Single Item Lot Sizing Problem for a Warm/Cold Process with Immediate Lost Sales

Cataloged from PDF version of article.We consider the dynamic lot-sizing problem with finite capacity and possible lost sales for a process that could be kept warm at a unit variable cost for the next period t + 1 only if more than a threshold value Qt has been produced and would be cold, otherwise. Production with a cold process incurs a fixed positive setup cost, Kt and setup time, St, which may be positive. Setup costs and times for a warm process are negligible. We develop a dynamic programming formulation of the problem, establish theoretical results on the structure of the optimal production plan in the presence of zero and positive setup times with Wagner–Whitin-type cost structures. We also show that the solution to the dynamic lot-sizing problem with lost sales are generated from the full commitment production series improved via lost sales decisions in the presence of a warm/cold process. 2006 Elsevier B.V. All rights reserved

Impact of varicocele repair on semen parameters in infertile men: A systematic review and meta-analysis

Purpose: Despite the significant role of varicocele in the pathogenesis of male infertility, the impact of varicocele repair (VR) on conventional semen parameters remains controversial. Only a few systematic reviews and meta-analyses (SRMAs) have evaluated the impact of VR on sperm concentration, total motility, and progressive motility, mostly using a before-after analytic approach. No SRMA to date has evaluated the change in conventional semen parameters after VR compared to untreated controls. This study aimed to evaluate the effect of VR on conventional semen parameters in infertile patients with clinical varicocele compared to untreated controls. Materials and Methods: A literature search was performed using Scopus, PubMed, Embase, and Cochrane databases following the Population Intervention Comparison Outcome (PICOS) model (Population: infertile patients with clinical varicocele; Intervention: VR [any technique]; Comparison: infertile patients with clinical varicocele that were untreated; Outcome: sperm concentration, sperm total count, progressive sperm motility, total sperm motility, sperm morphology, and semen volume; Study type: randomized controlled trials and observational studies). Results: A total of 1,632 abstracts were initially assessed for eligibility. Sixteen studies were finally included with a total of 2,420 infertile men with clinical varicocele (1,424 patients treated with VR vs. 996 untreated controls). The analysis showed significantly improved post-operative semen parameters in patients compared to controls with regards to sperm concentration (standardized mean difference [SMD] 1.739; 95% CI 1.129 to 2.349; p<0.001; I2=97.6%), total sperm count (SMD 1.894; 95% CI 0.566 to 3.222; p<0.05; I2=97.8%), progressive sperm motility (SMD 3.301; 95% CI 2.164 to 4.437; p<0.01; I2=98.5%), total sperm motility (SMD 0.887; 95% CI 0.036 to 1.738; p=0.04; I2=97.3%) and normal sperm morphology (SMD 1.673; 95% CI 0.876 to 2.470; p<0.05; I2=98.5%). All the outcomes showed a high inter-study heterogeneity, but the sensitivity analysis showed that no study was sensitive enough to change these results. Publication bias was present only in the analysis of the sperm concentration and progressive motility. No significant difference was found for the semen volume (SMD 0.313; 95% CI -0.242 to 0.868; I2=89.7%). Conclusions: This study provides a high level of evidence in favor of a positive effect of VR to improve conventional semen parameters in infertile men with clinical varicocele. To the best of our knowledge, this is the first SRMA to compare changes in conventional semen parameters after VR with changes in parameters of a control group over the same period. This is in contrast to other SRMAs which have compared semen parameters before and after VR, without reference to a control group. Our findings strengthen the available evidence and have a potential to upgrade professional societies’ practice recommendations favoring VR to improve conventional semen parameters in infertile men

Impact of Varicocele Repair on Semen Parameters in Infertile Men: A Systematic Review and Meta-Analysis

Purpose:Despite the significant role of varicocele in the pathogenesis of male infertility, the impact of varicocele repair (VR) on conventional semen parameters remains controversial. Only a few systematic reviews and meta-analyses (SRMAs) have evaluated the impact of VR on sperm concentration, total motility, and progressive motility, mostly using a before-after analytic approach. No SRMA to date has evaluated the change in conventional semen parameters after VR compared to untreated controls. This study aimed to evaluate the effect of VR on conventional semen parameters in infertile patients with clinical varicocele compared to untreated controls.Materials and Methods:A literature search was performed using Scopus, PubMed, Embase, and Cochrane databases following the Population Intervention Comparison Outcome (PICOS) model (Population: infertile patients with clinical varicocele; Intervention: VR [any technique]; Comparison: infertile patients with clinical varicocele that were untreated; Outcome: sperm concentration, sperm total count, progressive sperm motility, total sperm motility, sperm morphology, and semen volume; Study type: randomized controlled trials and observational studies).Results:A total of 1,632 abstracts were initially assessed for eligibility. Sixteen studies were finally included with a total of 2,420 infertile men with clinical varicocele (1,424 patients treated with VR vs. 996 untreated controls). The analysis showed significantly improved post-operative semen parameters in patients compared to controls with regards to sperm concentration (standardized mean difference [SMD] 1.739; 95% CI 1.129 to 2.349; pConclusions:This study provides a high level of evidence in favor of a positive effect of VR to improve conventional semen parameters in infertile men with clinical varicocele. To the best of our knowledge, this is the first SRMA to compare changes in conventional semen parameters after VR with changes in parameters of a control group over the same period. This is in contrast to other SRMAs which have compared semen parameters before and after VR, without reference to a control group. Our findings strengthen the available evidence and have a potential to upgrade professional societies' practice recommendations favoring VR to improve conventional semen parameters in infertile men.</p

ÇOCUK ÜROLOJİSİNDE 4-18 YAŞ ARASI YAPILAN CERRAHİ TEDAVİNİN YAŞAM KALİTESİ VE PSİKOLOJİK İYİLİK HALİ İLE İLİŞKİSİ

Most of the studies conducted in pediatric urology investigate the clinical results. However, very few studies explore the relationship between surgery and quality of life and psychosocial well-being in pediatric urology practice. Especially after surgery, It was observed that the studies evaluating the mental effects of the surgical method and the quality of life were essential. The current study investigated the psychological factors of child and parent, sociodemographic, medical and surgical factors that may affect the quality of life and psychological well-being of patients aged 4-18 years who were hospitalized and operated in the pediatric urology clinic. For this purpose, patients and parents were evaluated in the preoperative period and at the 7th month postoperatively. Before the surgery, a patient diagnosed with an active psychiatric disorder in the psychiatric interview using the Schedule for Affective Disorders and Schizophrenia for School Aged Children, Present and Lifetime Version ( K- SADS- PL) were excluded from the study. The study was conducted with 98 patients who met the inclusion criteria in the preoperative period and 63 patients in the postoperative period. Of all the parents included in the study to evaluate the psychiatric symptom areas two times, preoperatively and postoperatively; Pediatric Quality of Life Inventory- Parent report, Strengths and Difficulties Questionnaire- Parent report (SDQ); in relation to themselves Beck Anxiety Inventory, Beck Depression Inventory, Symptom Checklist (SCL-90-R), Orientation to Problems Experienced (COPE) inventory was requested to fill. Children and adolescents also filled in the Children's Depression Inventory (CDI), the Pediatric Quality of Life Inventory- self-report, and the State-Trait Anxiety Inventory for Children (STAI-CH). The surgeries of the patients evaluated within the scope of the study were examined in two different groups as open surgery/endourological surgery and major surgery/minor surgery. In the linear regression analysis, the variables that most predicted both the total score of quality of life reported by parents (p<0,001, adjusted R2: 0,304) and the total score of quality of life reported by children (p<0,001, adjusted R2: 0,304) after surgery were found to be parental SCL-90 total score, number of previous surgeries, and female gender. Preoperative depression scores and SCL-90 general symptom level scores of the minor surgery group's parents were significantly lower than those in the major surgery group (p: 0,023 and p: 0,010, respectively). In addition, the preoperative self-report quality of life physical score was higher in the minor surgery group (p: 0,036), while the post-surgical self-report quality of life total score increased statistically in this group (p: 0,037). Major surgery/minor surgery grouping was associated with both the child and parent's preoperative and postoperative mental well-being and the child's quality of life. However, the same significance was not seen in the open surgery/endourologic surgery grouping. This situation is clinically significant, and it was thought that factors related to the underlying preoperative psychological and medical disease rather than the type of surgical method affect the child and parents. In the future, following the forms of the surgical method in larger and homogeneous samples, with longer and more frequent psychosocial follow-ups, may shed light on surgeons when deciding on clinical applications in the future.Çocuk üroloji alanında yapılan çalışmaların büyük bir kısmı bu yöntemlerin klinik sonuçlarını değerlendirmektedir; yaşam kalitesi ve psikososyal iyilik hali ile cerrahinin ilişkisine dair çocuk üroloji pratiğinde çok az çalışma mevcuttur. Özellikle de cerrahi yöntemin şeklinin cerrahi sonrası ruhsal etkileri ile yaşam kalitesinin değerlendirildiği çalışmalara ihtiyaç olduğu gözlenmiştir. Bu araştırmada çocuk üroloji kliniğinde yatırılarak ameliyat edilen 4-18 yaş arası hastaların yaşam kalitesi ve psikolojik iyilik hali üzerine etkisi olabilecek; sosyodemografik, medikal, cerrahi ve ebeveyn ve çocuğa ait psikolojik faktörler araştırılmıştır. Bu amaçla hasta ve ebeveynler ameliyat öncesi dönemde ve ameliyat sonrası 7. ayda değerlendirilmiştir. Cerrahiden önce Okul Çağı Çocukları için Duygulanım Bozuklukları ve Şizofreni Görüşme Çizelgesi- Şimdi ve Yaşam Boyu Şekli (ÇDŞG-ŞY-T) kullanılarak yapılan psikiyatrik görüşmede aktif herhangi bir psikiyatrik bozukluk tanısı konan hastalar çalışma dışında bırakılmıştır. Ameliyat öncesi dönemde dahil edilme ölçütlerini karşılayan 98 hasta, ameliyat sonrası dönemde ise 63 hasta ile çalışma gerçekleştirilmiştir. Ameliyat öncesi ve sonrası 7. ay olmak üzere iki kez psikiyatrik belirti alanlarını değerlendirmek amacıyla çalışmaya dahil edilen tüm ebeveynlerden; Çocuklar için Yaşam Kalitesi Ölçeği-Ebeveyn formu (ÇİYKÖ), Güçler Güçlükler Anketi Ebeveyn Formu (GGA); kendileri ile ilgili olarak ise Beck Anksiyete Ölçeği, Beck Depresyon Ölçeği, Belirti Tarama Listesi’ni (SCL-90-R), Başa Çıkma Tutumlarını Değerlendirme Ölçeği’ni (COPE) doldurmaları istenmiştir. Çocuk ve ergenler de Çocuklar için Depresyon Ölçeği (ÇDÖ), Çocuklar için Yaşam Kalitesi Ölçeği, Çocuklar için Durumluk – Sürekli Kaygı Envanteri (ÇDKE – ÇSKE) doldurmuştur. Araştırma kapsamında değerlendirilen hastaların geçirdiği cerrahiler açık cerrahi/endoürolojik cerrahi ve majör cerrahi/minör cerrahi olarak iki farklı gruplandırma ile incelenmiştir. Yapılan doğrusal regresyon analizinde çocuklarda cerrahi sonrası hem ebeveynin bildirdiği yaşam kalitesi toplam puanını (p<0,001, düzeltilmiş R2: 0,304) hem de özbildirim yaşam kalitesi toplam puanını (p<0,001, düzeltilmiş R2 :0,304) en çok yordayan değişkenler ebeveyn SCL-90 Genel Şiddet skoru, geçirilmiş cerrahi sayısı ve kadın cinsiyet olarak bulunmuştur. Minör cerrahi grubundaki ebeveynlerin ameliyat öncesi depresyon puanları (p: 0,023) ve SCL- 90 genel belirti düzeyi puanları (p: 0,010), majör cerrahi grubundan anlamlı olarak düşük bulunmuştur. Ek olarak minör cerrahi grubunda cerrahi öncesi özbildirim fiziksel yaşam kalitesi puanı daha yüksek bulunurken (p: 0,036), bu grupta cerrahi sonrası özbildirim yaşam kalitesi toplam puanının istatistiksel olarak da arttığı (p: 0,037) görülmüştür. Majör cerrahi/minör cerrahi gruplandırmasının hem ameliyat öncesi hem de ameliyat sonrası hem çocuk hem de ebeveynin ruhsal iyilik hali ve çocuğun yaşam kalitesi ile ilişkili olduğu saptanmıştır. Ancak aynı anlamlılığın açık cerrahi/endoürolojik cerrahi gruplandırmasında görülmemesi, çocuk ve ebeveynleri cerrahi yöntemin şeklinden çok altta yatan ameliyat öncesi medikal ve psikolojik hastalıkla ilişkili faktörlerin etkilediği düşünülmektedir. Cerrahi yöntemin şekillerinin gelecekte daha büyük ve homojen örneklemlerde, daha uzun ve daha sık aralıklı psikososyal izlem ile takip edilmesi, ileride klinik uygulamalara karar verilirken cerrahlara ışık tutabilecektir

Impact of Varicocele Repair on Semen Parameters in Infertile Men: A Systematic Review and Meta-Analysis

Authors wish to thank the members of the Global AndrologyForum for their support.International audienceDespite the significant role of varicocele in the pathogenesis of male infertility, the impact of varicocele repair (VR) on conventional semen parameters remains controversial. Only a few systematic reviews and meta-analyses (SRMAs) have evaluated the impact of VR on sperm concentration, total motility, and progressive motility, mostly using a before-after analytic approach. No SRMA to date has evaluated the change in conventional semen parameters after VR compared to untreated controls. This study aimed to evaluate the effect of VR on conventional semen parameters in infertile patients with clinical varicocele compared to untreated controls.A literature search was performed using Scopus, PubMed, Embase, and Cochrane databases following the Population Intervention Comparison Outcome (PICOS) model (Population: infertile patients with clinical varicocele; Intervention: VR [any technique]; Comparison: infertile patients with clinical varicocele that were untreated; Outcome: sperm concentration, sperm total count, progressive sperm motility, total sperm motility, sperm morphology, and semen volume; Study type: randomized controlled trials and observational studies).A total of 1,632 abstracts were initially assessed for eligibility. Sixteen studies were finally included with a total of 2,420 infertile men with clinical varicocele (1,424 patients treated with VR vs. 996 untreated controls). The analysis showed significantly improved post-operative semen parameters in patients compared to controls with regards to sperm concentration (standardized mean difference [SMD] 1.739; 95% CI 1.129 to 2.349; p<0.001; I²=97.6%), total sperm count (SMD 1.894; 95% CI 0.566 to 3.222; p<0.05; I²=97.8%), progressive sperm motility (SMD 3.301; 95% CI 2.164 to 4.437; p<0.01; I²=98.5%), total sperm motility (SMD 0.887; 95% CI 0.036 to 1.738; p=0.04; I²=97.3%) and normal sperm morphology (SMD 1.673; 95% CI 0.876 to 2.470; p<0.05; I²=98.5%). All the outcomes showed a high inter-study heterogeneity, but the sensitivity analysis showed that no study was sensitive enough to change these results. Publication bias was present only in the analysis of the sperm concentration and progressive motility. No significant difference was found for the semen volume (SMD 0.313; 95% CI -0.242 to 0.868; I²=89.7%).This study provides a high level of evidence in favor of a positive effect of VR to improve conventional semen parameters in infertile men with clinical varicocele. To the best of our knowledge, this is the first SRMA to compare changes in conventional semen parameters after VR with changes in parameters of a control group over the same period. This is in contrast to other SRMAs which have compared semen parameters before and after VR, without reference to a control group. Our findings strengthen the available evidence and have a potential to upgrade professional societies' practice recommendations favoring VR to improve conventional semen parameters in infertile men