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81.
Many optimization problems in science and engineering are highly nonlinear and thus require sophisticated optimization techniques to solve. Traditional techniques such as gradient-based algorithms are mostly local search methods and often struggle to cope with such challenging optimization problems. Recent trends tend to use nature-inspired optimization algorithms. The standard cuckoo search (CS) is an optimization algorithm based on a single cuckoo species and a single host species. This work extends the standard CS by using the successful features of the cuckoo-host co-evolution with multiple interacting species. The proposed multi-species cuckoo search (MSCS) intends to mimic the co-evolution among multiple cuckoo species that compete for the survival of the fittest. The solution vectors are encoded as position vectors. The proposed algorithm is then validated by 15 benchmark functions as well as five nonlinear, multimodal case studies in practical applications. Simulation results suggest that the proposed algorithm can be effective for finding optimal solutions and all optimal solutions are achievable in the tested cases. The results for the test benchmarks are also compared with those obtained by other methods such as the standard cuckoo search and genetic algorithm. The comparison has demonstrated the efficiency of the present algorithm. Based on numerical experiments and case studies, we can conclude that the proposed algorithm can be more efficient in most cases. Therefore, the proposed approach can be a very effective tool for solving nonlinear global optimization problems.  相似文献   
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Purpose: To describe the clinical features, treatment, and outcomes of conjunctival melanoma in Asian Indians.

Methods: Retrospective study of 42 patients.

Results: The mean age at presentation of conjunctival melanoma was 43 years (median, 45 years; range, 9–78 years). There were 20 (48%) males and 22 (52%) females. Nineteen patients (45%) had a known history of a preexisting pigmented conjunctival lesion. Bulbar conjunctiva (n = 28; 67%) was the most common tumor epicenter, and medial ocular surface quadrant (n = 15; 36%) was more commonly involved. The mean tumor basal diameter was 12 mm (median, 10 mm; range, 4–30 mm), and the mean tumor thickness was 4 mm (median, 2 mm; range, 1–30 mm). Majority of the patients had a pigmented tumor (n = 33; 79%). The tumors arose de novo (n = 17, 41%) or were associated with conjunctival nevus (n = 9; 21%) or primary acquired melanosis (n = 16, 38%). Wide excisional biopsy, adjunctive cryotherapy, and amniotic membrane grafting were performed in 27 (71%) patients, 11 (29%) underwent orbital exenteration, and 4 were lost to follow-up prior to definitive treatment. Over a mean follow-up period of 24 months (median, 9 months; range, <1 to 136 months), four (11%) patients had tumor recurrence, seven (18%) had locoregional lymph node metastasis, and four (11%) developed systemic metastasis and died due to metastatic disease.

Conclusion: Conjunctival melanoma predominantly occurs in middle-aged Asian Indians and is associated with a high rate of systemic metastasis and death.  相似文献   

84.
Polymorphisms in xenobiotic metabolizing genes are associated with altered metabolism of carcinogens in acute leukemia (AL). This study applied two data mining approaches to explore potential interactions among P53 and xenobiotic metabolizing genes in 230 AL patients [131 acute myeloid leukemia (AML) and 99 acute lymphoblastic leukemia (ALL)] and 199 controls. Individually, none of the genotypes showed significant associations with AML risk. However, in ALL the CYP1A12A TC genotype was associated with increased risk (OR = 2.02; 95% CI = 1.14–3.58; P = 0.01), whereas the GSTM1 null genotype imparted reduced risk (OR = 0.55; 95% CI = 0.31–0.96; P = 0.03). In classification and regression tree analysis, combinations of GSTM1 present, CYP1A12C AA or GG, EPHX1 exon3 TC, and EPHX1 exon4 AA or GG genotype strongly enhanced the risk of AML (OR = 5.89; 95% CI = 1.40–26.62; P = 0.01). In ALL, combinations of CYP1A12A TT, P53 GG or CC and GSTP1 AG genotypes conferred the highest risk (OR = 4.19; 95% CI = 1.45–12.25; P = 0.004). In multifactor dimensionality reduction analysis, a four locus model (GSTP1, P53, EPHX1 exon3, and CYP1A12A) was the best predictor model for ALL risk. The association between this model and ALL risk remained true even at low prior probabilities of 0.01% (false positive report probability = 0.05). Interaction entropy interpretations of the best model of ALL revealed that two‐way interactions were mostly synergistic. These results suggest that high order gene–gene interactions play an important role in AL risk. Environ. Mol. Mutagen., 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
85.

Context

Quality of life (QoL) is increasingly recognized as an important outcome of cancer treatment. Previous studies have examined clinical predictors of QoL, but with the increasing prevalence of wearable sensors that monitor sleep and activity patterns, further investigation into whether these behaviors are predictive of post-treatment QoL is now feasible. Among patients receiving aggressive cancer treatment such as hematopoietic cell transplantation (HCT), analysis of circadian rhythms (24-hour patterns of sleep and activity) via wearable sensors is limited.

Objective

To evaluate the relationship between overall QoL and circadian rhythms in patients receiving allogeneic HCT.

Methods

Patients wore an ActiGraph GT3X (Pensacola, FL) activity monitor for at least 72 hours before the initiation of conditioning chemotherapy and transplantation and completed a QoL (Functional Assessment of Cancer Therapy-General [FACT-G]) assessment. QoL assessments were also completed 1, 3, and 6 months after HCT.

Results

Patients (n = 45, M age = 55) were mostly male (66%) with a total FACT-G score of 80.96 (SD = 16.05) before HCT. Mixed models revealed robust cross-sectional associations between overall QoL and multiple circadian rhythmicity parameters, including durations of high physical activity, overall circadian rhythmicity, and earlier starts of daily activity (P's < .01). Recovery of QoL after transplant was predicted by longer pre-transplant durations of high physical activity (P = .04) and earlier evening retirement (P = .04).

Conclusion

Our findings suggest that wearable sensor information is a promising method of predicting recovery of QoL after HCT. Additional studies are needed to confirm these findings in a larger sample.  相似文献   
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Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - The results show that the orb-weaver spiders, Neoscona theisi and Cyrtophora citricola, occurred in both...  相似文献   
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Visceral leishmaniasis (VL) remains a major health problem in old world, and India accounts for half of the world burden. The widespread emergence of resistance to standard drug in India poses a major obstacle in the control of leishmaniasis. Post-Kala-Azar dermal leishmaniasis (PKDL) is considered as main source of drug resistance. Experimental data indicate that resistance against newer drugs is also imminent. Therefore, in vitro studies were carried out to test minimum parasiticidal concentration of five conventional and newly introduced anti-leishmanial drugs against 20 field isolates of Leishmania donovani obtained from visceral and post-Kala-Azar dermal leishmaniasis patients of India. Study revealed wide range of variation in minimum inhibitory concentration of sodium antimony gluconate (SAG). PKDL isolates displayed significantly lower susceptibility to SAG and miltefosine than VL isolates with P value of 0.0006 and 0.0243, respectively. All clinical isolates had higher IC50 value for paromomycin and miltefosine as compared to reference strain indicating their vulnerability to develop unresponsiveness. However, isolates were uniformly susceptible to pentamidine and amphotericin B. The results of gene expression analysis of AQP1 were largely in agreement with phenotypic drug sensitivity results. Interestingly, significant down-regulation of AQP1 was observed in PKDL isolates as compared to VL isolates indicating their increased propensity for drug unresponsiveness. However, no significant difference in mRNA expression of LdMT and LdRos3 gene was found for two groups. The present study unravels valuable baseline scientific data showing variation in the drug susceptibility pattern in the L. donovani isolates. The information might have impact on the management and control of Indian visceral leishmaniasis.  相似文献   
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