Interactive effects of vegetation and sediment properties on erosion of salt marshes in the Northern Adriatic Sea.

We investigated how lateral erosion control, measured by novel photogrammetry techniques, is modified by the presence of Spartina spp. vegetation, sediment grain size, and the nutrient status of salt marshes across 230 km of the Italian Northern Adriatic coastline. Spartina spp. vegetation reduced erosion across our study sites. The effect was more pronounced in sandy soils, where erosion was reduced by 80% compared to 17% in silty soils. Erosion resistance was also enhanced by Spartina spp. root biomass. In the absence of vegetation, erosion resistance was enhanced by silt content, with mean erosion 72% lower in silty vs. sandy soils. We found no relevant relationships with nutrient status, likely due to overall high nutrient concentrations and low C:N ratios across all sites. Our results contribute to quantifying coastal protection ecosystem services provided by salt marshes in both sandy and silty sediments.

The use of smartphones on General Internal Medicine wards: a mixed methods study.

OBJECTIVE: To describe the uses of institutional and personal smartphones on General Internal Medicine wards and highlight potential consequences from their use. METHODS: A mixed methods study consisting of both quantitative and qualitative research methods was conducted in General Internal Medicine wards across four academic teaching hospitals in Toronto, Ontario. Participants included medical students, residents, attending physicians and allied health professionals. Data collection consisted of work shadowing observations, semi-structured interviews and surveys. RESULTS: Personal smartphones were used for both clinical communication and non-work-related activities. Clinicians used their personal devices to communicate with their medical teams and with other medical specialties and healthcare professionals. Participants understood the risks associated with communicating confidential health information via their personal smartphones, but appear to favor efficiency over privacy issues. From survey responses, 9 of 23 residents (39%) reported using their personal cell phones to email or text patient information that may have contained patient identifiers. Although some residents were observed using their personal smartphones for non-work-related activities, personal use was infrequent and most residents did not engage in this activity. CONCLUSION: Clinicians are using personal smartphones for work-related purposes on the wards. With the increasing popularity of smartphone devices, it is anticipated that an increasing number of clinicians will use their personal smartphones for clinical work. This trend poses risks to the secure transfer of confidential personal health information and may lead to increased distractions for clinicians.

Critical care management of patients with acute spinal cord injury.

Spinal cord injury (SCI) inevitably extends beyond neurologic consequences. The relationship between the spinal cord and its control of other organ systems make SCI management complex, requiring treatment on a multisystem approach. Patients frequently have hemodynamic instability and respiratory insufficiency secondary to the neurologic insult. Rigorous monitoring and anticipation of potential complications are essential in managing SCI, requiring a level of care provided in a neurocritical care unit. This review covers the pathophysiology, initial assessment, and stabilization in addition to acute management of cardiovascular and respiratory issues following SCI. Subsequent potential complications of deep vein thrombosis, gastrointestinal, and urinary systems and their management in the critical care setting are also addressed in this review.

The 4G/4G genotype of the PAI-1 (serpine-1) 4G/5G polymorphism is associated with decreased lung allograft utilization.

Widespread thrombi are found among donor lungs rejected for transplantation. The 4G/5G polymorphism in the plasminogen activator inhibitor (PAI-1) gene impacts transcription and the 4G allele is associated with increased PAI-1 levels. We hypothesized that the 4G/4G genotype would be associated with decreased lung graft utilization, potentially because of worse oxygenation in the donor. We genotyped donors managed by the California Transplant Donor Network from 2001 to 2008 for the 4G/5G polymorphism in the PAI-1 gene. Non-Hispanic donors from 2001 to 2005 defined the discovery cohort (n = 519), whereas donors from 2006 to 2008 defined the validation cohort (n = 369). We found, that the odds of successful lung utilization among Non-Hispanic white donors were lower among donors with the 4G/4G genotype compared to those without this genotype in both the discovery (OR = 0.55, 95% CI = 0.3-0.9, p = 0.02) and validation (OR = 0.5, 95% CI = 0.3-0.9, p = 0.03) cohorts. This relationship was independent of age, gender, cause of death, drug use and history of smoking. Donors with the 4G/4G genotype also had a lower PaO2/FiO2 ratio (p = 0.03) and fewer donors with the 4G/4G genotype achieved the threshold PaO2/FiO2 ratio ≥ 300 (p = 0.05). These findings suggest a role for impaired fibrinolysis resulting in worse gas exchange and decreased donor utilization.

Understanding interprofessional communication: a content analysis of email communications between doctors and nurses.

BACKGROUND: Clinical communication is recognized as a major source of errors in hospitals. The lack of documentation of communication, especially among verbal interactions, often creates hindrances and impedes improvement efforts. By providing smartphones to residents and encouraging nurses to communicate with residents by email shifted much of the communication to emails which permitted analysis of content. OBJECTIVE: Description on the interprofessional email communication between doctors and nurses occurring on the general internal medicine wards at two academic hospitals. DESIGN: A prospective analysis of email communications between doctors and nurses. SETTING: 34 out of the 67 residents who were on the general medicine clinical teaching units consented to allow analysis of their emails over a 6 month period. MAIN MEASURES: Statistical tabulations were performed on the volume and frequency of communications as well the response time of messages. Two physicians coded the content of randomly selected emails for urgency, emotion, language, type of interaction, and subject content. KEY RESULTS: A total of 13,717 emails were available for analysis. Among the emails from nurses, 39.1% were requests for a call back, 18.9% were requests for a response by email and the remaining 42.0% indicated no response was required from physicians. For the messages requesting a response by email, only 50% received an email response. Email responses had a median response time of 2.3 minutes. Content analysis revealed that messages were predominantly non-urgent. The two most frequent purposes for communications were to convey information (91%) and to request action by the physician (36%). CONCLUSIONS: A smartphone-based email system facilitated the description and content analysis of a large amount of email communication between physicians and nurses. Our findings provide a picture of the communication between physicians, nurses and other healthcare professionals. This work may help inform the further development of information and communications technology that can improve clinical communication.

Local treatment of mixed osteolytic/osteoblastic spinal metastases: is photodynamic therapy effective?

The widespread use of systemic and local therapies aimed at spinal metastatic lesions secondary to breast cancer has increased the incidence of mixed osteolytic/osteoblastic patterns of bony disease. The complex structure of these lesions requires novel therapeutic approaches to both reduce tumor burden and restore structural stability. In photodynamic therapy (PDT), a minimally invasive approach can be used to employ light to activate a photosensitizing agent that preferentially accumulates in tumor tissue, leading to cell toxicity and death. Previous work in an osteolytic rat model (MT-1) demonstrated that PDT effectively ablates tumor and improves vertebral structural properties. The aim of this study was to assess the efficacy of PDT in a rat model of mixed osteolytic/osteoblastic spinal metastases. Mixed spinal metastases were generated through intracardiac injection of Ace-1 canine prostate cancer cells into female athymic rats (day 0). A single PDT treatment was applied to lumbar vertebra L2 of tumor-bearing and healthy control rats (day 14). PDT-treated and untreated control rats were euthanized and excised spines imaged with µCT to assess bone quality (day 21). Spines were mechanically tested or histologically processed to assess mechanical integrity, tumor burden, and remodelling properties. Untreated tumor-bearing vertebrae showed large areas of osteolysis and areas of immature, new bone formation. The overall bone quality resulting from these lesions consisted of decreased structural properties but without a significant reduction in mechanical integrity. PDT was shown to significantly decrease tumor burden and osteoclastic activity, thereby improving vertebral bone structural properties. While non-tumor-bearing vertebrae exhibited significantly more new bone formation following PDT, the already heightened level of new bone formation in the mixed tumor-bearing vertebrae was not further increased. As such, the effect of PDT on mixed metastases may be more influenced by suppression of osteoclastic resorption as opposed to the triggering of new bone formation.

First-principles study of the structural, elastic, and electronic properties of C(20), C(12)B(8), and C(12)N(8).

First-principles calculations were performed to study the structural, elastic, and electronic properties of the crystalline form of C(20), C(12)B(8), and C(12)N(8). These compounds exhibit very different elastic and electronic properties. The shear modulus of C(12)N(8) is much higher than those of C(20) and C(12)B(8). The strong covalent C-N interaction plays an important role in this high shear modulus. Compared with C(20), the relatively small Zener anisotropy of C(12)N(8) is mainly due to its large elastic constant (C(11) - C(12)). The calculated band structure shows that C(12)N(8) is an insulator with a direct band gap of 3 eV and the other two compounds (C(20) and C(12)B(8)) are metallic. Analysis of the band structure, density of states, and charge density show that the degree of filling in the non-bonding 2p(z) strongly affects the electronic properties. The full filling of the non-bonding orbital for C(12)N(8) results in its insulating behavior.

The Ste20-like kinase SLK is required for ErbB2-driven breast cancer cell motility.

The Ste20-like kinase, SLK, is involved in the control of cell motility through its effects on actin reorganization and focal adhesion turnover. Here we investigated the role of SLK in chemotaxis downstream of the tyrosine kinase receptor, HER2/ErbB2/Neu, which is frequently overexpressed in human breast cancers. Our results show that SLK is required for the efficient cell migration of human and mouse mammary epithelial cell lines in the presence of the Neu activator, heregulin, as a chemoattractant. SLK activity is stimulated by heregulin treatment or by overexpression of activated Neu. Phosphorylation of tyrosine 1201 or tyrosines 1226/7 on Neu is a key event for SLK activation and cell migration, and cancer cell invasion mediated by these tyrosines is inhibited by kinase-inactive SLK. Signaling pathway inhibitors show that Neu-mediated SLK activation is dependent on MEK, PI3K, PLCgamma and Shc signaling. Furthermore, heregulin-stimulated SLK activity requires signals from the focal adhesion proteins, FAK and src. Finally, phospho-FAK analysis shows that SLK is required for Neu-dependent focal adhesion turnover. Together, these studies define an interaction between Neu and SLK signaling in the regulation of cancer cell motility.

Reconstruction of compact binary images from limited Fourier amplitude data.

The problem of reconstructing a binary image from undersampled Fourier amplitude data is considered. This problem maps to an image reconstruction problem in x-ray crystallography. The binary constraint is sufficient to overcome the undersampling and enforce uniqueness, but is insufficient in the case of the additional loss of data that can occur in practice. An iterative projection algorithm is developed that uses binary, connectivity, and compactness constraints to solve the image reconstruction problem. Simulations show the utility of the reconstruction algorithm.

The effects of hydraulic retention time and loading rate on brewery wastewater treatment using sequencing batch reactors.

Four laboratory-scale suspended-growth aerobic sequencing batch reactors (SBR) were used to study the effects of hydraulic retention time (HRT) and loading rate on the treatment of brewery wastewater. Factorial experiments and response surface analysis were carried out to explore the optimal operating conditions. A maximum total organic carbon (TOC) removal of 97% was estimated, at a HRT of 1.44 days with a loading rate of 3122 mg/L day. The maximum suspended solids removal, around 95%, would occur at values of HRT and loading rate of 1.32 days and 13.84 g/L day, respectively. TOC removal was more sensitive to the variations of HRT, however, the loading rate was more important than the HRT for suspended solids removal.

Synthesis and DNA nicking studies of a novel cyclic peptide: cyclo[Lys-Trp-Lys-Ahx-].

Two novel cyclic tetrapeptides: cyclo[Lys-Tyr-Lys-Ahx-] 7a and cyclo[Lys-Trp-Lys-Ahx-] 7b were synthesized by coupling protected amino acid in solution and the subsequent cyclization effected by the pentafluorophenyl ester method as described in previous papers. These cyclic peptides were designed and synthesized to study their interaction with DNA, based on previous reports that linear peptides Lys-Tyr-Lys and Lys-Trp-Lys could bind to various forms of DNA and cleaved supercoiled DNA at apurinic sites. Ethidium bromide displacement assay showed that the apparent DNA binding constant of linear Lys-Tyr-Lys and cyclic peptide 7a are far below 1 x 10(3) M(-1), whereas those of cyclic peptide 7b and linear Lys-Trp-Lys are 1.9 x 10(4) M(-1) and 9.5 x 10(3) M(-1), respectively. Kinetic studies using agarose gel electrophoresis showed that cyclic peptide 7b and Lys-Trp-Lys possessed DNA nicking activity on natural supercoiled phi X174 DNA with nicking rate of 50.7 and 75.6 pM min(-1) at 65 degrees C, respectively, whereas cyclic peptide 7a and linear Lys-Tyr-Lys were devoid of the corresponding activity. The DNA nicking rate increased significantly with increase in reaction temperature. At reaction temperatures lower than 65 degrees C, the DNA nicking rate of cyclic peptide 7b exceeded that of linear Lys-Trp-Lys. The addition of 1 microM ferrous ion did not give significant enhancement effect on the DNA nicking rate by the peptides. UV irradiation gave a marked rate enhancement on the DNA nicking rate of linear Lys-Trp-Lys and a moderate enhancement on the DNA nicking rate of cyclic peptide 7b.

Patient education and the prevention of incisional hernia.

Laparoscopic or 'key hole' surgery has become an acceptable technique for abdominal surgery. This technique is utilised by surgeons who work in tertiary hospitals as well as those in private, day only, surgical facilities. Despite the increasing use of this technique in Australia, a paucity of information is available in the journals about the real or potential complications the patient may suffer following this method of surgery. The first author of this paper who works in the operating room practice domain, observed over three years a number of patients readmitted for repair of incisional hernia following abdominal laparoscopic surgery. A review of the international literature and dialogue with operating nurses from institutions in Sydney and Hong Kong confirmed there was enough evidence to warrant examining the complication of incisional hernia as a clinical problem. It would appear from the literature that incidence rate is unknown in Australia. Several reasons may account for this. First, it appears that few surgeons are documenting patient outcomes of laparoscopic surgery, not withstanding the proliferation of its use in the last five years. The second possible reason is the paucity of published information available in the journals, perhaps because the technique is still viewed as relatively new and experimental. This paper outlines a brief history of laparoscopic surgery and some responsibilities nurses have in relation to patient education and the prevention of post-operative complications.

Synthesis, DNA cleavage and cytotoxicity of some novel cyclic peptide-2,6-dimethoxyhydroquinone-3-mercaptoacetic acid conjugates containing D-amino acids.

This paper reports an ongoing study of the use of small-ring-size cyclic peptides as carriers of a potential antitumor agent: 2,6-dimethoxyhydroquinone-3-mercaptoacetic acid (DMQ-MA). Three new cyclic tripeptide-DMQ-MA conjugates--cyclo[D-Val-Lys(DMQ-MA)-gamma-aminobutyric acid (GABA)-], cyclo[Val-Lys(DMQ-MA)-GABA-] and cyclo[D-Val-D-Lys(DMQ-MA)-GABA-]--were synthesized. The isomeric cyclic tripeptide-DMQ-MA conjugates were designed and synthesized to study the effect of stereoisomerism of the conjugates on cytotoxicity. The cyclic peptides were synthesized by coupling protected amino acids in solution and the final cyclization performed by the pentafluorophenyl ester method as described previously. After removing the lysyl-Z protecting group of the cyclic peptides the conjugation was achieved by reacting with the pentafluorophenyl ester of DMQ-MA. Electron spin resonance (ESR) studies of these three cyclic tripeptide-DMQ-MA conjugates showed that hydroxyl radicals were generated as a non-linear function of L-ascorbic acid (AH2) concentration. The IC50 of the cyclic tripeptide-DMQ-MA conjugates against a human pulmonary carcinoma cell line (PC-9 cells) under the synergistic activation of AH2 ranges from 0.4 to 1.6 microM, which is significantly lower than the parent compound DMQ-MA (6.1 microM). Agarose gel electrophoresis showed that DMQ-MA and these cyclic peptide-DMQ-MA conjugates are capable of cleaving supercoiled plasmid DNA to open circular and linear forms, even in the absence of AH2. The effects of enantiomeric and diastereomeric variations of these cyclic tripeptide-DMQ-MA conjugates on the cytotoxicity against PC-9 cells were discussed.

Dynamics of an ultrasonic transducer used for wire bonding.

The vibration displacement distributions along a transducer used in ultrasonic wire bonding were measured using a heterodyne interferometer, and many nodes and anti-nodes were found. A mechanical finite element method (FEM) was used to compute the resonant frequencies and vibration mode shapes. The displacement distributions of the dominant 2nd axial mode agreed well with the measured values. Undesirable nonaxial modes, including the higher order flexural and torsional modes, also were excited at frequencies very close to the working frequency (2nd axial mode) of the transducer. Hence, the measured displacements were the resultant of all the allowable modes being excited. However, the excitation of these nonaxial modes were small enough not to affect the formation of consistent and high quality wire bonds. Results of the present study were used to determine a suitable location for installing a piezoelectric sensor to monitor the bond quality.

Distribution of calcitonin gene-related peptide-like immunoreactivity in the medulla oblongata of the cat, in relation to choline acetyltransferase-immunoreactive motoneurones and substance P-immunoreactive fibres.

The immunohistochemical distribution of calcitonin gene-related peptide (CGRP)-like immunoreactivity (ir) in the cat medulla oblongata was examined using an antiserum to rat alpha-CGRP. Comparative distributions of substance P (SP)-like and choline acetyltransferase (ChAT)-like ir were also studied on sections adjacent to those stained for CGRP, and on sections simultaneously stained for CGRP by double staining techniques. The vast majority of ChAT-ir motoneurones in somatomotor or branchiomotor cranial nuclei (of VI, VII and XII nerves) and their accessory nuclei also displayed a coarsely granular CGRP-ir, shown by electron microscopic examination to represent immunoreactive Golgi bodies. The nucleus ambiguus (IX and X nerves), a mixed branchiomotor and visceromotor nucleus, showed CGRP-ir in a lower proportion of its motoneurones, whereas the purely viseromotor dorsal motor vagal nucleus (X nerve) contained no CGRP-ir cells. A few CGRP-ir but ChAT-negative cells were seen in the ventromedial reticular formation, lateral cuneate nucleus, infratrigeminal nucleus and nucleus of the solitary tract. Coarse, often varicose CGRP-ir fibres were most prominent in the X and IX cranial nerve rootlets, the spinal tract of the V nerve and the solitary tract, and also in the V spinal nucleus and nucleus of the solitary tract. Many of these also appeared to contain SP-ir. The central patterns of CGRP and SP-ir fibres thus reflect the previously reported coexistence of these peptides in sensory afferent cells of the trigeminal and nodose ganglia. These results are consistent with a role for CGRP as a transmitter or modulator in efferents to striated muscle, sensory afferents and intrinsic neurones in the cat brain stem.