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Including all available data when developing equations to relate midinfrared spectra to a phenotype may be suboptimal for poorly represented spectra. Here, an alternative local changepoint approach was developed to predict six milk technological traits from midinfrared spectra. Neighbours were objectively identified for each predictand as those most similar to the predictand using the Mahalanobis distances between the spectral principal components, and subsequently used in partial least square regression (PLSR) analyses. The performance of the local changepoint approach was compared to that of PLSR using all spectra (global PLSR) and another LOCAL approach, whereby a fixed number of neighbours was used in the prediction according to the correlation between the predictand and the available spectra. Global PLSR had the lowest RMSEV for five traits. The local changepoint approach had the lowest RMSEV for one trait; however, it outperformed the LOCAL approach for four traits. When the 5% of the spectra with the greatest Mahalanobis distance from the centre of the global principal component space were analysed, the local changepoint approach outperformed the global PLSR and the LOCAL approach in two and five traits, respectively. The objective selection of neighbours improved the prediction performance compared to utilising a fixed number of neighbours; however, it generally did not outperform the global PLSR.

Multivariate time-dependent data, where multiple features are observed over time for a set of individuals, are increasingly widespread in many application domains. To model these data, we need to account for relations among both time instants and variables and, at the same time, for subject heterogeneity. We propose a new co-clustering methodology for grouping individuals and variables simultaneously, designed to handle both functional and longitudinal data. Our approach borrows some concepts from the curve registration framework by embedding the shape invariant model in the latent block model , estimated via a suitable modification of the SEM-Gibbs algorithm. The resulting procedure allows for several user-defined specifications of the notion of cluster that can be chosen on substantive grounds and provides parsimonious summaries of complex time-dependent data by partitioning data matrices into homogeneous blocks. Along with the explicit modelling of time evolution, these aspects allow for an easy interpretation of the clusters, from which also low-dimensional settings may benefit., (© The Author(s) 2021.)

Study Objective: To verify the value, feasibility, and reliability of transvaginal hydrolaparoscopic ovarian drilling using the bipolar VersaPoint system to treat clomiphene-resistant, anovulatory women with polycystic ovary syndrome., Design: Prospective clinical study (Canadian Task Force classification II-2)., Setting: University teaching hospital., Patients: Twenty-eight women., Intervention: Transvaginal hydrolaparoscopic ovarian drilling using the bipolar VersaPoint spring electrode., Measurements and Main Results: After the surgical procedure, ovulation occurred spontaneously in 66.7% of women. Thirteen pregnancies occurred; eight were spontaneous, and four were achieved after induction of ovulation with clomiphene citrate and one after stimulation with gonadotropins. In 21 women whose infertility was due exclusively to anovulation, the cumulative pregnancy rate was 38% at 3 months and 76% at 6 months. No ovarian hyperstimulation or abortion occurred. The single complication was bleeding from an ovary that required conversion to laparoscopy., Conclusion: Transvaginal hydrolaparoscopic ovarian drilling with the bipolar VersaPoint system is a useful therapeutic option in these women.

Objective: To verify the usefulness and reliability of transvaginal hydrolaparoscopy (THL) as a screening tool for evaluating infertility in women in comparison with conventional diagnostic laparoscopy., Study Design: Sixty consecutive women with unexplained primary infertility were prospectively enrolled into the study. After examination of the whole pelvic cavity, tubal patency was evaluated and the uterine cavity studied by hysteroscopy. Immediately after THL, conventional laparoscopy was performed. Main outcome measures were the success rate of accessing the pouch of Douglas, rate of complete examinations, rate of complications and accuracy of THL in comparison with laparoscopy., Results: Success rate of accessing the pouch of Douglas and performing THL was 93.3%. The rate of complete evaluation of all the pelvic structures was 76.8%. In studying tubal pathology, 77.8% agreement was found between the two techniques. Diagnosis of endometriosis was correct in 55.5% of patients. Overall, THL results correlated closely with conventional laparoscopic results in 92.86%, but the diagnostic accuracy of THL was 100% in cases of complete pelvic evaluation., Conclusion: THL is a feasible, reliable and safe procedure and can be considered an alternative procedure for evaluating infertility in women. In cases of incomplete pelvic evaluation or abnormal findings, conventional laparoscopy is indicated as the second step in the evaluation.