors: Fitzgerald Steven J. , Trousdale Robert T.
Published: September 2011

The outcome of total knee arthroplasty (TKA) is influenced by multiple interconnected factors, including patient selection, implant design, and surgical technique. Total knee arthroplasty has been shown to be highly successful, with patient satisfaction rates reported from 85% to 95% with low rates of failure, but if failure occurs, its impact is significant. In 2003, 402,000 primary TKAs and 32,000 revision TKAs were performed in the United States, and the number of TKAs is expected to double by 2015. Recent data on modern implant designs and techniques have demonstrated a surprising number of early failures, although the true number of early failures is unknown. Patient medical comorbidities should be optimized preoperatively, while psychosocial issues and workers compensation are more nebulous yet contribute greatly to patient perceived outcomes. Understanding current failure mechanisms of primary TKA and how to prevent complications will be critical to help manage a potentially overwhelming TKA revision burden. This article discusses failure rates as well as factors from the patient, surgeon, and device, that contribute to TKA failure.
Instability in Primary Total Knee Arthroplasty
Authors: Del gaizo Daniel J. , Della Valle Craig J.
Published: September 2011

Instability is one of the most common causes of failure of total knee arthroplasty (TKA). The presentation can vary from pain to frank dislocation with the etiologies just as varied. Instability after TKA can be classified by where the instability occurs in the knee’s arc of motion as well as the chronicity of the problem. Acute instability is related to intraoperative injuries or excessive release of important coronal stabilizers such as the medial collateral ligament in extension or the posterolateral corner in flexion. Chronic instability in extension is often related to varus/valgus malalignment. Chronic instability in flexion can be related to an undersized femoral component, excessive tibial slope, or excessive elevation of the joint line affecting the isometry of the collateral ligaments in midflexion. Recurvatum instability is a rare complication that often coincides with extensor mechanism dysfunction or neuromuscular disorders. When addressing instability after TKA, it is critical to determine the root cause of the problem as well as evaluate for other causes of pain such as infection or aseptic loosening. When revision surgery is warranted, it should follow the basic principles of restoring a neutral mechanical alignment, setting the appropriate component rotation, balancing the flexion and extension spaces, and restoring the height of the native joint line.
Multiple Needle Puncturing: Balancing the Varus Knee
Authors: Bellemans Johan
Published: September 2011

The so-called “pie crusting” technique using multiple stab incisions is a well-established procedure for correcting tightness of the iliotibial band in the valgus knee. It is, however, not applicable for balancing the medial side in varus knees because of the risk for iatrogenic transsection of the medial collateral ligament (MCL). This article presents our experience with a safer alternative and minimally invasive technique for medial soft tissue balancing, where we make multiple punctures in the MCL using a 19-gauge needle to progressively stretch the MCL until a correct ligament balance is achieved. Our technique requires minimal to no additional soft tissue dissection and can even be performed percutaneously when necessary. This technique, therefore, does not impact the length of the skin or soft tissue incisions. We analyzed 61 cases with varus deformity that were intraoperatively treated using this technique. In 4 other cases, the technique was used as a percutaneous procedure to correct postoperative medial tightness that caused persistent pain on the medial side. The procedure was considered successful when a 2- to 4-mm mediolateral joint line opening was obtained in extension and 2 to 6 mm in flexion. In 62 cases (95%), a progressive correction of medial tightness was achieved according to the above-described criteria. Three cases were overreleased and required compensatory release of the lateral structures and use of a thicker insert. Based on these results, we consider needle puncturing an effective and safe technique for progressive correction of MCL tightness during minimally invasive total knee arthroplasty.
Teriparatide (rh [1–34] PTH) Improved Osteointegration of a Hemiarthroplasty With Signs of Aseptic Loosening
Authors: Oteo-Álvaro Ángel , Matas José A. , Alonso-Farto Juan C.
Published: September 2011

Incidences of osteoporosis and fragility fractures are constantly increasing, which are associated with increased morbidity and mortality. When these patients undergo surgery, a higher number of postoperative complications may be expected because of poor bone quality and delayed healing. As a result, poorer primary stability of the implant, initial loosening, and impaired fixation strength in different regions may be seen. In these patients, we can choose the most advanced implants, but it is necessary to stimulate bone biology to increase the stability of the implant. This article reports the result obtained in a patient diagnosed with osteoporosis with aseptic loosening of a hip hemiarthroplasty after treatment with teriparatide (rh [1–34] PTH). This drug is indicated for the treatment of osteoporosis in men and postmenopausal women with high fracture risk and glucocorticoid-induced osteoporosis, and is administered subcutaneously for 2 years. It has an anabolic effect through stimulation of the osteoblast population that increases trabecular connectivity, cortical thickness, and bone mineral content. In animal models, teriparatide improved implant fixation 2 to 4 weeks after administration, resulting in the thickening of bone trabeculae and increased bone mass in the peri-implant area. In this retrospective analysis of clinical data and radiographic and scintigraphic images, after 24 months of treatment, the patient experienced clinical improvement associated with the disappearance of radiographic signs of loosening and a decrease in pathological radiotracer uptake in the bone scan, which are signs of osteointegration after treatment with teriparatide.
Pulse-Encoded Ultrasound Imaging of the Vitreous With an Annular Array
Authors: Silverman Ronald H. , Ketterling Jeffrey A. , Mamou Jonathan , Lloyd Harriet O. , Filoux Erwan , Coleman D. Jackson
Published: September 2011

The vitreous body is nearly transparent both optically and ultrasonically. Conventional 10- to 12-MHz diagnostic ultrasound can detect vitreous inhomogeneities at high gain settings, but has limited resolution and sensitivity, especially outside the fixed focal zone near the retina. To improve visualization of faint intravitreal fluid/gel interfaces, the authors fabricated a spherically curved 20-MHz five-element annular array ultrasound transducer, implemented a synthetic-focusing algorithm to extend the depth-of-field, and used a pulse-encoding strategy to increase sensitivity. The authors evaluated a human subject with a recent posterior vitreous detachment and compared the annular array with conventional 10-MHz ultrasound and spectral-domain optical coherence tomography. With synthetic focusing and chirp pulse-encoding, the array allowed visualization of the formed and fluid components of the vitreous with improved sensitivity and resolution compared with the conventional B-scan. Although optical coherence tomography allowed assessment of the posterior vitreoretinal interface, the ultrasound array allowed evaluation of the entire vitreous body.
Estudio de los mecanismos de activación de la esfalerita con Cu(II) y Pb(II)
Authors: Dávila Pulido G. I. , Uribe Salas A.
Published: September 2011

Este artículo presenta los resultados de un estudio experimental sobre la activación de esfalerita (ZnS) con Cu(II) y Pb(II), cuyo objetivo principal consistió en investigar los mecanismos de activación y en evaluar la magnitud relativa de la hidrofobización alcanzada con ambas especies químicas. La hidrofobicidad que la superficie mineral adquiere como resultado de la interacción con los activadores y colectores tipo xantato (ditiocarbonatos alquílicos, R-O-CS2 –), se caracteriza mediante la técnica del ángulo de contacto. Los resultados muestran que el Cu(II) es intercambiado por el Zn de las capas exteriores del cristal, promoviendo la oxidación de sulfuro (S2–) para producir una mezcla de CuS, Cu2S y S°, de naturaleza hidrofóbica. La interacción posterior con el xantato, hace que la hidrofobicidad de la superficie se incremente. Por su parte, la activación con Pb(II) se debe a la formación de una capa de PbS, la cual reacciona espontáneamente con el xantato para producir especies hidrofóbicas (e.g., PbX2). Se observa que la hidrofobización de la esfalerita acondicionada con Pb(II) se favorece en atmósferas de aire, en comparación con la obtenida en atmósferas de nitrógeno. Se concluye que la hidrofobización alcanzada de manera inadvertida con el Pb(II), puede llegar a ser del mismo orden de magnitud que la hidrofobización inducida deliberadamente mediante la activación con cobre.
Modelo predictivo de control en fundiciones de alta precisión: un nuevo enfoque para la fase de predicción
Authors: Nieves J. , Santos I. , Bringas P. G.
Published: September 2011

Un Modelo Predictivo de Control (MPC) es un sistema que permite llevar a cabo el control de una planta de producción. Gracias a este tipo de sistemas es posible realizar una producción que se aproxime al “cero defectos”. Para poder desempeñar su labor fundamental, este tipo de sistemas se compone de varias fases o etapas. Una de las más importantes es la fase que permite predecir la situación en la que se va a encontrar la planta en un momento dado. La mayoría de los avances realizados en este campo han estado ligados a los MPC lineales, a pesar de que el proceso que se intenta representar no lo sea. Así, en este artículo, se presentan varios experimentos que permiten demostrar que la etapa de predicción, habitualmente representada por una única función matemática, puede ser representada mediante modelos de aprendizaje automático.
Design of Ternary Clocked Adiabatic Synchronous Reversible Counter
Authors: Mei Feng Na , Wang Peng Jun
Published: September 2011

Based on the study of synchronous counter and adiabatic circuits, a new design scheme of ternary adiabatic synchronous reversible counter is proposed. According to the theory of three essential circuit elements, circuit structure of four-bit ternary adiabatic synchronous reversible counter is realized by using NMOS transistors with different thresholds and cross-storage structure and combining with the principle of energy recovery. Computer simulation results indicate that the designed circuits have correct logic function. Compared with traditional CMOS counter, the average power consumption of circuits saves up to 67.5%.
Research on Coal Mine Roadway Safety Monitoring System Based on Zigbee
Authors: Ma Ying , Ma Xiao Yu , Wang Guo Dong
Published: September 2011

With the higher and higher demands to the safety in coal mines and the development of the enterprises themselves, the security problems in coal mines already become the most important ones. Because of many hidden dangers existing in coal mines, the accidents that make the heavy economic losses and personnel casualty occurs frequently in China coal mines. It shows that the existing safety monitoring systems in coal mines has some insufficiencies. By researching on the collection of human physiology information, the design of wireless sensor network node and wireless networking technology, the system applies ZigBee technology into the environment of coal mine roadway safety production, which realizes the detecting of daily work environment of coal mine roadway as well as the real time monitoring of the location and status of the trapped people underground when safety accident happens so as to provide accurate information for rescue.