The impact of socioeconomic status on hand injury severity.

Socioeconomic status (SES) is an important factor affecting different aspects of human health, including self-care and healthcare service use. The relation between SES and hand injury severity is not well defined; therefore, the present study aimed to investigate the relation between SES and hand injury severity. This cross-sectional descriptive and analytical study included 215 patients with hand injury. Demographic, clinical, and SES-related factors were collected by questionnaire. Injury severity was assessed on Hand Injury Severity Score (HISS). Statistical analysis used the Student t-test, chi-square test and a multinomial regression model to calculate the odds ratio (OR) of each predictive factor. Mean age was 38.02 ± 13.49 years (range, 12-80 years). 73.5% of the participants were men. Patients with low SES were significantly more likely to develop severe hand injury (OR = 5.25 and 9.25 at HISS levels 3 and 4, respectively). In addition, there was a significant association between being born in rural areas and severe (HISS level 3, OR = 2.63) or major (HISS level 4, OR = 2.63) hand injury. Also, major (HISS level 4) hand injuries were significantly more prevalent in patients living in rural areas (OR = 4.23) and those injured in road accidents (OR = 1.98) or practicing sports (OR = 3.51). The study concluded that patients with low SES were 5-10-fold more likely to suffer from severe and major hand injuries, and thus provided valuable information for Iranian policymakers to take preventive measures for hand injuries. It is recommended to improve postoperative care in patients with low SES who underwent hand surgery, take the necessary measures to decrease the incidence of road accident injuries, facilitate early referral of patients with hand injury to trauma centers, and improve postoperative follow-up until full recovery. LEVEL OF EVIDENCE: III.

Distinct critical behaviors from the same state in quantum spin and population dynamics perspectives.

There is a deep connection between the ground states of transverse-field spin systems and the late-time distributions of evolving viral populations-within simple models, both are obtained from the principal eigenvector of the same matrix. However, that vector is the wave-function amplitude in the quantum spin model, whereas it is the probability itself in the population model. We show that this seemingly minor difference has significant consequences: Phase transitions that are discontinuous in the spin system become continuous when viewed through the population perspective, and transitions that are continuous become governed by new critical exponents. We introduce a more general class of models that encompasses both cases and that can be solved exactly in a mean-field limit. Numerical results are also presented for a number of one-dimensional chains with power-law interactions. We see that well-worn spin models of quantum statistical mechanics can contain unexpected new physics and insights when treated as population-dynamical models and beyond, motivating further studies.

Folding and unbinding transitions in tethered membranes.

Molecular dynamics simulations of tethered membranes indicate that an attraction between the monomers leads to a well-defined sequence of folding transitions with decreasing temperature. With insights gained from Landau theory and simulations of bimembranes, the folding transitions are found to be intimately linked to the unbinding of membranes. Finite-size effects, mainly due to the loss of entropy from edge fluctuations, play an important role in hindering folding transitions.

Dynamics of tumor growth and combination of anti-angiogenic and cytotoxic therapies.

Tumors cannot grow beyond a certain size (about 1-2 mm in diameter) through simple diffusion of oxygen and other essential nutrients into the tumor. Angiogenesis, the formation of blood vessels from pre-existing vessels, is a crucial and observed step, through which a tumor obtains its own blood supply. Thus, strategies that interfere with the development of this tumor vasculature, known as anti-angiogenic therapy, represent a novel approach to controlling tumor growth. Several pre-clinical studies have suggested that currently available angiogenesis inhibitors are unlikely to yield significant sustained improvements in tumor control on their own, but rather will need to be used in combination with conventional treatments to achieve maximal benefit. Optimal sequencing of anti-angiogenic treatment and radiotherapy or chemotherapy is essential to the success of these combined treatment strategies. Hence, a major challenge to mathematical modeling and computer simulations is to find appropriate dosages, schedules and sequencing of combination therapies to control or eliminate tumor growth. Here, we present a mathematical model that incorporates tumor cells and the vascular network, as well as their interplay. We can then include the effects of two different treatments, conventional cytotoxic therapy and anti-angiogenic therapy. The results are compared with available experimental and clinical data.

Fractional Laplacian in bounded domains.

The fractional Laplacian operator -(-delta)(alpha/2) appears in a wide class of physical systems, including Lévy flights and stochastic interfaces. In this paper, we provide a discretized version of this operator which is well suited to deal with boundary conditions on a finite interval. The implementation of boundary conditions is justified by appealing to two physical models, namely, hopping particles and elastic springs. The eigenvalues and eigenfunctions in a bounded domain are then obtained numerically for different boundary conditions. Some analytical results concerning the structure of the eigenvalue spectrum are also obtained.

Optimal paths on the road network as directed polymers.

We analyze the statistics of the shortest and fastest paths on the road network between randomly sampled end points. We find that, to a good approximation, the optimal paths can be described as directed polymers in a disordered medium, which belong to the Kardar-Parisi-Zhang universality class of interface roughening. Comparing the scaling behavior of our data with simulations of directed polymers and previous theoretical results, we are able to point out the few characteristics of the road network that are relevant to the large-scale statistics of optimal paths. Indeed, we show that the local structure is akin to a disordered environment with a power-law distribution which become less important at large scales where long-ranged correlations in the network control the scaling behavior of the optimal paths.

Thermodynamic fingerprints of disorder in flux line lattices and other glassy mesoscopic systems

We examine probability distributions for thermodynamic quantities in finite-sized random systems close to criticality. Guided by available exact results, a general ansatz is proposed for replicated free energies, which leads to scaling forms for cumulants of various macroscopic observables. For the specific example of a planar flux line lattice in a two-dimensional superconducting film near H(c1), we provide detailed scaling results for the statistics of the magnetic flux density, susceptibility, heat capacity, and their cross correlations, which can be tested in a recently used experimental setup [Bolle et al., Nature (London) 399, 43 (1999)].

Triterpenoids from Lawsonia alba.

Two pentacyclic triterpenoids have been isolated from the aerial parts of Lawsonia alba. The structures of the new constituents, named as lawsonic acid and lawsonin have been elucidated as 3 alpha-E-ferulyloxy-lup-20(29)-en-28-oic acid and 3 alpha-E-ferulyloxy-urs-11-en-13 beta-ol respectively through spectroscopic studies.

Macroscopic equations for pattern formation in mixtures of microtubules and molecular motors.

Inspired by patterns observed in mixtures of microtubules and molecular motors, we propose continuum equations for the evolution of motor density and microtubule orientation. The chief ingredients are the transport of motors along tubules, and the alignment of tubules in the process. The macroscopic equations lead to aster and vortex patterns in qualitative agreement with experiments. While the early stages of evolution of tubules are similar to coarsening of spins following a quench, the rearrangement of motors leads to arrested coarsening at low densities. Even in one dimension, the equations exhibit a variety of interesting behaviors, such as symmetry breaking, moving fronts, and motor localization.

Characterisation of triterpenes and new phenolic lipids in Cameroonian propolis.

Chemical investigation of a sample of propolis originating from North-Western Cameroon led to the isolation of thirteen alk(en)ylphenols (1-13) (inseparable mixture) along with α-amyrin (14), ß-amyrin (15), lupeol (16), cycloartenol (17), mangiferonic acid (18), ambonic acid (19), mangiferolic acid (20), ambolic acid (21), isomangiferolic acid (22) and nine alk(en)ylresorcinols (23-31) (inseparable mixture). All compounds were identified following analysis of their spectroscopic data and comparison with previously published reports. Compounds (8), (12), (13) and (30) are new natural products. GC-MS analysis carried out on the alk(en)ylphenol and alk(en)ylresorcinol mixtures (dimethyl disulphide trimethylsilyl derivatives) revealed the presence of saturated and mono-unsaturated compounds with side chain lengths ranging from C11 to C19 and C15 to C19, respectively. The position of the double bond in mono-unsaturated derivatives was established from the characteristic fragments resulting from the cleavage of the bond between the two methylthio-substituted carbons. The most abundant compound in each mixture was 3-(12'Z-heptadecenyl)-phenol (10) and 5-(12'Z-heptadecenyl)-resorcinol (29). This study is the first to report the presence of triterpenes (except for lupeol) and phenolic lipids, including eighteen compounds previously unreported in bee glue, in an African sample.

Arbutin derivatives from the seeds of Madhuca latifolia.

A new arbutin derivative, madhuglucoside (1), along with three known arbutin derivatives were isolated from the seeds of Madhuca latifolia in addition to seven other known constituents. Their structures were established on the basis of spectral analysis. Compounds 1a, 2a and 3a were obtained in a pure state after acetylation of the mother fraction and characterized as their acetyl derivatives.

Quantitative model for efficient temporal targeting of tumor cells and neovasculature.

The combination of cytotoxic therapies and antiangiogenic agents is emerging as a most promising strategy in the treatment of malignant tumors. However, the timing and sequencing of these treatments seem to play essential roles in achieving a synergic outcome. Using a mathematical modeling approach that is grounded on available experimental data, we investigate the spatial and temporal targeting of tumor cells and neovasculature with a nanoscale delivery system. Our model suggests that the experimental success of the nanoscale delivery system depends crucially on the trapping of chemotherapeutic agents within the tumor tissue. The numerical results also indicate that substantial further improvements in the efficiency of the nanoscale delivery system can be achieved through an adjustment of the temporal targeting mechanism.

A new isoflavone from the fruits of Madhuca latifolia.

A new isoflavone, 3',4'-dihydroxy-5,2'-dimethoxy-6,7-methylendioxy isoflavone, was isolated from the Madhuca latifolia fruit coatings. The structure was elucidated on the basis of spectral and chemical evidence.