Nonintegrability of (2+1)-dimensional continuum isotropic Heisenberg spin system: Painlev\'e analysis

While many integrable spin systems are known to exist in (1+1) and (2+1) dimensions, the integrability property of the physically important (2+1) dimensional isotropic Heisenberg ferromagnetic spin system in the continuum limit has not been investigated in the literature. In this paper, we show through a careful singularity structure analysis of the underlying nonlinear evolution equation that the system admits logarithmic type singular manifolds and so is of non-Painlev\'e type and is expected to be nonintegrable.Comment: 11 pages. to be published in Phys. Lett. A (2006

Aesthetic Reconstruction of the Nose

INTRODUCTION: Occupying the most prominent position on the face, the nose has been the source of well known sayings “plain as a nose in a man’s face”. The central location and projection not only emphasize its aesthetic importance but alsocontribute to its frequent injury. The loss of each layer of the nose may be due to congenital, traumatic, infection or neoplasm and in the reconstruction each layer must be replaced. Reconstruction of the nose is one of the oldest form of facial reconstructive surgery, its complexity continue to challenge facial reconstructive surgeons. The nose to appear normal must have the proper dimensions, position and symmetry. Adequate osseocartilaginous support, internal nasal lining and the soft tissue cover are the requirements for re-establishing a functional airway. The external skin cover should be of similar colour and texture as the facial skin. Thoughtful consideration of the patient, the wound and the available donor materials help to identify the most appropriate treatment. AIM OF THE STUDY: To study the various techniques used in the reconstruction of defects of the nose and evaluate each technique. MATERIALS AND METHODS: 20 patients who required reconstruction of the nasal defects, presented to the Department Of Plastic, Reconstructive and Faciomaxillary Surgery, Madras Medical College, Rajiv Gandhi Government General Hospital, Chennai were included in the study and period ranging from October 2009- March 2012. The follow up of these patients ranged from 2 months to 24 months. Out of the 20 patients, 14 patients were female and the remaining 6 were male patients. Age ranging from 20-75 yrs. Of the 20 cases, post excision defect for malignancy accounted for 10 cases, defect following excision of benign lesion -6 cases and post-traumatic defects accounted for 4 cases. Full-thickness defects of the nose accounted for 6 cases, and skin cover only defects accounted for the rest of the cases. The site of the defect was found to be on the dorsum of the nose alone in 2 cases, dorsum and sidewall in 10 cases, tip, ala and columella in 4 cases and ala and dorsum in 4 cases. The post excisional defects following excision of the benign or malignant tumor were reconstructed primarily and were followed up regularly for recurrence. The post-traumatic defects were reconstructed secondarily. RESULTS: The results of the study were evaluated for aesthetic outcome following reconstruction with the local flaps .The flaps were evaluated for color match, contour and the need for secondary thinning of the flap. The defects reconstructed with forehead had excellent color match,but the junction of the flap and recipient site needed contouring in the form of thinning at a secondary stage. The nasolabial flap had excellent contour for the defect in the tip and ala of the nose ,but needed thinning to reduce the bulkiness of the flap used for the lining. During the follow-up period of 24 months the reconstructed nose retained the shape and tip projection. The pedicled flaps had no complications.One patient who had a subtotal nasal reconstruction with oblique paramedian forehead flap had the donor site skin grafted which reduced in size as there was graft contraction. All the cases operated for malignancy were followed for the biopsy report for the margins and regularly monitored for any recurrence.No case had any recurrence in the operated site. CONCLUSION: Aesthetic reconstruction of the nose is required in cases of nasal defects following trauma, tumour extirpation, congenital etc. The art of reconstruction of the nose is one of the oldest techniques in the field of plastic surgery with its initial roots in India, and the techniques continue to be modified to match the pre injury status of the patient. Small and medium sized defects of the nose requiring only the skin cover are best reconstructed by full-thickness grafts. Larger defects of the nose are reconstructed based on the component of the nose lost, and may require replacement of the lost tissues with lining, support and skin cover. The subunit principle is followed in the reconstruction in the large convex subunit areas of the nose to llow for a more natural appearance. Reconstruction of the nasal cover is of aesthetic importance with regard to the colour and the texture of the skin

Constructing Integrable Third Order Systems:The Gambier Approach

We present a systematic construction of integrable third order systems based on the coupling of an integrable second order equation and a Riccati equation. This approach is the extension of the Gambier method that led to the equation that bears his name. Our study is carried through for both continuous and discrete systems. In both cases the investigation is based on the study of the singularities of the system (the Painlev\'e method for ODE's and the singularity confinement method for mappings).Comment: 14 pages, TEX FIL

The Influence of High-Energy Lithium Ion Irradiation on Electrical Characteristics of Silicon and GaAs Solar Cells

Space-grade Si and GaAs solar cells were irradiated with 15 & 40 MeV Li ions. Illuminated (AM0 condition) and unilluminated I-V curves reveal that the effect of high-energy Li ion irradiation has produced similar effects to that of proton irradiation. However, an additional, and different, defect mechanism is suggested to dominate in the heavier-ion results. Comparison is made with proton-irradiated solar-cell work and with non-ionizing energy-loss (NIEL) radiation-damage models.Comment: 8 pages, 12 figures, Data presented at 2006 NSREC, Final Version to be published in IEEE Transactions on Nuclear Science, 53, NO. 6, December 2006. Index Terms: GaAs, Ion-irradiation, Lithium, NIEL, Photovoltaic cells, Radiation effects, Silico

COMPARATIVE STUDY ON ANTIMICROBIAL ACTIVITY OF SEAWEEDS

Objective: Secondary metabolites from natural resources are a potential source of antimicrobial leads and drugs can exploited to combat antimicrobial resistance in microorganisms. Seaweeds are considered as a valuable source with a broad spectrum of biological activities. Hence, this study was undertaken to screen seaweeds from Mandapam coastal waters, East coast of India, for antimicrobial activity.Methods: Compounds were extracted using methanol from the seaweeds, namely, Halimeda gracilis, Caulerpa serrulata, Sargassum swartzii, Sargassum wightii, Jania rubens, Ulva lactuca, Ulva fasciata, Gracilaria corticata, Stoechospermum marginatum, Caulerpa scalpelliformis, Caulerpa taxifolia, Chaetomorpha crassa, Enteromorpha flexuosa, and Turbinaria ornate. The extracts were screened for their antimicrobial activity against selected bacterial and fungal pathogens.Results: In the present study, S. swartzii, J. rubens, and S. marginatum showed broad spectrum of antibacterial activity against all the test bacterial pathogens. Among these, the maximum activity was exhibited by S. swartzii against Enterococcus faecalis (27.00 ± 0.88) and Streptococcus pyogenes (23.00 ± 0.84), followed by J. rubens against E. faecalis (26.00 ± 0.56) and S. pyogenes (22.00 ± 0.75), and S. marginatum exhibited significant inhibition against Staphylococcus aureus (15.00 ± 0.22) and S. pyogenes (18.00 ± 1.16).Conclusion: These seaweeds with significant antibacterial activity will subjected to phytochemical screening to find out the potential active principle responsible for antimicrobial activity. It is followed by purification and characterization of the compounds for possible application in drug formulation, can take this to large-scale application in pharmaceutical industries

Robert’s uterus: a rare mullerian anomaly mystery unfolded

Anomalies of female genital tract may not be detected until after menarche when they present a cyclical pain due to outlet obstruction. Mullerian anomalies represent a vast array of structural abnormalities resulting from improper development and fusion of embryological mullerian ducts. 19-year-old girl attained menarche at the age of 14, had progressive dysmenorrhoea and diagnosed as right haemotosalphinx and ovarian endometrioma which were removed in 2008. As pain progressed, she underwent laparoscopic adhesiolysis in 2013. Since, pain persisted, diagnosed as right haematometra, and drainage done by laparotomy. Left adnexa were normal. She was given depot provera till she completed schooling. She developed recurrent dysmenorrhoea after stopping depot provera. USG and MRI revealed recurrent haematometra on right side with normal left horn. The possibility of atypical septum was thought about and hystero laparoscopy was done. It showed right side haemetometra with absent right adnexa. Left adnexa normal. Hysteroscopy showed normal left horn with septum with a bulge towards the left side. Hence, proceeded with hysteroscopic septostomy and haemetometra was drained to the left horn. Later patient was free from dysmenorrhea and repeat hysteroscopy was found to be normal. This case highlighting mullerian anomalies have to be considered when young girls present with severe progressive dysmenorrhoea and diagnosis remains a challenge most of the clinicians. This rare entity has to be kept in mind while evaluating such patients. Prompt diagnosis and early surgical correction are essential to avoid future morbidity in the form of repeated unnecessary surgeries

Solvable Chaos

We present classes of discrete reversible systems which are at the same time chaotic and solvable

An interesting case of Phocomelia

Authors present a very rare case of tetra-phocomelia evaluated by antenatal ultrasonography. It is a condition seen in 0.62 per 100,000 live births. This is a congenital chromosomal abnormality involving the musculoskeletal system. Primi gravida with spontaneous conception after a long period of infertility underwent early anomaly scan. Patient was not aware of the last menstrual period hence; NT scan was missed. Routine early anomaly scan done between 16-18 weeks of pregnancy diagnosed a fetus with Tetra-Phocomelia. Due to the lack of associated symptoms or significant history, our case did not fit into any specific syndrome and appears to be the result of a sporadic, non-hereditary limb deficiency involving all four limb buds.  Second opinion obtained from a fetal medicine consultant who confirmed the diagnosis. Hence, decided for mid trimester termination and fetus was expelled after 8 hours. Fetus was not sent for pathological analysis. Tetra-phocomelia is a rare congenital anomaly and it may be associated with other deformity also. 1st case of phocomelia was described after the intake of thalidomide. In this condition hands and feet are seen as small flippers of a seal. The differential diagnosis includes sporadic phocomelia, Holt-Oram syndrome, thrombocytopenia-absent radius syndrome (TAR syndrome), Robert’s syndrome, and thalidomide-induced phocomelia. Here authors are presenting a rare case of Phocomelia where there is no history of drug intake or family history. This has to differentiate from thrombocytopenia-absent radius syndrome (TAR syndrome), sporadic phocomelia, Holt-Oram syndrome, Robert’s syndrome, and thalidomide-induced phocomelia

Umbilical endometriosis along with peritoneal endometriosis: a case report

Incidence of endometriosis is around 10 to 15% in women of reproductive age group. Umbilical endometriosis is a very rare entity. Extra genital endometriosis accounts to 3% of endometriosis. Incidence of umbilical endometriosis is 0.5%-4% of extra genital endometriosis. 30 years old multi gravida was referred to our hospital with c/o periodic bleeding from the umbilicus for the past 3 months. She was also having dysmenorrhoea for about 3 months. On examination, patient had a small bluish nodule in the umbilicus around 1.5x1.2 cm in size. Clinically there was suspicion of pelvic endometriosis as the uterus was retroverted and fixed. CT abdomen showed a small hypo-echoeic area in the umbilicus and uterus was adenomyotic with normal ovaries. Patient was given the option of laparoscopy and excision of umbilicus, as there was suspicion of peritoneal endometriosis and the patient also insisted upon laparoscopic sterilization. Laparoscopy showed early peritoneal endometriosis with pelvic adhesions and the same adhesiolysis was done along with cauterization of endometriosis. Sterilization was also done as per the patient’s request. Umbilical excision and layer closure was done. Umbilical endometriosis is a rare entity. This patient had associated early pelvic endometriosis. Umbilical endometriosis could be secondary to the lympho vascular spread from the pelvic endometriosis or primary umbilical endometriosis. History, clinical and imaging were pointing towards umbilical endometriosis. Surgical excision of umbilical endometriosis and cauterisation of early pelvic endometriosis were done. Patient needs follow up. Umbilical endometriosis may be primary or secondary which needs total excision and follow up