A predator-prey mathematical model with competitive interaction amongst two species

A mathematical model is constructed to study the effect of predation on two competing species in which one of the competing species is a prey to the predator whilst the other species is not under predation.  We assume that all species can move by diffusion and study the spatial structure of the species and obtained conditions for the existence and stability of equilibrium solutions. The results indicate the possibility of a stable coexistence of the three interacting species in form of stable oscillations under the reflecting boundary conditions.  Numerical simulations supported our theoretical predictions.   By utilizing Liapunov-like functions and differential inequalities we were able to establish that the system is dissipative

Effect of Photoperiod on the Germination and Seedling Development of Some (Acha) Digitaria Species

A glass house study was conducted at the Botanical garden, University of Jos, Jos Nigeria to study the effects of photoperiod on germination and seedling development of three Digitaria species (D. exilis, D. barbinodis, and D. iburua) using the Completely Randomized Design (CRD).The three species were subjected to photoperiods of 6, 8, 10, and 12hrs for 21 days. Results show that D. iburua had 30% germination while D. exilis and D. barbinodis had 80% germinatio

Molecular Characterization and Patient Outcome of Melanoma Nodal Metastases and an Unknown Primary Site

Background Melanoma of unknown primary site (MUP) is not a completely understood entity with nodal metastases as the most common first clinical manifestation. The aim of this multicentric study was to assess frequency and type of oncogenic BRAF/NRAS/KIT mutations in MUP with clinically detected nodal metastases in relation to clinicopathologic features and outcome. Materials and Methods We analyzed series of 103 MUP patients (period: 1992-2010) after therapeutic lymphadenectomy (LND): 40 axillary, 47 groin, 16 cervical, none treated with BRAF inhibitors. We performed molecular characterization of BRAF/NRAS/KIT mutational status in nodal metastases using direct sequencing of respective coding sequences. Median follow-up time was 53 months. Results BRAF mutations were detected in 55 cases (53 %) (51 V600E, 93 %; 4 others, 7 %), and mutually exclusive NRAS mutations were found in 14 cases (14 %) (7 p.Q61R, 4 p.Q61K, 2 p.Q61H, 1 p.Q13R). We have not detected any mutations in KIT. The 5-year overall survival (OS) was 34 %; median was 24 months. We have not found significant correlation between mutational status (BRAF/NRAS) and OS; however, for BRAF or NRAS mutated melanomas we observed significantly shorter disease-free survival (DFS) when compared with wild-type melanoma patients (p = .04; 5-year DFS, 18 vs 19 vs 31 %, respectively). The most important factor influencing OS was number of metastatic lymph nodes >1 (p = .03). Conclusions Our large study on molecular characterization of MUP with nodal metastases showed that MUPs had molecular features similar to sporadic non-chronic-sun-damaged melanomas. BRAF/NRAS mutational status had negative impact on DFS in this group of patients. These observations might have potential implication for molecular-targeted therapy in MUPs

Enzyme‐assisted aqueous extraction of Kalahari melon seed oil: optimization using response surface methodology

Enzymatic extraction of oil from Kalahari melon seeds was investigated and evaluated by response surface methodology (RSM). Two commercial protease enzyme products were used separately: Neutrase® 0.8 L and Flavourzyme® 1000 L from Novozymes (Bagsvaerd, Denmark). RSM was applied to model and optimize the reaction conditions namely concentration of enzyme (20–50 g kg−1 of seed mass), initial pH of mixture (pH 5–9), incubation temperature (40–60 °C), and incubation time (12–36 h). Well fitting models were successfully established for both enzymes: Neutrase 0.8 L (R 2 = 0.9410) and Flavourzyme 1000 L (R 2 = 0.9574) through multiple linear regressions with backward elimination. Incubation time was the most significant reaction factor on oil yield for both enzymes. The optimal conditions for Neutrase 0.8 L were: an enzyme concentration of 25 g kg−1, an initial pH of 7, a temperature at 58 °C and an incubation time of 31 h with constant shaking at 100 rpm. Centrifuging the mixture at 8,000g for 20 min separated the oil with a recovery of 68.58 ± 3.39%. The optimal conditions for Flavourzyme 1000 L were enzyme concentration of 21 g kg−1, initial pH of 6, temperature at 50 °C and incubation time of 36 h. These optimum conditions yielded a 71.55 ± 1.28% oil recovery

Culturally adapted psychological intervention for treating maternal depression in British mothers of African and Caribbean origin: a randomized controlled feasibility trial

Background: Women are likely to suffer from maternal depression due to childbirth difficulties and parenting responsibilities, leading to long-term negative consequences on their children and families. British mothers of African/Caribbean origin uptake of mental healthcare is low due to the lack of access to culturally appropriate care. Methods: A mixed-methods randomized controlled feasibility trial was adopted to test the appropriateness and acceptability of Learning Through Play plus Culturally adapted Cognitive Behaviour Therapy (LTP+CaCBT) for treating maternal depression compared with Psychoeducation (PE). Mothers (N = 26) aged 20–55 were screened for depression using the Patient Health Questionnaire (PHQ-9). Those who scored >5 on PHQ-9 were further interviewed using the Revised Clinical Interview Schedule to confirm the diagnosis and randomized into LTP+CaCBT (n = 13) or PE (n = 13) groups. Assessments were taken at baseline, end of the intervention at 3- and 6-months post-randomization. N = 2 focus groups (LTP+CaCBT, n = 12; PE, n = 7) and N = 8 individual interviews were conducted (LTP+CaCBT, n = 4; PE, n = 4). Results: The LTP+CaCBT group showed higher acceptability, feasibility and satisfaction levels than the PE group. Participants experienced the intervention as beneficial to their parenting skills with reduced depression and anxiety in the LTP+CaCBT compared to the PE group. Conclusions: This is the first feasibility trial of an integrated online parenting intervention for British African and Caribbean mothers. The results indicated that culturally adapted LTP+CaCBT is acceptable and feasible. There is a need to study the clinical and cost-effectiveness of LTP+CaCBT in an appropriately powered randomized control trial and include the child's outcomes

Familial adenomatous polyposis

Familial adenomatous polyposis (FAP) is characterized by the development of many tens to thousands of adenomas in the rectum and colon during the second decade of life. FAP has an incidence at birth of about 1/8,300, it manifests equally in both sexes, and accounts for less than 1% of colorectal cancer (CRC) cases. In the European Union, prevalence has been estimated at 1/11,300-37,600. Most patients are asymptomatic for years until the adenomas are large and numerous, and cause rectal bleeding or even anemia, or cancer develops. Generally, cancers start to develop a decade after the appearance of the polyps. Nonspecific symptoms may include constipation or diarrhea, abdominal pain, palpable abdominal masses and weight loss. FAP may present with some extraintestinal manifestations such as osteomas, dental abnormalities (unerupted teeth, congenital absence of one or more teeth, supernumerary teeth, dentigerous cysts and odontomas), congenital hypertrophy of the retinal pigment epithelium (CHRPE), desmoid tumors, and extracolonic cancers (thyroid, liver, bile ducts and central nervous system). A less aggressive variant of FAP, attenuated FAP (AFAP), is characterized by fewer colorectal adenomatous polyps (usually 10 to 100), later age of adenoma appearance and a lower cancer risk. Some lesions (skull and mandible osteomas, dental abnormalities, and fibromas on the scalp, shoulders, arms and back) are indicative of the Gardner variant of FAP. Classic FAP is inherited in an autosomal dominant manner and results from a germline mutation in the adenomatous polyposis (APC) gene. Most patients (~70%) have a family history of colorectal polyps and cancer. In a subset of individuals, a MUTYH mutation causes a recessively inherited polyposis condition, MUTYH-associated polyposis (MAP), which is characterized by a slightly increased risk of developing CRC and polyps/adenomas in both the upper and lower gastrointestinal tract. Diagnosis is based on a suggestive family history, clinical findings, and large bowel endoscopy or full colonoscopy. Whenever possible, the clinical diagnosis should be confirmed by genetic testing. When the APC mutation in the family has been identified, genetic testing of all first-degree relatives should be performed. Presymptomatic and prenatal (amniocentesis and chorionic villous sampling), and even preimplantation genetic testing is possible. Referral to a geneticist or genetic counselor is mandatory. Differential diagnoses include other disorders causing multiple polyps (such as Peutz-Jeghers syndrome, familial juvenile polyps or hyperplastic polyposis, hereditary mixed polyposis syndromes, and Lynch syndrome). Cancer prevention and maintaining a good quality of life are the main goals of management and regular and systematic follow-up and supportive care should be offered to all patients. By the late teens or early twenties, colorectal cancer prophylactic surgery is advocated. The recommended alternatives are total proctocolectomy and ileoanal pouch or ileorectal anastomosis for AFAP. Duodenal cancer and desmoids are the two main causes of mortality after total colectomy, they need to be identified early and treated. Upper endoscopy is necessary for surveillance to reduce the risk of ampullary and duodenal cancer. Patients with progressive tumors and unresectable disease may respond or stabilize with a combination of cytotoxic chemotherapy and surgery (when possible to perform). Adjunctive therapy with celecoxib has been approved by the US Food and Drug Administration and the European Medicines Agency in patients with FAP. Individuals with FAP carry a 100% risk of CRC; however, this risk is reduced significantly when patients enter a screening-treatment program