Dataset of cattle biometrics through muzzle images

The Cattle Biometrics Dataset is the result of a rigorous process of data collecting, encompassing a wide range of cattle photographs obtained from publicly accessible cattle markets and farms. The dataset provided contains a comprehensive collection of more than 8,000 annotated samples derived from several cow breeds. This dataset represents a valuable asset for conducting research in the field of biometric recognition. The diversity of cattle in this context includes a range of ages, genders, breeds, and environmental conditions. Every photograph is taken from different quality cameras is thoroughly annotated, with special attention given to the muzzle of the cattle, which is considered an excellent biometric characteristic. In addition to its obvious practical benefits, this dataset possesses significant potential for extensive reuse. Within the domain of computer vision, it serves as a catalyst for algorithmic advancements, whereas in the agricultural sector, it augments practises related to cattle management. Machine learning aficionados highly value the use of machine learning for the construction and experimentation of models, especially in the context of transfer learning. Interdisciplinary collaboration is actively encouraged, facilitating the advancement of knowledge at the intersections of agriculture, computer science, and data science. The Cattle Biometrics Dataset represents a valuable resource that has the potential to stimulate significant advancements in various academic disciplines, fostering ground breaking research and innovation.

Baseline assessment of water quality and ecological indicators in Penaeus vannamei farm wastewater along the Southeast coast of India

The present study aimed to investigate the water quality characteristics and the ecological indicators of wastewater of white legged shrimp Penaeus vannamei ponds along the Southeast coast of India. The wastewater samples were collected from 15 shrimp farms covering 11 districts located along the coastal line of Tamil Nadu and Puducherry, India. By adopting standard methods, the collected samples were subjected to analyses of physico-chemical and biological characteristics, especially the microbial load and metal and plankton composition. The nitrate-nitrogen, ammonia-nitrogen, THB, TCB, and Cu concentrations of the samples were found to exceed the permissible limit as recommended by WHO, USEPA, CPCB, and CAA. Principal component analysis and canonical correspondence analysis have suggested that the phosphate, nitrate, silicate, ammonia, and total phosphorus are the important chemical factors. The generated data would be of interest to farmers for their shrimp crop management vis-à-vis culture pond wastewater treatment.

Hand Sewn versus Stapled Closure of Duodenal Stump after Gastric Resection

This prospective comparative study was done to compare the outcome of stapled closure of the duodenal stump with hand-sewn closure during gastric resection in terms of total operating time, postoperative duodenal stump leakage, postoperative hospital stay, and surgical cost. This study was conducted from January 2013 to August 2014. Patients who were admitted to the Department of Surgery, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh with the indication of distal or total gastrectomy were included in the study. A total of 32 patients were enrolled in this study with 16 in each group, they were divided either into Group I (Hand Sewn) or Group II (stapling). Mean±SD age of Group I was 53.38±8.69 and Group II was 50.88±9.56 (p=0.445). Male patients were predominant than the female with a male: female ratio being 3.57:1. Mean±SD total operating time was 154.38±16.32 minutes and 136.88±17.40 minutes in Group I and Group II respectively (p=0.001). In Group I, 2(12.5%) patients and in Group II, 1(6.3%) patient had duodenal stump leakage which showed no statistically significant difference (p=0.999). Postoperative hospital stay had no statistically significant difference (p=0.923). The surgical cost had a significant difference (p=0.001) which is more in Group II. This study showed there was a significant reduction in total operating time but there was no significant difference in occurring of duodenal stump leakage or postoperative hospital stay. However, use of stapler hastens the surgeon's job and it relieves extra pressure of them.

Electrosurgery Dissection versus Sharp Dissection: Effect on Early Postoperative Wound Complications in Modified Radical Mastectomy

Modified radical mastectomy (MRM) is still the most commonly performed operation for breast cancer, despite the trends toward breast-conserving treatment. Since 1970s, electrosurgery (also known as electrocautery, diathermy) has been a widespread surgical tool to raise flaps and excise the breast specimen in order to perform a bloodless mastectomy. Use of diathermy has been well blamed for wound complications. To prevent undue delay in the adjuvant treatment, it is important to minimize the surgical complications. This quasi experimental study was conducted in the Department of Surgery, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh to evaluate the effects of electrosurgery and sharp dissection on early postoperative wound complications in MRM. 46 patients were included in the study (23 in each group). Data analysis done in SPSS version 23.0 and 'p' value <0.05 considered significant at 95% confidence interval. In Electrosurgery Dissection (ED) group mean duration of drainage was 7.8±1.2 days and in Sharp Dissection (SD) group 6.4±1.0 days (p value 0.000). Mean total drainage in ED group found 1082±287ml and in SD group 693±194ml (p value 0.000). Seroma formation found 7(30.4%) in ED group and 3(13.0%) in SD group (p value 0.004). Wound dehiscence found 5(21.7%) in ED group and 2(8.7%) in SD group (p value 0.013). Flap necrosis rate was 4(17.4%) and 1(4.4%) in ED and SD group respectively (p=0.003). Demographic and clinical variables were similar or differences were not statistically significant in two groups. No difference found in operating time and wound infection rate in two groups. The result of the study showed that, electrocautery dissection caused early postoperative wound complications more than the sharp dissection.

Role of Endoscopic Ultrasound Guided Fine Needle Aspiration in the Diagnosis of Pancreatic Lesions

To evaluate the diagnostic utility of endoscopic ultrasound guided fine needle aspiration (EUS-FNA) of pancreatic lesions, EUS-FNA was carried out on a total of 28 cases at the Department of Surgery, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from June 2015 to August 2016. Clinical impression was compared with the final cytological diagnosis and the percentage of non diagnostic smears was calculated. The lesions were categorized according to cytological report. Out of 28 cases, 3(10.71%) cases were normal, 6 cases (21.43%) were reported as inconclusive while a definite diagnosis was given in 19 cases (67.85%). The mean patient age was 47.82 years. There were 16(57.1%) males and 12(42.9%) females. The most common site biopsied was pancreatic head in 21cases (75%) followed by tail in 5 cases (17.9%) & body in 2(7.1%) cases. The average number of passes made was two. Endoscopic Ultrasound Guided Fine-Needle Aspiration in the diagnosis of pancreatic lesion is a useful procedure.

Bilateral Tubercular Mastitis - Case Reports

Breast tuberculosis is a rare form of tuberculosis. Moreover the disease is often overlooked and misdiagnosed as carcinoma or pyogenic abscess. Reports on breast tuberculosis have been few; reported incidence of breast tuberculosis amongst the total number of mammary conditions varies between 0.1 and 4 percent. Bilateral involvement is still more uncommon (3%). Here we report 3 cases of adult female ranging from 27 to 35 years who presented with 1 to 4 months history of firm lumps in both breasts and no axillary lymphadenopathy. Fine needle aspiration cytology (FNAC) of breast lump in all 3 cases were done but in 1 case showed evidence of tubercular mastitis and other 2 cases findings were inconclusive. Subsequent Excisional Biopsy of those 2 cases showed features of tuberculosis. All 3 were prescribed with four drug anti-tubercular treatments continued for 12 months in 2 cases and 9 months in other case depending upon their response. The lumps disappeared and ulcer healed after anti-tubercular treatment.

Primary malignant melanoma of the penis with secondary to adrenal

Primary malignant melanoma of penis with secondaries to the adrenal gland is rare. Here we report a case of malignant melanoma of penis in a 60 years old man who presented with intermittent gross, episodic haematuria of 11 months duration and a hard indurated pigmented fungating lesion over the glans penis. Following an initial tissue biopsy from the penile growth which revealed malignant melanoma the patient underwent partial Panectomy. Few days after recovery the patient underwent laparotomy and incisional biopsy from adrenal mass revealed metastatic malignant melanoma histopathologically.

Effects of nebulized budesonide as an adjunct to standard treatment of asthma exacerbations: a randomized, double-blind, placebo-controlled trial

This study was done to determine the effects and outcome of inhaled budesonide in addition to standard management of asthma exacerbations in pediatric age groups. A randomized, double-blind, placebo controlled trial was done in a tertiary care urban hospital. Sixty six children aged 5 to 15 years with moderate to severe asthma exacerbations were eligible. All patients received a single dose of prednisolone 1mg/kg orally as first dose of systemic corticosteroids and then salbutamol (0.15mg/kg) and ipratropium bromide (500mcg) was nebulized every 20 minutes for 3 doses and then hourly for 2 hours as a part of standard treatment of asthma exacerbations. The intervention was 2mg (4mL) of budesonide or 4mL of normal saline which was nebulized immediately after the 1st dose of nebulized salbutamol and ipratropium bromide. The baseline characteristics of the budesonide group (n=33) and placebo group (n=33) were similar, but at 1 hour, 2 hour and 3 hour PEFR, respiratory rate, pulse rate, SaO2 and asthma score were significantly improved in the budesonide group compared to placebo group (p<0.01). The positive immediate effect of nebulized budesonide added to standard treatment of asthma exacerbations is an encouraging finding for further investigations of its routine use in the treatment of asthma exacerbations in children.

Pulmonary alveolar microlithiasis (PAM) in a child

A 4 year 7 month-old girl of consanguineous parents presented with only fever for 25 days but no cough or respiratory distress. Ches x-ray showed bilateral diffuse nodulo-striate opacities in both lungs. Investigations for any infection were negative including tuberculosis. Thoracoscopic biopsy showed alveolar microliths on histopathology suggesting the diagnosis of pulmonary alveolar microlithiasis (PAM).

Association of positive thyroid auto antibodies with thyroid carcinoma

The association between thyroid autoimmunity and thyroid cancer was carried out in a series of solitary thyroid nodules submitted to fine-needle aspiration cytology and subsequent histopathology. US guided FNACs were obtained from 295 unselected consecutive patients with single thyroid nodules and positive (98) or negative (197) serum anti-thyroid antibody. Cytological results were classified in three classes of increased risk of malignancy: low risk (class II); indeterminate risk (class III); and suspect or malignant (class IV). A higher prevalence of class III (29.6%, p<0.05) and class IV (17.34%, p<0.05) and lower prevalence of class II (52.06%, p<0.01) were found in ATA+ nodules respectively. By multivariate logistic regression analysis ATA+ conferred a significant risk (odds ratio: 1.97 & 95% confidence interval: 0.97-3.97) for class IV cytology independently for age and sex. In 53 patients where thyroidectomy was carried out, thyroid cancer was found in (86.66%) patients with class IV nodules, in (19.4%) of class III nodules (all ATA-) and in none of 7 class II nodules. Histologically proven thyroid cancer (mostly papillary) was then observed in a higher proportion (13.2%) of ATA+, when compared with ATA- nodules (8.1%, p>0.01), but the significance of this finding is limited by the low number of class II nodules operated on. The presence of ATA+ confers an increased risk of suspicious or malignant cytology in solitary thyroid nodules.

Genotypes of rotavirus diarrhoea in a children hospital of Bangladesh

Globally, rotaviruses are the single most important etiologic agents of severe childhood dehydrating diarrhea that accounts for more than 125 million of cases, 25-55% of all hospital admissions for diarrhea and ≈600,000 deaths every year. In Bangladesh, while overall diarrhea related deaths are declining, the proportion of diarrhea deaths due to rotavirus is increasing. This study was aimed at estimating the burden of rotavirus diarrhea and isolating the genotypes of rotavirus in a children hospital of Bangladesh; thereby endorsing a logical search for an appropriate rotavirus vaccine. This cross sectional study was carried out in the Institute of Child and Mother Health, Matuail, Dhaka, Bangladesh during 2006-2007. Children aged between one month and five years suffering form diarrhea were enrolled in the study. Stool samples were analyzed by ELISA for rotavirus antigen. The rotavirus-positive samples were further analyzed for genotype determination. Among 656 stool samples, 39.5% samples were positive for rotavirus antigen. The mean age of the children studied was 12±9.9 months; the peak being in the second half of infancy. G2 was identified as the most dominant genotype (45.5%) followed by G1 (24.8%), G12 (9.6%), G9 (8.5%) and G4 (2.1%) genotypes. Since G2 were found to be the predominant circulating rotavirus strain in this study and some other studies in Bangladesh, the recommended vaccine for prevention of rotavirus infection in Bangladesh should cover this strain to have maximum effectiveness.

Role of intraoperative flexible Choledochoscopy in calculous biliary tract disease

Ninety six percent of patients with overlooked bile duct stones required surgery within 5 years of cholecystectomy, every effort should be made to keep the incidence of retained stones minimum. The facilities of pre-operative ERCP are not always available. Examination of the bile ducts under direct vision with a choledochoscope seems a certain method of ensuring that there are no residual stone. A total of 26 patients were evaluated between the periods of 2004 to 2005. Age of the patients ranged from 20 to 70 years. The mean age is about 45.88 years approximately. Six (23.07%) cases had previous history of cholecystectomy. Peroperatively 14(53.84%) cases had only choledocholithiasis, 6(23.07%) cases had cholelithiasis with choledocholithiasis, 4(15.38%) cases had choledocholithiasis with hepatolithiasis and 2(7.69%) cases had Mirrizi's type II with choledocholithiasis. After Choledochoscopy, 22(84.61%) cases had complete blind clearance, 4(15.38%) cases had incomplete blind clearance. Twenty two (84.61%) cases did not require any Choledochoscopy guided stone extraction. Four (15.38%) cases required Choledochoscopy guided Dormia basket extraction. Twenty two (84.61%) cases have undergone T tube drainage, 4(15.38%) cases undergone Roux-en-Y hepaticojejunostomy who had associated hepatolithiasis. In this series percentage of stone overlooked by instrumental exploration was 15.38 & percentage of residual stone in this study was 0%.

A 30 year old female with lower abdominal lump

A female of 30 years of age, hailing from Narayangonj, Dhaka got admitted herself into Dhaka medical College & Hospital on 25.10.08 with the complaints of a lump in the lower abdomen for 1 year and pain in the lower abdomen for the same duration. Local examination reveals a lump in the lower abdomen which is intra abdominal, 10cm × 12cm in size. CT scan of Abdomen reveals a solid mass measuring (12 × 9 × 8.5) cm is seen in left side of abdominal cavity extending up to pelvic cavity. FNAC of abdominal lump shows sheets of mesothelial cells and few small clusters of regular epithelial like cells. Laparotomy was done on 27.11.08 under G/A & reveals a solid mass measuring about 10 × 8cm size & was well encapsulated, adherent with omentum found in the lower abdomen. Few mesenteric lymph nodes were enlarged. The mass was gently separated from the omentum ensuring adequate haemostasis. Post-operative period was uneventful. Histopathology report shows neoplasm composed of plump of fibroblasts arranged in broad sweeping fascicles and infiltrate into adjacent tissue consistent with fibromatosis. The patient was discharged with advice on 10th post operative day.

Role of immunochromatographic test for rapid diagnosis of malaria

The study was conducted to compare among the different diagnostic procedures for malaria in the department of Microbiology, Mymensingh Medical College, Mymensingh during the period from July 2005 to June 2006. In this study a total of 98 malaria patients were included as cases. Another 30 age and sex matched healthy people were included as controls. Blood sample from each of the case and control was collected and examined for malarial parasite by microscopic examination of peripheral blood film. Subsequently antigen and antibody were detected by immuno-chromatographic test (ICT). Out of 98 clinically suspected cases 59(60.20%) were positive for malarial parasite by microscopic examination of peripheral blood film, 57(58.16%) were positive by ICT for antigen and 58(59.19%) were positive by ICT for antibody. Sensitivity and specificity of ICT for antigen were 93.22% and 94.87% respectively. For antibody, sensitivity and specificity were 89.83% and 87.17% respectively. From this study, sensitivity and specificity of ICT for malaria was found quite satisfactory, so it is suggested that ICT for malaria could be an alternative to peripheral blood film for the diagnosis of malaria where parasite could not be detected in peripheral blood film.

Zero-order release of aspirin, theophylline and atenolol in water from novel methylcellulose glutarate matrix tablets

A novel hydrocolloidal polymer, methylcellulose glutarate (MC-GA), was prepared by esterifying methylcellulose with glutaric anhydride. The formation of ester was confirmed by FTIR and NMR spectroscopy, DSC and elemental analysis. The physicochemical properties such as, rate of swelling in water, viscosity and hygroscopicity of MC-GA were determined and compared with those of methycellulose A (MC). Aspirin, theophylline and atenolol tablets were compacted on a Carver press using the wet granulation method. Each tablet contained: 200 mg active, 80 mg anhydrous lactose, 8 mg povidone, 4 mg magnesium stearate, 4 mg talc, 50mg MC or MC-GA (drug-to-polymer ratio, 4:1). Contrary to the first-order release profile of all the drugs from the MC matrix tablets, a zero-order release was obtained from the MC-GA matrix tablets in water.

The treatment of osteochondral lesions using a combination of autologous chondrocyte implantation and autograft

In this study a combination of autologous chondrocyte implantation (ACI) and the osteochondral autograft transfer system (OATS) was used and evaluated as a treatment option for the repair of large areas of degenerative articular cartilage. We present the results at three years post-operatively. Osteochondral cores were used to restore the contour of articular cartilage in 13 patients with large lesions of the lateral femoral condyle (n = 5), medial femoral condyle (n = 7) and patella (n = 1). Autologous cultured chondrocytes were injected underneath a periosteal patch covering the cores. After one year, the patients had a significant improvement in their symptoms and after three years this level of improvement was maintained in ten of the 13 patients. Arthroscopic examination revealed that the osteochondral cores became well integrated with the surrounding cartilage. We conclude that the hybrid ACI/OATS technique provides a promising surgical approach for the treatment of patients with large degenerative osteochondral defects.

Enhancement of anti-cancer immunity by a lipoteichoic-acid-related molecule isolated from a penicillin-killed group A Streptococcus

We isolated the lipoteichoic-acid-related molecule (OK-PSA) from OK-432, a streptococcal preparation, by affinity chromatography on CNBr-activated Sepharose-4B-bound monoclonal antibody TS-2, which neutralizes the interferon (IFN)-gamma-inducing activity of OK-432. We have previously reported that OK-PSA is a potent inducer of Th1-type cytokines in human peripheral blood mononuclear cells in vitro. In this study, we conducted an animal experiment to examine whether OK-PSA exhibits an anti-tumor effect in vivo by acting as a Th1 inducer in syngeneic Meth-A tumor-bearing BALB/c mice, in which the Th2 response is genetically dominant. It was found that OK-PSA induced Th1-type cytokines [IFN-gamma, tumor necrosis factor-alpha, interleukin (IL)-2, IL-12 and IL-18] in BALB/c mice bearing Meth-A tumor and caused a marked anti-tumor effect. Although it was suggested by an in vitro study. using spleen cells derived from the animals, that IL-18 plays the greatest role in the induction of the Th1-dominant state and tumor cell killing induced by OK-PSA, the in vivo experiments demonstrated that both IL-12 and IL-18 are essential in the anti-tumor effect exhibited by OK-PSA. These findings strongly suggest that OK-PSA is a major effector molecule of OK-432 and may be a useful immunotherapeutic agent, as a potent Th1 inducer, for cancer patients with a Th2-dominant state.

Molecular epidemiology of C9 deficiency heterozygotes with an Arg95Stop mutation of the C9 gene in Japan

Deficiency of the ninth component of human complement (C9) is the most common complement deficiency in Japan, with an incidence of approximately one homozygote in 1000, but is very rare in other countries. Genetic analyses of Japanese C9 deficiency have shown that a C-to-T transition leading to TGA stop codon for Arg95 in exon 4 of the C9 gene (Arg95Stop) is common in Japanese C9 deficiency. To determine the prevalence of heterozygous carriers of the Arg95Stop mutation in a Japanese population, we collected DNA samples from 300 individuals in two of the four main islands of Japan. Heterozygote detection was performed with an allele-specific polymerase chain reaction (PCR) system designed to detect exclusively only one of the normal and mutant alleles, followed by confirmation with PCR/single-strand conformation polymorphism (SSCP) analysis and direct sequencing. Twenty individuals were heterozygous for the Arg95Stop mutation. None was homozygous. The prevalence of carriers of the Arg95Stop mutation was 6.7% (20/300). An estimated frequency (0.12%) of complete C9 deficiency due to homozygous Arg95Stop mutation was consistent with frequencies determined by serological studies.

A putative vacuolar cargo receptor partially colocalizes with AtPEP12p on a prevacuolar compartment in Arabidopsis roots

Targeting of protein cargo to the vacuole/lysosome is a multistep process that appears to have conserved features between mammalian, yeast, and plant cells. In each case, some soluble vacuolar/lysosomal proteins are believed to be bound by transmembrane cargo receptors in the trans-Golgi network (TGN) that redirect these proteins into clathrin-coated vesicles. These vesicles then appear to be transported to the prevacuole/endosome by a trafficking machinery that requires components identified in other vesicle-targeting steps such as N-ethylmaleimide-sensitive factor (NSF), soluble NSF attachment protein (SNAP), SNAP receptors (SNAREs), rab-type GTPases, and Sec1p homologs. Two likely members of this trafficking machinery have been characterized from Arabidopsis thaliana: AtPEP12p, a t-SNARE that resides on a what we now call a prevacuolar compartment, and AtELP, a protein that shares many common features with mammalian and yeast transmembrane cargo receptors. Here, we have further investigated the intracellular distribution of AtELP. We have found that AtELP is located at the trans-Golgi of Arabidopsis root cells, and that its C terminus can preferentially interact in vitro with the mammalian TGN-specific AP-1 clathrin-adapter complex, suggesting a likely role in clathrin-coated, vesicle-directed trafficking at the TGN. Further, consistent with a role in trafficking of vacuolar cargo, we have found that AtELP partially colocalizes with AtPEP12p on a prevacuolar compartment.

Cloning and subcellular location of an Arabidopsis receptor-like protein that shares common features with protein-sorting receptors of eukaryotic cells

Many receptors involved in clathrin-mediated protein transport through the endocytic and secretory pathways of yeast and animal cells share common features. They are all type I integral membrane proteins containing cysteine-rich lumenal domains and cytoplasmic tails with tyrosine-containing sorting signals. The cysteine-rich domains are thought to be involved in ligand binding, whereas the cytoplasmic tyrosine motifs interact with clathrin-associated adaptor proteins during protein sorting along these pathways. In addition, tyrosine-containing signals are required for the retention and recycling of some of these membrane proteins to the trans-Golgi network. Here we report the characterization of an approximately 80-kD epidermal growth factor receptor-like type I integral membrane protein containing all of these functional motifs from Arabidopsis thaliana (called AtELP for A. thaliana Epidermal growth factor receptor-Like Protein). Biochemical analysis indicates that AtELP is a membrane protein found at high levels in the roots of both monocots and dicots. Subcellular fractionation studies indicate that the AtELP protein is present in two membrane fractions corresponding to a novel, undefined compartment and a fraction enriched in vesicles containing clathrin and its associated adaptor proteins. AtELP may therefore serve as a marker for compartments involved in intracellular protein trafficking in the plant cell.

Influence of jet direction on pulmonary vein flow patterns in severe mitral regurgitation

Pulmonary vein flow patterns measured with transesophageal echocardiography have been used recently to assess the severity of mitral valve regurgitation. This study was designed to determine whether regurgitant jet direction selectively influences the pattern of flow in right and left pulmonary veins. Thirty-seven patients undergoing mitral valve repair or replacement for severe valvular regurgitation were studied intraoperatively with biplane transesophageal echocardiography. Regurgitant jets were classified by color flow mapping as central or wall, with the latter further classified as septal, lateral, anterior, or posterior in the two orthogonal scan planes. Pulmonary vein flow patterns were measured with pulsed wave Doppler ultrasonography and categorized as showing normal, blunted, or reversed systolic flow. Right and left pulmonary vein flow patterns were identical in the majority of patients studied (78%). Eight patients had discordant flow patterns. In seven of eight patients, the more abnormal pattern was seen in the right pulmonary vein, despite the fact that the regurgitant jets were directed centrally in four of these seven patients. Since discordant pulmonary vein flow patterns occurred in 5 of 15 patients (33%) with central jets, but in only 3 of 22 patients (14%) with eccentric wall jets, it is unlikely that mitral regurgitation jet direction per se causes predictable and selective unilateral alteration in pulmonary vein flow patterns.

Flow reversal in the descending aorta: a guide to intraoperative assessment of aortic regurgitation with transesophageal echocardiography

This study assessed the value of biplane transesophageal echocardiographic assessment of diastolic flow reversal in the descending aorta as an alternative to Doppler color flow imaging in determining severity of aortic regurgitation. In 45 patients undergoing cardiac operations, the severity of aortic regurgitation was assessed by semiquantitative grading of the width of the Doppler color flow regurgitant jet relative to the left ventricular outflow tract, and the presence of diastolic flow reversal was assessed with pulsed-wave Doppler measurements at three sites in the descending aorta. In four patients, the diastolic flow reversal method was the only available form of assessment because of inadequate visualization of the left ventricular outflow tract beneath a mitral valve prosthesis. Diastolic flow reversal in the descending aorta was not observed in patients without aortic regurgitation and was always present in patients with severe aortic regurgitation. Aortic valve replacement successfully eliminated descending aortic flow reversal in all 19 patients in whom it was present before valve replacement. Identification of diastolic flow reversal at multiple sites in the descending aorta with biplane transesophageal echocardiography helps to confirm the presence of severe aortic regurgitation and can serve as an alternative method of assessment when visualization of the left ventricular outflow tract is impaired.

Characteristics and applications of birefringent-fiber Kerr-couplers

We consider the effects of the pump power and the interaction length on the efficiency of polarization coupling induced by the optical Kerr effect in high-birefringence fibers. An efficiency of up to 100% is predicted for suitable combinations of the length and the strength of the birefringence grating in the fiber. The device is rapidly tunable, highly selective in wavelength, and independent of any thermal drift in the fiber. Potential applications include real-time tuning in wavelength-division demultiplexers, wavelength selection in optical spectrum analyzers, and band rejection in tunable notch filters.

Phase-matched polarization coupling in high-birefringence fibers through the optical Kerr effect

We describe the use of the optical Kerr effect in a simple and novel way to write a transient polarization coupler in high-birefringence fiber. A conversion efficiency of as much as 0.4% is demonstrated, with a coupling bandwidth of approximately 0.4 nm. The method is fast and independent of any thermal drift. Potential applications include real-time tuning in wavelength-division demultiplexers and wavelength selection in optical spectrum analyzers.

The lipid composition of cattle sebaceous glands: a comparison with skin surface lipid

The lipid composition of isolated sebaceous glands from Ayrshire calves was compared with that of freshly secreted skin surface lipid. The sebaceous gland contained a higher proportion of phospholipid and unesterified fatty acid and a lower proportion of triglyceride; otherwise there was little difference in lipid composition between samples from the gland and the skin surface.